[Federal Register Volume 63, Number 210 (Friday, October 30, 1998)]
[Proposed Rules]
[Pages 58460-58521]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-28118]
[[Page 58459]]
_______________________________________________________________________
Part II
Department of Transportation
_______________________________________________________________________
Research and Special Programs Administration
_______________________________________________________________________
49 CFR Part 107, et al.
Hazardous Materials: Requirement for DOT Specification Cylinders;
Proposed Rule
Federal Register / Vol. 63, No. 210 / Friday, October 30, 1998 /
Proposed Rules
[[Page 58460]]
DEPARTMENT OF TRANSPORTATION
Research and Special Programs Administration
49 CFR Parts 107, 171, 172, 173, 177, 178, and 180
[Docket No. RSPA-98-3684(HM-220)]
RIN 2137-AA92
Hazardous Materials: Requirements for DOT Specification Cylinders
AGENCY: Research and Special Programs Administration (RSPA) DOT.
ACTION: Notice of proposed rulemaking (NPRM) and public meeting.
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SUMMARY: RSPA proposes to amend certain requirements in the Hazardous
Materials Regulations (HMR) to establish four new DOT cylinder
specifications and to revise the requirements for maintenance,
requalification, and repair of all DOT specification cylinders. In
addition, RSPA proposes to: revise the requirements for approval of
cylinder requalifiers, independent inspection agencies, and nondomestic
chemical analysis and tests; revise the cylinder requalification,
maintenance and repair requirements; and to revise the requirements for
hazardous materials that are authorized to be offered for
transportation in cylinders. Finally, this NPRM incorporates a proposal
to remove from use aluminum alloy 6351-T6 that was published in an
advance notice under Docket HM-176A and terminates that docket (RIN:
2131-AB51).
This action is being taken to--simplify the HMR for construction of
cylinders; provide for flexibility in the design, construction and use
of cylinders; recognize recent advances in cylinder manufacturing and
requalification technologies; promote safety though simplification of
the regulations; reduce the need for exemptions; and facilitate
international commerce. The intended effect of this action is to
enhance the safe transportation of hazardous materials in cylinders.
DATES: Comment Date: Comments must be received on or before January 28,
1999.
Public Meeting Date: A public meeting will be held on December 8,
1998; from 9:30 am to 4:00 pm. An additional meeting may be scheduled
if there is substantial interest.
ADDRESSES: Written Comments: Address comments to the Dockets Management
System, U.S. Department of Transportation, PL 401, 400 Seventh St., SW,
Washington, DC 20590-0001. Comments should identify the docket number,
RSPA 98-3684(HM-220), and should be submitted in two copies. Persons
wishing to receive confirmation of receipt of their comments should
include a self-addressed stamped postcard. The Dockets Management
System is located on the Plaza Level of the Nassif Building, at the
above address.
Public dockets may be reviewed between the hours of 10:00 a.m. to
5:00 p.m., Monday thru Friday, excluding Federal holidays. In addition,
comments can be reviewed by accessing the DOT Homepage (http://
www.dot.gov). Comments may also be submitted by E-mail to
``[email protected]''. In every case, the comment should refer to the
Docket number set forth above.
Public Meeting: The public meeting will be held in Room 3200-3204
at the U.S. Department of Transportation's Nassif Building, 400 7th
Street SW, Washington DC, 20590.
FOR FURTHER INFORMATION CONTACT: Cheryl Freeman, telephone number (202)
366-4545, Office of Hazardous Materials Technology, or Ryan Posten,
telephone number (202) 366-8553, Office of Hazardous Materials
Standards, Research and Special Programs Administration, U.S.
Department of Transportation, Washington, DC 20590-0001.
SUPPLEMENTARY INFORMATION:
I. Background
Federal hazardous material transportation law (Federal hazmat law),
49 U.S.C. 5101-5127, authorizes the Secretary of Transportation to
regulate the manufacture and continuing qualification of packagings
used to transport hazardous materials in commerce, or packagings
certified under Federal hazmat law for the transportation of hazardous
materials in commerce. The HMR, 49 CFR parts 171-180, contain
requirements for the manufacture, use, and requalification of cylinders
subject to Federal hazmat law, including defining materials and methods
of construction, the frequency and manner of inspection and testing,
standards for cylinder rejection and condemnation, cylinder marking and
recordkeeping, authorizations for packaging hazardous materials in
cylinders, filling, loading, unloading, and carriage in transportation.
Historically, Federal authority to regulate the transportation of
compressed gases was given to the former Interstate Commerce Commission
(ICC) through the Transportation of Explosives Act, 35 Stat. 1135,
section 233 (March 4, 1909), which was later amended in 1921, at 41
Stat. 1445, Sec. 233. In 1911 the ICC adopted a series of ``Shipping
Container Specifications,'' among which the ICC 3 specification for
seamless steel cylinders was codified. That same year, the ICC 4
specification for a lap-welded cylinder for anhydrous ammonia was also
published. As the welding process improved, from the riveted/brazed
welds to resistance welding and then butt welding by the metal-arc
process, the ICC 4 Specification series was expanded to include the
4BA, the 4BW, and others. By 1914, two other cylinder specifications
were codified: the ICC 7 specification for steel cylinders for low
pressure, nonliquefied gas, (which have carried over to the present
regulations, but not as specification 7) and the ICC 8 specification
for acetylene gas cylinders, which still exists today with minor
changes.
In 1930, the ICC implemented regulations for periodic inspection
and testing of cylinders; the regulations, as amended, were first
published in the Federal Register on December 12, 1940 (5 FR 4908).
During the 1930's and 1940's, the Compressed Gas Association (CGA)
developed and refined the water jacket test method for determining the
serviceability of a cylinder. During World War II, there was a shortage
of high pressure gas cylinders. Because of CGA's work on steel wall
stress limitations, the ICC granted ``temporary'' regulatory relief to
increase the gas carrying capacity of existing cylinders by allowing
the cylinders to be filled 10% over their marked service pressures, and
by marking those cylinders with a plus, ``+'', mark. Ten years later,
the regulations were codified into the Code of Federal Regulations (15
FR 8261; Dec. 2, 1950). In 1967, pursuant to the Department of
Transportation Act, Pub. L. 89-670, 80 Stat. 931, regulatory
responsibility for the transportation of dangerous articles in commerce
was transferred from the ICC to DOT.
Through rulemaking and the issuance of exemptions from the
regulations under 49 CFR part 107, subpart B, materials other than
steel (e.g., aluminum and composite cylinders) now are authorized for
use. Nevertheless, apart from the substitution of the ``DOT''
identifier for the ``ICC'' identifier, many of today's basic
requirements remain virtually unchanged from the time they were first
incorporated into the regulations.
Over the years, RSPA has received numerous petitions for rulemaking
requesting various changes to the cylinder requirements. CGA filed most
of these petitions that request changes to
[[Page 58461]]
the cylinder specifications. In 1969, CGA submitted a petition (P-69)
containing six new proposals and revising eight previously-filed
petitions. Many of these 14 petitions were handled in subsequent
rulemakings such as Docket HM-69 adding a DOT 39 non-reusable, non-
refillable specification cylinder (August 24, 1971; 36 FR 16579),
Docket HM-85 updating the DOT-4L cylinder material properties (Nov. 5,
1971; 36 FR 21287), and Docket HM-99 adding the DOT-3T specification
cylinder (Aug. 15, 1973; 38 FR 21989).
In 1981, RSPA adopted a DOT 3AL specification under Docket HM-176
(46 FR 62452). This new specification for a seamless aluminum cylinder,
made of definitely prescribed alloys, was based in part on the
petitions received from industry and an agency initiative to
consolidate and eliminate the need for seven exemptions authorizing the
manufacture of seamless aluminum cylinders. In 1984, CGA petitioned (P-
953) to include a welded stainless steel cylinder similar to the DOT-
4BW. At that time, CGA proposed the designation ``4SS'' for the new
stainless steel cylinder.
In 1990, CGA petitioned to add a new 3F specification for a
seamless steel compressed gas cylinder designed for a high stress level
similar to the DOT-3T, but with a stronger structural integrity similar
to the DOT-3AA cylinder. The proposed 3FM specification provides for a
greater efficiency in gas transportation.
The above-mentioned petitions were given full consideration in the
development of this NPRM. In developing this NPRM, RSPA worked closely
with the cylinder manufacturing and maintenance industries, and held
several meetings with CGA to obtain clarification of the CGA petitions.
RSPA also held public outreach meetings with industry that were
announced in the Federal Register. The industry proposals and petitions
have been refined by RSPA based on RSPA's compliance inspections and
exemption program, interpretations issued by RSPA, and certain industry
consensus standards and practices that have proven to be safe. RSPA
believes the proposals in this NPRM are consistent with sound industry
practice and incorporate modern manufacture and requalification
technology.
Some of the more significant proposals contained in this NPRM are:
1. The establishment of four new cylinder specifications that are
more performance-oriented and the removal of several obsolete
specifications. These proposed specifications are expressed in metric
units, require marking of the cylinder with test pressure in place of
service pressure, and are distinguishable by their specification
designation markings.
2. The new specifications allows greater flexibility in the design
and construction of metric-marked cylinders.
3. Independent inspection of all metric-marked cylinders, both
seamless and welded.
4. Design qualification testing of metric-marked cylinders.
5. The requalification of metric-marked cylinders and certain
nonmetric-marked cylinders using thickness and shear wave ultrasonic
testing in place of the volumetric pressure test.
6. Requiring any person who performs a requalification function
that requires marking an inspection or retest date on the cylinder to
have approval from the Associate Administrator for Hazardous Materials
Safety (herein after referred to as the Associate Administrator).
7. Standardizing the requirements for the repair and rebuilding of
DOT 4 series cylinders, other than the DOT 4L.
8. Allowing a 10-year interval for requalification of DOT 3-series
metric-marked cylinders used in certain types of service.
9. Allowing a 15-year interval for requalification of certain DOT
4-series metric-marked cylinders used in certain types of service.
10. Allowing, upon approval by the Associate Administrator, the
application of requalification markings on cylinders by using
alternative methods that produce durable legible marks.
11. Implementing valve damage protection and puncture resistance
criteria for all DOT specification cylinders used for Division 2.3 or
6.1 materials in Hazard Zone B, and puncture resistance criteria for
those in Hazard Zone A.
12. Discontinuing authorization for a filled cylinder with a
specified service life from being offered for transportation in
commerce after its service life has expired.
13. Providing filling pressures for metric-marked cylinders based
on critical temperature, test pressure, and draft ISO Standard 11622.
14. Requiring that pressure relief devices on all metric-marked
specification cylinders be set at no less than test pressure. Requiring
that pressure relief devices on all 3-series, nonmetric-marked
specification cylinders be set at no less than test pressure from the
first requalification due after the effective date of the final rule.
II. New specification Standards for Metric-marked Cylinders
A. Consolidation of Cylinder Standards
As discussed above, the current cylinder requirements have their
origin in the early 1900's. The regulations were developed in a
piecemeal fashion, with adjustments being made to address particular
situations and problems on a case-by-case basis. This NPRM represents
RSPA's first comprehensive review of the cylinder requirements.
RSPA proposes to establish four new cylinder specifications for
seamless and welded cylinders. These proposed cylinder specifications
are more performance oriented and incorporate provisions that recognize
certain domestic and international practices. Cylinders made to these
specifications would be marked in metric units and would be
distinguished by a unique specification marking that closely
approximates the markings in draft International Standards Organization
(ISO) and the European Committee for Standardization (CEN), Technical
Committee, entitled ISO/TC58/SC4 ``Gas Cylinders Operational
Requirements,'' based on CEN Standard EN 1089-1, ``Transportable gas
cylinders--Gas cylinder identification--Part 1: Stampmarking.''
The new seamless cylinder specifications are identified as DOT 3M,
3ALM, and 3FM. The welded cylinder specification is identified as the
DOT 4M. Eventually, RSPA anticipates that the DOT 3M specification will
replace the current DOT 3A, 3AA, 3AX, 3AAX, 3B, and 3BN specifications.
The DOT 3ALM specification will replace the 3AL specifications. The DOT
3FM will replace the higher strength 3AA and the 3T specifications. The
DOT 4M will replace the 4B, 4BA, 4BW, 4B240X, 4B240ET, and 4E. In
future rulemakings, RSPA plans to propose new metric-marked cylinder
specifications to replace the current specifications for the DOT 3E,
3HT, 4D, 4DA and 4DS; the 4L; the 8 and 8AL; and the DOT 39.
The basic specification requirements, those common to most metric-
marked cylinders, are in proposed Sec. 178.69. This section contains
definitions, material of construction, duties of the inspector, and
criteria for all design and production qualification tests that may be
required by the individual specifications. Proposed Sec. 178.70
contains requirements applicable to seamless cylinders. The individual
specifications, containing additional requirements, are in Sec. 178.71
for the DOT 3M, Sec. 178.72 for the DOT 3ALM, and Sec. 178.73 for the
DOT 3FM. Proposed Sec. 178.81 contains
[[Page 58462]]
requirements applicable to DOT 4M welded cylinders.
In all cases where the new proposed specifications differ, the new
specification requirements will have a level of integrity that is
equivalent to, or greater than, the current nonmetric specification
requirements. Significant changes from current requirements are
discussed further in this preamble.
B. Cylinder Filling Limits
CGA petitioned RSPA to change the test pressure from 5/3 times
service pressure for currently authorized DOT specification seamless
cylinders to 3/2 times service pressure for newly constructed DOT
specification seamless cylinders. In effect, the CGA proposal would
increase the filling limit for most of the new seamless DOT
specification cylinders to that currently authorized for cylinders
marked with a ``+'' sign (see 49 CFR 173.302(c)). In the historical and
technical information provided to support its petition, CGA stated:
I. Background
In 1942 during the height of industrial production for WWII, a
shortage of high pressure gas cylinders developed. The shortage was
hampering the War effort. The three manufacturers of large size
cylinders were also forging shells and bombs and did not have
capacity to forge those and the required quantities of high pressure
steel cylinders.
The War Production Board brought this concern to the Compressed
Gas Association (CGA) to seek a remedy for the shortage of high
pressure cylinders. One idea was to start up new production by
spinning seamless tubing, which was initiated by Cueno-Press and
Taylor Forge; but that would take months. An immediate ``temporary''
relief was conceived which was to increase gas carrying capacity by
allowing an ``overfill'' of existing cylinders. After careful study,
the increase of 10% in filling pressure (i.e., from 2015 to 2215
psi) was considered safe and technically sound because of the
conservative design required by DOT Specification 3A and of the
existing high pressure cylinders produced thereto.
For example: A 10% increase in wall stress at the increased
filling pressure maintained the operating stress well below the
yield point of the steel; and so, cyclic fatigue failure would not
become a factor for the ductile, low strength steel. Furthermore,
the operating stress would still be far below the ultimate tensile
strength providing an adequate safety factor which related service
pressure to rupture pressure; and the only way the cylinder pressure
of permanent gases could reach burst pressure was by involvement in
a fire.
By joint agreement between the War Production Board, Interstate
Commerce Commission (ICC) and the Gas Industry, it was decided to
immediately allow a ``10% overfill'' for the existing cylinder
fleet. This was to be allowed for both flammable and non-flammable
permanent gases.
To make this effective required a change in the ``Regulations''
covering ``Charging of Cylinders with Non-liquefied Compressed
Gases'' because it was to be applied to existing cylinders as well
as new production. Therefore, section 173.302 was changed and 178
was not changed to cover cylinder design and production. Thus, a 10%
increase in the gas carrying capacity of the existing cylinder fleet
and new current production was immediately achieved. This had the
effect of adding 10% additional cylinders.
II. Technical Rationale for Allowing 10% Higher Fill Pressures
A. Introduction
The fleet of DOT 3 Series cylinders in use during the war years
performed safely without a service failure, notably from fatigue or
gas pressure rupture. Thus, the carefully considered decision to
allow the charging pressure to be increased by 10% was considered to
be proven safe and technically valid.
The compressed gas industry monitored performance of their
cylinder fleets and concluded that the ``temporary'' over-filling
procedure could safely become a permanent regulation. However, CGA
decided to recommend certain controls to justify permanent
continuation of this change which effected the design safety factor.
Those controls are now contained in CFR Title 49, clause 173.302 (c)
entitled ``Special filling limits for Specification 3A, 3AA, 3AX,
3AAX and 3T cylinders''.
The technical rationale for those controls was: * * *
(1) ``That such cylinders are equipped with frangible disc
safety relief devices (without fusible metal backing) having a
bursting pressure not exceeding the minimum prescribed test
pressure.''
Rationale: This was to guarantee that cylinder pressure from any
source could never reach the cylinder design burst pressure.
Therefore, lowering the ratio of service pressure to rupture
pressure, was meaningless because the cylinders would be equipped
with a ``rupture port'' which would vent the gas pressure at a pre-
determined pressure and prevent the cylinder from ever reaching its
``burst'' pressure. * * *
(2) ``That the elastic expansion shall have been determined at
the time of the last test or retest by the water jacket method.''
Rationale: In the 1930s and 1940s the CGA had developed and
refined the water jacket test method, and developed the mathematical
relationship of wall stresses as measured by the elastic expansion
of individual cylinder designs. The average wall stress as
determined by elastic expansion measured by the water jacket
hydrostatic test was limited to a specified stress less than the
permitted maximum design stress. For example, 3AA design cylinders
were to be rejected if the elastic expansion exceeded a value
equivalent to the strain developed at an average wall stress of
67,000 psi; whereas, the design wall stress limit in 178.37-10(b) is
70,000 psi. This 4% decrease in wall stress was selected because
elastic expansion measures the average effective wall thickness and
not the minimum. At the same time it was concluded that a small
increase (i.e., 4%) in the stress at isolated areas of a cylinder
could be safely tolerated to allow for localized damage or thinning;
and a ``Maximum wall stress limitation'' was set; e.g., 73,000 psi
for 3AA design cylinders. This procedure of elastic expansion
control was developed to further justify the permanent use of the
``10% overfill'' by guaranteeing that such cylinders would be
controlled by limiting the loss of wall thickness so that the stress
at service pressure would be below the yield point of the cylinder
steel. * * *
(3) ``That either the average wall stress or the maximum wall
stress shall not exceed the wall stress limitations shown in the
following table.''
Rationale: Wall stress limitations for both average wall and
isolated spots were developed for each ``class of steel'' used for
ICC 3, DOT 3A, and DOT 3AA cylinder designs. (Much later DOT-3T was
added.) These limits were selected from known physical properties of
these steel classes; and were set to assure that stress at operation
pressures were: (1) well below yield point and (2) that an adequate
burst pressure to service pressure ratio was obtained. This clause
amplifies the preceding clause 2.
(4) ``That an external and internal visual examination made the
time of test or retest shows the cylinder to be free from excessive
corrosion, pitting, or dangerous defects.''
Rationale: The body of data and service experience available
within the CGA had proven that the design criterion for DOT high
pressure cylinders was eminently safe; especially as regards cycle
life and rupture in service. The only cause of cyclic or tensile
rupture would be damage inflicted during manufacture or service.
Thus, the visual inspection before and during use was considered to
be an essential safety measure, which continues to be true today.
(5) ``That a plus sign (+) be added following the test date
marking on the cylinder to indicate compliance with paragraphs (c)
(2), (3) and (4) of this section.''
Rationale: This was to force both the cylinder manufacturer and
user to take a physical act to signify their guarantee of compliance
with the control methods. This also was an easily discerned mark
that permitted personnel to identify which cylinders were
satisfactory, safe and qualified for charging to the ``10%
overfill''.
B. Wall Stress and Safety Factors of Series 3 DOT Cylinders
The most common high pressure cylinder in use in 1942 was the
ICC-3A-2015 with size of 9'' O.D. x 51'' long, rated at 220 cubic
feet oxygen capacity. This cylinder made of normalized intermediate
manganese steel had an ultimate tensile strength of about 95,000 psi
and had excellent ductility and good charpy impact strength at
-50 deg.F. to assure safe fracture performance. The design stress at
test pressure was 49,500 psi which with the 5/3 test pressure ratio
allows a stress of 29,600 psi at 2015 psi service pressure. The
yield point was about 69,000 psi (about 0.73 x U.T.S.). Thus the
service stress was about 50% of yield stress, which level assured a
long (virtually infinite) cycle life. The burst stress to service
stress ratio (safety factor) was about 3.2 (95,000
29,600).* * *
[[Page 58463]]
This ratio of operating stress compared to ultimate strength was
obviously a conservative design. The conservatism is more obvious in
view of the fact that the cylinders were seamless, forged, high
quality steel pressure vessels which have no stress concentration
points in the longitudinal plane of major stress. Furthermore, they
were used in non-corrosive gas service and have no source to
increase the contained pressure during use except by the small
fluctuations in ambient temperature or a fire. The cylinders are
also subjected to periodic requalification. In view of these facts/
data and the excellent service record, the decision was made in 1942
to allow stress to increase about 32,600 psi at service pressure for
the ``10% overfill''. This equates to a working stress to burst
strength ratio of 2.9 (95,000 32,600).
Thus the ``10% overfill'' was considered technically appropriate
and eminently safe as a way to increase the oxygen carrying capacity
from 220 CF to 244 CF. These cylinders have continued in service for
over 50 years with a perfect safety record as regards cyclic or
pressure rupture in service. The same effective stress at test
pressure can be achieved by testing either at 5/3 of 2015 or 3/2 of
2215. These pressures are 3358 and 3323 which stresses the wall to
49,350 and 48,720 psi respectively. This 1.2% difference in test
pressure stress would be inconsequential with respect to cylinder
safety. Therefore, the test pressure in the DOT 3A, 3AA, and 3T
specifications can safely be changed to 3/2 instead of 5/3 service
pressure. The following paragraph describes graphic presentation of
the situation with intermediate manganese normalized and chrome-moly
quenched and tempered, which represents virtually 100% of the 3A and
3AA cylinders in the U.S. * * *
It is proposed to write all the ``10% overfill'' into the design
conditions for DOT 3A, 3AX, 3AA, 3AAX, 3F (new) and 3T. This can be
accomplished by merely changing the required test pressure from 5/3
x service pressure to 3/2 x service pressure. For all intents and
purposes, the cylinders would be exactly the same as discussed
above. * * *
III. Conclusions
1. DOT 3A and 3AA cylinders have been in use since 1942 (54
years) with a ratio of test pressure to service pressure of 3/2. At
time of manufacture or retest, the cylinders are tested at 5/3 x
service pressure; but the service pressure is increased by 10% for
filling.
2. The 10% overfill pressure times 3/2 results in a wall stress
at test pressure only 1% less than the requirement to test at 5/3
times marked service pressure.
3. The 3/2 test pressure would result in a calculated minimum
wall of barely 0.001 inch less for a current cylinder with a 0.250
wall minimum.
4. The tiny decrease in wall thickness and effect of 1% lower
stress at test pressure would have no effect in overall cylinder
safety.
5. The service record since 1942 (54 years) has been perfect as
regards rupture under gas pressure and cyclic fatigue
characteristic. The change to 3/2 test versus 5/3 does not change
any measurable characteristic which would effect these failure
modes.
6. The ASME Code uses a 3/2 test pressure to working pressure
ratio.
7. Europe (18 countries) uses the 3/2 test to service pressure
ratio.
IV. Recommendation
The minimum prescribed test pressure shall be 3/2 times the
marked service pressure for all cylinders with a marked service of
500 psi or greater for all Series 3 steel cylinders. This should
also be considered for cylinders made of nickel, aluminum or
stainless steel.
In considering the issue of cylinder filling limits, RSPA also
reviewed technical information supplied by cylinder manufacturers and
by holders of exemptions that authorize either a test pressure of 3/2
times service pressure or 10% overfill for materials not currently
specified in 49 CFR 173.302(c), the hazardous materials information
system data base for incidents involving ``+'' marked cylinders, and
the work currently being done by the ISO and the United Nations Group
of Experts on the Transport of Dangerous Goods. After reviewing all the
available information, RSPA has concluded that from a transportation
safety perspective, there is no technical reason or safety experience
which would prohibit increasing the cylinder filling limits for
seamless cylinders to those comparable to the levels currently
authorized in 49 CFR 173.302(c). Therefore, RSPA has accepted the CGA
proposal to increase the filling limits for new cylinders, in
principle, but has chosen to limit the proposal for increased filling
limits to metric-marked DOT Specification cylinders. Additionally, RSPA
has not changed the requirements in 49 CFR 173.302(c) for the current
DOT specification cylinders, but has moved them to proposed
Sec. 173.302a(b).
With regards to existing cylinders, RSPA is considering a process
for accepting certain DOT specification cylinders as meeting the new
metric specifications, but is still considering various conversion
criteria. RSPA solicits comments from interested persons as to the
interest and feasibility of developing such a conversion program and,
if feasible, specific criteria for requalifying and conversion of
existing cylinders.
C. Specification Markings on Metric-marked Cylinders
In the CGA submission to RSPA, it was requested that cylinders be
marked in bar rather than psig. Bar is an internationally accepted
metric unit for pressure in the compressed gas industry. This change
would help make marking DOT specification cylinders consistent with the
practice in most European countries which are currently marking
cylinders with the test pressure shown in bar.
While considering this request, RSPA reviewed its current marking
requirements as well as two draft documents on the subject of cylinder
marking being considered by the ISO and the CEN. The documents are ISO/
DIS 13769, ``Gas cylinders--Stamp marking,'' and CEN Standard EN 1089-
1, ``Transportable gas cylinders--Gas cylinder identification--Part 1:
Stampmarking.''
Based upon this review, RSPA proposes to change the way DOT
specification cylinders are marked. The new marking scheme will change
the number and sequence of marks required to be placed on DOT
specification cylinders by manufacturers and is consistent with the
sequence being proposed by both ISO and CEN. However, RSPA does not
proposed to require all of the cylinder marks contained in either the
ISO or CEN documents. The proposed marking scheme will also make it
easier to identify those cylinders manufactured to the proposed
specifications. Additionally, the marking scheme is similar to the type
of marking scheme contained in the United Nations Recommendations for
the Transport of Dangerous Good for non-bulk packagings and
intermediate bulk containers.
The proposed marking sequence, with each element separated by a
slash mark, is as follows:
DOT Specification
Country of origin
Manufacturer's identification
Serial number
Stamp for non-destructive testing (if applicable)
Minimum wall thickness
Water capacity (liters)
Test pressure (bar)
Identification of alloy
Tare weight (kg)
Identification of inspection agency
Test date
REE (if applicable)
The most significant change is the marking of the new specification
cylinders with test pressure instead of service pressure. DOT
specification cylinders have always been designed to test pressure
rather than service pressure. Specifically, the stress formulas used to
determine the minimum wall thickness of DOT specification cylinders are
calculated at the minimum test pressure.
[[Page 58464]]
Additionally, as currently authorized in 49 CFR 173.302(c), many
cylinders used to transport compressed gases which are not liquefied,
dissolved, toxic or flammable are filled to a pressure 10% in excess of
their marked service pressure and 49 CFR 173.304(f) specifies, with
limited exceptions, that the pressure in the container at 130 deg.F
shall not exceed 5/4 times the marked service pressure. While marking
the test pressure rather than the service pressure will require the
training of persons who fill cylinders, it should not have any adverse
safety effects since inadvertently filling a cylinder to the marked
test pressure, in bar, would result in the cylinder being filled to a
lower pressure than the currently marked service pressure in psig.
Further, most cylinders are filled by a person who uses a filling table
that shows the values already adjusted for changes in temperature and
elevation. RSPA envisions that cylinders marked with test pressure will
also be filled by using filling tables.
III. Independent Inspection--New DOT Specification Cylinders
A DOT specification cylinder is, and has been for the past sixty
years, a widely recognized standard for the safe transportation of
compressed gases. This wide acceptance has resulted in significant
economic benefit to domestic industry far beyond the value of the
cylinders sold internationally. Market demand for gases and equipment
has increased as a direct result of the reputation of the DOT cylinder
for strength, durability and quality.
Since the early 1900's, cylinders manufactured under DOT's ``high
pressure'' specifications have required independent inspection,
originally referred to as ``disinterested inspection.'' Occasionally,
RSPA receives complaints from companies about costs of independent
inspection or claims that the companies' employees are as knowledgeable
and qualified, if not more so, as the independent inspector. However,
RSPA's Office of Hazardous Materials Enforcement, through its
compliance inspection program, has found a higher level of compliance
with the regulations when inspection and certification functions are
carried out by an Independent Inspection Agency (IIA) instead of by an
employee of the manufacturing company. In order for DOT specification
cylinders to be acceptable for service in most foreign countries,
cylinders must be certified through an inspection process which is not
controlled by the cylinder manufacturer. Since 1977, all DOT
specification cylinders manufactured outside the United States under
the RSPA foreign cylinder approvals program are required to be
inspected and certified by an IIA.
In order to maintain the high level of safety established over the
past 100 years, to maintain the acceptability of DOT specification
cylinders worldwide, and to facilitate the harmonization between
domestic and foreign cylinder specifications, RSPA is proposing that
all cylinders manufactured or rebuilt to the new DOT metric-marked
cylinder specifications be subject to inspection by an IIA. In effect,
this would continue the current DOT inspection requirements for
seamless cylinders and extend the practice to welded cylinders.
IV. DOT Approval of Cylinder Requalifiers
RSPA proposes that any person who requalifies a DOT specification
cylinder must be approved by the Associate Administrator prior to
performing any requalification function that requires an inspection or
retest date to be marked on the cylinder. The affected functions
include performance of a visual inspection, pressure test, ultrasonic
thickness test, repair, or the rebuilding of cylinders. This proposal
will enhance the accountability of the cylinder requalification
process.
Currently, Sec. 173.34(e)(13) permits a cylinder used exclusively
for certain liquefied gases to be requalified for use by performing an
external visual inspection and marking the cylinder with the test date
and an ``E''. The ``E'' indicates that the cylinder was requalified by
external visual inspection in accordance with CGA Pamphlet C-6 rather
than by a hydrostatic test. A person who performs only external visual
inspections is not required to obtain an approval from, or register
with, the Associate Administrator. Although current Sec. 173.34(e)(13)
requires these persons to maintain records, RSPA does not know who or
how many persons requalify and mark cylinders with an inspection date
and an ``E'', or the locations of their places of business. Also, RSPA
does not know whether these persons have the knowledge and skills
necessary to perform the required functions, including use of required
inspection standards.
RSPA inspectors have frequently observed DOT specification
cylinders, primarily in liquefied petroleum gas service, that bear
markings representing that they were requalified for use. The markings
reflected dates of recent requalification by external visual
inspection. One cylinder, marked with the letter ``E'' and the date ``6
98,'' was examined by RSPA personnel on June 19, 1998, and found to be
rusted to an extent that there is no doubt that the rust formed long
before the marked inspection date. Considering the amount of
undisturbed rust on the cylinder, it was apparent that the person
requalifying the cylinder did not properly prepare it for inspection by
first completely removing all rust from the exterior surface of the
cylinder, as required by paragraph 3.1 of CGA Pamphlet C-6, which was
developed by the compressed gas industry for adoption by reference as
Federal regulations.
In reviewing the approach for resolving this issue, RSPA considered
five options:
(1) Continue the current provision that allows persons who are not
known to RSPA to requalify cylinders by performing visual inspections;
(2) Adopt a registration program that would require persons who
perform visual requalification to be registered with RSPA and to mark
their requalifier identification numbers (RIN) on the cylinders they
inspect;
(3) Adopt an approvals program requiring that persons performing
requalifications of cylinders by visual inspection be approved by RSPA
upon written application containing statements regarding their
qualifications;
(4) Adopt an approvals program that would require persons
performing visual requalifications to be reviewed by an independent
inspection agency; and
(5) Discontinue visual requalification of cylinders, thereby
requiring all affected cylinders to be hydrostatically retested.
RSPA selected option 3 for this NPRM because it will not impose the
burden and added cost of employing an independent inspection agency
while ensuring the accountability of a person performing visual
requalifications and providing RSPA the authority to revoke or suspend
the person's approval for demonstrated non-compliance with the
requalification requirements. Also, by requiring a certification that
an applicant has the ability to perform requalifications, RSPA believes
each applicant's awareness of the importance of compliance will be
heightened. RSPA solicits comments on these options and others that
RSPA may not have considered.
V. Requalification Markings
RSPA proposes to amend Sec. 171.2(d) to prohibit the
misrepresentation of a requalification identification number (RIN)
marking. Over the years, through its compliance program, RSPA has been
[[Page 58465]]
in contact with dozens of individuals who did not perform the required
hydrostatic tests, but stamped the cylinders as though each cylinder
had passed the inspections and tests. The steel stamps used to mark the
cylinders are readily available, low-cost and simple to use. RSPA
believes that these and other factors (e.g., the high cost of
purchasing and maintaining hydrostatic test equipment when compared to
the mere cost of obtaining a set of steel stamps) provide an economic
inducement for some individuals to engage in fraudulent activities.
Based on recent enforcement data, this safety problem appears to be
more widespread than RSPA originally thought. RSPA is concerned about
the number of cylinders that are fraudulently stamped and then are used
to transport hazardous materials in commerce. These cylinders, whose
structural integrity has not been verified, pose substantial risks to
health, safety and property. When RSPA discovers these situations, RSPA
publishes a safety alert notice (see Notice No. 97-2, 62 FR 19651;
Notice No. 97-3, 62 FR 24548) and, where appropriate, refers the matter
to the Department of Justice for possible criminal prosecution (see
United States v. American Oxygen Company, et al., Docket No. 97-533
(D.N.M.)).
RSPA is also soliciting comments on the issue of what future method
or methods should be used to mark DOT specification cylinders during
the requalification process. Currently, after a cylinder meets the
requalification standards (e.g., passes a hydrostatic test, internal
and external visual examinations, etc.), the requalifier stamps the
month and year of the test and its RIN on the cylinder. This marking is
normally accomplished with steel stamps (Note: currently under an
exemption certain fiber-wrapped cylinders may be marked with labels.).
Through this rulemaking, RSPA is evaluating the merits of new marking
methods for DOT specification cylinders following the requalification
process.
RSPA is considering incorporating a number of marking options
(e.g., labeling, marking with a laser, replacing the RIN with a symbol
that is difficult to duplicate, etc.). RSPA is requesting comments from
the public as to the feasibility, costs and benefits of alternatives to
the metal stamping method and whether the public believes there is
justification for RSPA adopting an alternative method.
VI. Toxic Gases
Division 2.3 and 6.1, Hazard Zone A and B toxic inhalation hazard
(TIH) materials present a substantial risk to the public, transport
workers and emergency responders even when small quantities are
released. For smaller cylinders, shifting freight and dropping are
major sources of package damage and releases of hazardous materials.
Cylinders are sometimes dropped in handling, resulting in valve damage
or cylinder punctures. In a study of Hazardous Materials Information
System (HMIS) reports for the past 10 years, RSPA found that over 30%
of all reported cylinder incidents involved valve damage. Valve damage
occurs when valves are inadequately protected by outer packagings or
valve protection devices. Punctures most commonly occur when a cylinder
is impacted by handling equipment or other cargo or is dropped upon
other cargo or handling equipment. To reduce the probability that a
handling incident may result in the release of a TIH material, RSPA
proposes to expand the current drop test requirement for cylinders
containing TIH materials to include Hazard Zone B materials and a
performance test for cylinder puncture for TIH materials in Hazard
Zones A and B. These proposed performance tests apply to bare cylinders
and cylinders packed in strong outside packagings.
The performance test for puncture is based upon dropping a cylinder
seven feet; the same height used in the drop test for cylinder valve
protection. The seven-foot drop height represents the typical distance
that an industrial gas cylinder would encounter if it fell from a
truck. RSPA chose an angle iron (2 inch by 2 inch by 0.25 inch thick)
as a typical penetrator. The major parameters controlling cylinder
penetration are cylinder material, wall thickness, drop height and the
cylinder's gross weight. For consistency, RSPA proposes the cylinder
weight be the water-filled weight. To represent in-service stress
conditions, the proposed test is performed on the filled cylinder
charged to service pressure for nonmetric-marked cylinders and 67% of
test pressure for metric-marked cylinders.
The puncture-performance test would be required for metric-marked
and nonmetric-marked cylinders. To facilitate implementation of this
requirement for nonmetric-marked cylinders, RSPA is proposing a two-
year implementation period. RSPA also proposes a table showing
threshold values of wall thickness for cylinders of a particular
specification, material, and water-filled weight range. Cylinders
meeting the specified criteria with a minimum side wall thickness equal
to or greater than the value specified in the table would qualify under
current Sec. 173.40(d)(1) without puncture testing. To minimize the
testing burden, RSPA plans to perform puncture testing to develop
initial values for the table. RSPA is requesting that cylinder
manufacturers and shippers assist RSPA in developing this table. RSPA
is also soliciting comments on whether welded cylinders and cylinders
with wall thickness of 2.0 mm or less are used for the transportation
of Division 2.3 and 6.1 Hazard Zone B, C, and D materials. RSPA will
use this information to further develop the puncture testing threshold
table. When sufficient data is available, RSPA would consider the
development of a graph or calculation as a more practical means to
depict a minimum thickness threshold for puncture resistance.
VII. Discontinuation of Certain Cylinder Specifications
RSPA proposes to discontinue the use of the following DOT cylinder
specifications: 3C, 3D, 4, 4A, 4B240X, 4B240FLW, 4C, 9, 25, 26, 33, 38,
40 and 41. RSPA believes that these cylinders are obsolete and no
longer in general use. Authorization to manufacture these cylinders was
removed from the regulations on September 11, 1980 (45 FR 59887).
Comments are solicited from persons who may be using these cylinders.
If the proposals contained in this NPRM lead to publication of a
final rule, RSPA proposes to provide a transition period of five years
from the effective date of the final rule for the continued
construction of cylinders made to the following DOT specifications: 3A,
3AX, 3AA, 3AAX, 3AL, 3B, 3T, 3BN, 4B, 4BA, 4BW, 4B240ET, and 4E. RSPA
believes a five-year transition period for new construction of
cylinders conforming to these specifications will reduce the burdens
incurred by persons affected by this proposal. Cylinders made to these
specifications would be authorized for continued use as long as they
meet standards for periodic requalification. Voluntary compliance with
the new metric or revised requirements would be authorized 90 days
following publication of the final rule in the Federal Register.
VIII. Pressure Relief Device (PRD) Systems
In a previous rulemaking (see, Docket No. HM-220A, 61 FR 26750,
26756; May 28, 1996), RSPA proposed voluntary compliance with CGA
Pamphlet S-1.1, paragraph 9.1.1.1, which would require verification
that the PRDs operate properly. RSPA made this proposal based on the
view that
[[Page 58466]]
over time certain components within a PRD will cease to function as
designed. Thus, RSPA proposed adopting paragraph 9.1.1.1 which would
have required that the operation of the PRD be verified. A number of
commenters opposed this proposal citing its cost and the lack of
incident data supporting adoption of this requirement. Based on the
need to gather more data and review the cost estimates submitted, RSPA
withdrew the proposal and agreed to consider the proposal in a future
rulemaking. RSPA continues to evaluate adopting this industry standard.
Since publication of HM-220A final rule, gas industry
representatives have expressed the view that over time most polymers,
used as seats in PRDs, vulcanize. Vulcanization prevents the devices
from functioning as designed. RSPA solicits information on the
following:
1. Data and comments on the cost, effectiveness and need for
adopting paragraph 9.1.1.1, in CGA Pamphlet S-1.1.
2. Additional incident data from State and local officials
concerning incidents that involved compressed gas cylinders which may
not have been reported to RSPA because the incident did not involve a
hazardous materials carrier or did not meet the reporting criteria
specified in 49 CFR Sec. 171.16.
3. Comments on the need to require PRD manufacturers to certify a
performance range and period for their devices. Thus, a PRD would have
to perform within specific limits throughout a specific life.
Public comments that address these issues will be considered in a
future rulemaking.
IX. Related Rulemakings, Petitions for Rulemaking, and Safety
Recommendations
Docket HM-176A (RIN 2131-AB51). RSPA proposes to amend Sec. 178.46
to remove aluminum alloy 6351-T6 as an authorized material for the
manufacture of DOT 3AL seamless cylinders. In January 1990, at RSPA's
urging, manufacturers of DOT 3AL cylinders voluntarily discontinued the
use of aluminum alloy 6351-T6 because cylinders made of this alloy are
susceptible to cracks that could result in leaks or ruptures.
On July 10, 1987, RSPA published in the Federal Register a safety
advisory and advance notice of proposed rulemaking (ANPRM) (Docket No.
HM-176-A; 52 FR 26027) to inform all persons possessing DOT 3AL (49 CFR
178.46) cylinders, made of aluminum alloy 6351 manufactured by Luxfer
USA Limited, that cracks had developed during service which
occasionally resulted in leakage and loss of cylinder contents. In
addition to the safety advisory, the notice identified those cylinders
at risk, suggested steps that users should take to minimize risks, and
requested industries' comments concerning the extent of the problem and
their suggestions on corrective measures.
RSPA received 31 comments from manufacturers, distributors, and
industrial users of aluminum alloy cylinders. Some commenters submitted
findings of studies for cylinders manufactured with aluminum alloy
6351, including sustained load cracking (SLC) behavior testing. The
majority of the comments and findings concluded that DOT 3AL cylinders
made from aluminum alloy 6351, including cylinders authorized under
exemption DOT-E 7235, pose a greater probability of failure than other
cylinders. Further, information available to RSPA reveals that it is
difficult to detect cracks in these cylinders which adds to the risks.
RSPA published several notices to alert persons to the safety risk
associated with cylinders manufactured to the DOT 3AL specification or
under exemption DOT E-7235 and containing alloy 6351 (50 FR 32944,
August 15, 1985; 58 FR 15895, March 24, 1993, 59 FR 38028, July 26,
1994). Thus, there is sufficient data which demonstrates that this
alloy is not suitable for the manufacture of compressed gas cylinders
and that it should be removed as an authorized construction material.
Petitions for rulemaking. RSPA has received numerous petitions for
rulemaking requesting changes to the cylinder specifications and
related commodity and requalification requirements. These petitions
were held in abeyance and were considered in the development of this
NPRM. Most of the requested changes are included in this NPRM. Because
of the proposals in this NPRM to establish four new cylinder
specifications and to discontinue construction of cylinders to certain
current specifications, some of the requests for changes to the current
regulations are no longer warranted. A summary of the petitions, with
RSPA's comment shown in brackets, are as follows:
----------------------------------------------------------------------------------------------------------------
Petition No. Request
----------------------------------------------------------------------------------------------------------------
0095................................... Consolidate the DOT 3-series specifications to permit unified
specifications. Filed by CGA [Proposed in Secs. 178.69-178.73 for
metric-marked cylinders].
0154................................... Permit filling of non-toxic, nonliquefied flammable gases to 110% of
the cylinder's marked service pressure (including hydrogen). Filed by
CGA [Proposed in Sec. 173.302b for metric-marked cylinders].
0312................................... Align rejection criteria of welded cylinder specifications to permit
testing of second specimen from same lot if first specimen fails.
Filed by the Canadian Transport Commission [Proposed in Sec. 178.81
for metric-marked cylinders].
0324................................... (Request same as P-0312). Filed by the Association of American
Railroads.
0457................................... Revise cylinder repair and rebuilding requirements. Filed by CGA
[Proposed in Sec. 180.211 for all cylinders].
0553................................... Amend Part 178 to change cylinder lot size in each specification. Filed
by CGA [Proposed in Sec. 178.70 for seamless metric-marked cylinders
and in Sec. 178.81 for metric-marked welded cylinders].
0652................................... Revise Sec. 173.302(c)(3) table to add a fifth class of steel for DOT
3 series cylinder tubes. Filed by CGA [Proposed in Sec. 178.70 for
metric-marked cylinders].
0752................................... Amend the table in 178.37-5(a), by adding a column titled ``Authorized
Chemical analysis (designation 10B30).'' Filed by Pressed Steel Tank.
(See DOT E 8311) [Proposed in Sec. 178.70 for metric-marked
cylinders].
0823................................... Incorporate by reference CGA Pamphlets C-1 and C-5. (See also P-981).
Filed by CGA [Incorporated by reference in Sec. 171.7].
0866................................... Revise required sequence for display of specification markings on
seamless aluminum cylinders and allow use of new marking techniques
[Proposed in Sec. 178.69 for metric-marked cylinders].
0953................................... Establish a new specification for manufacture of new welded, stainless
steel cylinders. (See E-4884). Filed by CGA [Proposed in Sec. 178.81
DOT 4M specification].
1040................................... Revise Sec. 173.304(c) and (d)(4) to expand specific gravities for
LPG, at 42% filling density, from 0.504-510 to 0.497-0.510. Filed by
the National Propane Gas Association [Proposed in Sec. 173.304b for
metric-marked cylinders].
1071................................... Permit use of DOT 3AL cylinders for any gas or gas mixture that is
compatible with aluminum. Filed by CGA [Proposed greater use DOT 3ALM
cylinders in Sec. 173.302b].
[[Page 58467]]
1082................................... Revise 173.302(f) to remove 5/6 filling pressure limitation applicable
to DOT 3AL cylinders. Filed by CGA [Proposed in Sec. 173.301a for DOT
3AL cylinders and in Sec. 173.301b for DOT 3ALM cylinders].
1087................................... Establish a new specification for seamless steel cylinders having a
design stress of not more than 90,500 psi and a water capacity of not
more than 150 pounds. (E-9001, 9370, 10047). Filed by CGA [Included in
proposed new DOT 3FM specification in Sec. 178.73].
1090................................... Require that a cylinder requalified by visual inspection must be marked
with the retester's identification number. Filed by CGA [Proposed in
Sec. 180.213].
1189................................... Establish a new low pressure welded stainless steel cylinder
specification. Filed by CGA. Includes P-0953 [Proposed in Sec. 178.81
DOT 4M specification].
1229................................... Revise Secs. 178.36 thru 178.60 to specify procedures for conducting
tensile test. Filed by CGA [Proposed in Sec. 178.69 for metric-marked
cylinders].
1233................................... Permit nondestructive requalification testing of compressed natural gas
(CNG) cylinders. Filed by FIBA [Proposed in Secs. 178.69, 180.207 and
180.209 for metric-marked cylinders and certain nonmetric-marked
cylinders].
1263................................... Revise Sec. 173.34(e)(18) to permit the use of a permanent, non-
transferrable label for retest and inspection markings on fire
extinguishers. Filed by Amerex [Proposed in 180.213].
1277................................... Revise Sec. 173.34(i)(4) to except DOT 4BW cylinders from heat
treatment after replacement of nonpressure attachments. Filed by
Manchester [Proposed in Sec. 180.211 subject to certain conditions].
----------------------------------------------------------------------------------------------------------------
National Transportation Safety Board (NTSB) Safety Recommendations.
I-92-001
Recommends that RSPA require attachments to all DOT authorized
hazardous materials packagings be designed to minimize the risk of
puncturing other hazardous materials packagings during an accident
situation. (Proposed in Sec. 173.301(m))
I-90-008
Recommends that RSPA require hazardous material cargo to be secured
in transportation with adequate restraint systems to prevent ejection
of cargo from vehicles. (Proposed in Sec. 177.840)
I-90-009
Recommends that RSPA require independent inspection of new and
reconditioned low pressure cylinders that are consistent with present
independent inspection requirements for high pressure cylinders
[Proposed for 4M cylinders in Sec. 178.69.]
X. Cross Reference Table
The following table lists the proposed paragraphs or sections and,
where applicable, the corresponding paragraph or section contained in
the current HMR. In some cases, the cross references are to provisions
which are similar to, but not identical with current provisions.
------------------------------------------------------------------------
New section Old section
------------------------------------------------------------------------
107.801
107.803(a)................................ 173.300a(a).
(b)..................................... 173.300a, 173.34(e)(2)(ii)
third sentence.
(c) intro............................... 173.300a(b).
(c)(1).................................. (b)(2).
(c)(2).................................. (b)(3).
(c)(3).................................. (b)(6).
(c)(4).................................. (b)(7).
(c)(5).................................. (a).
(c)(6)
(c)(7)
(d)..................................... (c), (i).
107.805(a)................................ 173.34(e)(2)(ii).
(b)..................................... (e)(2)(ii).
(c)..................................... (e)(2)(ii)(A).
(d)..................................... (e)(2)(ii)(B).
(e)..................................... (e)(2)(ii)(B).
(f)
107.807(a)................................ 173.300b.
(b)..................................... (b).
(c)..................................... (g).
173.301(a)
(a)(1).................................. 173.301(h).
(a)(2).................................. 173.34(e)(1).
(a)(3).................................. (e)(17).
(a)(4).................................. (a)(2).
(a)(5).................................. (e)(1)(ii).
(a)(6).................................. 173.301(k).
(a)(7)
(a)(8)
(a)(9)
(a)(10)................................. 173.301(k).
(b)..................................... 173.34(c).
(c)..................................... 173.301(a).
(d)..................................... (b).
(e)..................................... 173.34(c).
(f)..................................... 173.301(d).
(g) intro
(g)(1) thru (g) (3)..................... 173.301(g)(1) thru (g)(3).
(h)..................................... (g).
(i)
(j)..................................... (i).
(k)
(l)..................................... (j).
(m)
173.301a(a)............................... 173.301(e).
(b)..................................... (e)(1).
(c)..................................... (e)(2).
(d)..................................... (f) .
(e)..................................... 173.34(b).
173.301b
173.302(a)................................ 173.302(a)(4), (a)(5)(i)
thru (iii).
(b)..................................... 173.302(a)(4), (a)(5)(i)
thru (iii).
(c)..................................... 173.301(e).
(d)..................................... 173.301(f).
173.302a(a) intro......................... 173.302(a).
(a)(1).................................. (a)(1).
(a)(2).................................. (a)(2).
(a)(3).................................. (a)(4).
(a)(4).................................. (a)(3).
(a)(5).................................. (a)(4) - (5).
(b)..................................... (c).
(c)..................................... (f).
(d)..................................... (f).
(e)..................................... (d).
173.302b
173.304(a)................................ 173.304(a) intro, (a)(1).
(a)(1).................................. (a)(4).
(a)(2)
(a)(3)
(b)..................................... (b).
(c)..................................... (a) intro.
(d)..................................... (e).
(e)..................................... (f).
173.304a(a)............................... 173.304(a).
(c)..................................... (c).
(d)..................................... (d) .
(e)..................................... (h).
173.304b
173.315(p)................................ 173.301(d)(5).
180.201
180.203
180.205(a)
(b)..................................... 173.34 (e)(2).
(c) intro............................... (e)(1).
(c)(1).................................. (e)(1).
(c)(2)
(c)(3).................................. (c)(3).
(c)(4)
(d)
(e)..................................... (e)(17).
(f)..................................... (e)(3).
(g)..................................... (e)(4).
(h)..................................... (e)(5).
(i)..................................... (e)(6).
180.207
180.209(a)................................ 173.34(e) intro.
(b)..................................... (e)(16).
(c)..................................... (e)(9).
(d)..................................... (e)(10).
(e)..................................... (e)(11).
(f)..................................... (e)(12).
(g)..................................... (e)(13).
(h)..................................... (e)(14).
(i)..................................... (e)(18).
(j)..................................... (e)(19).
(k)
180.211................................... 173.34(g), (i) through (l).
180.213................................... 173.34(c), (e)(7).
[[Page 58468]]
180.215................................... 173.34(e)(2)(v), (e)(8),
(e)(13).
------------------------------------------------------------------------
XI. Summary of Regulatory Changes by Section
Part 107, Subpart I
Section 107.801-107.807
This new subpart would contain procedures whereby persons may seek
approval from the Associate Administrator to be a cylinder requalifer,
an independent inspection agency (IIA), or to have chemical tests or
analysis performed outside the United States for DOT specification
cylinders manufactured outside the United States. These requirements
are contained currently in Secs. 173.300a, 173.34(e) and 173.300b,
respectively. This new subpart would contain the specific requirements.
Current requirements in 49 CFR Subpart H of Part 107 would be
referenced for minimum content of an application, the RSPA office where
an application is to be filed, and the procedures that will be used to
process or terminate an application for approval.
The criteria permit the selection of any person or organization,
foreign as well as domestic, that is technically competent to perform
the prescribed functions and is free from undue influence by persons
involved with the fabrication, ownership or movement of the cylinders
that the applicant, if approved, would be called upon to evaluate and
certify. Under this proposal, RSPA would accept for transportation in
the United States foreign-made cylinders that are similar in
construction to the proposed DOT metric-marked cylinders. As part of
this policy, if the United States recognizes cylinders manufactured
outside the United States and approved by a third party inspector
approved by another government, then equal treatment is expected of
that government relative to cylinders manufactured in the United States
and approved by an IIA approved by DOT. Therefore, a foreign third-
party inspector, who certifies cylinders manufactured outside the
United States, must submit a statement from the competent authority of
the foreign government stating that similar authority is delegated to
manufacturers of metric-marked cylinders in the United States and that
no additional limitations are imposed.
Proposed Sec. 107.803 (current Sec. 173.300a) prescribes
application procedures for approval or renewal as an IIA. These
procedures, contained currently in Sec. 173.300a, would also permit an
IIA, upon approval by the Associate Administrator, to perform other
functions relating to the cylinder requalification requirements
prescribed in Part 180.
Proposed Sec. 107.805 (current Sec. 173.34(e)(2)) prescribes
application procedures for a person seeking an approval to perform
periodic cylinder requalifications. The procedures would be revised and
broadened to apply to any person who performs a function after which
the cylinder is required to be marked with a date as discussed in Part
IV of this preamble under the heading ``DOT approval of cylinder
requalifiers''. Because these provisions would be expanded to apply to
repairers and rebuilders, the terms ``retester'' and ``retester
identification number'' would be replaced with the terms
``requalifier'' and ``requalifier identification number,''
respectively.
Proposed Sec. 107.807 (current Sec. 173.300b) prescribes the
application procedures for issuance or renewal of an approval to
perform chemical analyses and tests outside the United States on DOT
specification cylinders manufactured outside the United States.
Part 171
Section 171.2
Paragraph (d)(3) would be amended to clarify that no one may mark a
requalifier identification number on a cylinder that has not been
requalified in accordance with the applicable requirements.
Section 171.7
This section would incorporate the latest editions of previously
approved CGA Pamphlets, incorporate certain additional ASTM and CGA
standards, and add references to certain publications of the American
National Standards Institute (ANSI).
Section 171.8
Definitions for ``metric-marked cylinder'' and ``nonmetric-marked
cylinder'' would be added.
Section 171.12
Paragraph (b)(15) would be revised to include references to
Sec. 171.12a(b)(13).
Section 171.12a
On August 18, 1998, RSPA issued a notice of proposed rulemaking
[Docket HM-215C; 63 FR 44312] which proposed to revise paragraph
(b)(13) to provide reciprocity for certain Canadian specification
cylinders to be transported within the United States. This HM-215C
proposed change is reprinted here for the benefit of readers.
Part 172
In the Sec. 172.101 Table, in column (8b) for the entries
``Cyanogen'', ``Germane'', and ``Iron Pentacarbonyl'' would be revised
to specify packaging authorization sections that are consistent with
their toxic properties.
Part 173
Section 173.34
The provisions in this section would be relocated to subpart I of
part 107, Sec. 173.301 and subpart B of part 180, as appropriate, and
Sec. 173.34 would be removed. All references to Sec. 173.34 in the HMR,
approximately 150 in number, would be removed and replaced with the
appropriate section reference.
Section 173.40
The requirements for toxic materials packaged in cylinders would be
revised to include an additional performance criteria for puncture
resistance. The requirements in Sec. 173.40 currently apply only to
materials in Hazard Zone A. All requirements except the controls on
closures would be expanded to Hazard Zone B materials. RSPA requests
comments on whether cylinders with Hazard Zone B materials should be
required to meet the same closure requirements required for Hazard Zone
A.
As discussed earlier in this preamble, DOT 3AL cylinders made of
aluminum alloy 6351-T6 are susceptible to sustained load cracking (SLC)
in the neck and shoulder area of the cylinder head and, therefore, may
leak in transportation. Leaks of Toxic Inhalation Hazard (TIH)
materials pose a significant threat to health and safety. At least two
major gas suppliers have voluntarily stopped using these cylinders in
TIH gas services. The proposed regulation will reduce the risk to
health and safety associated with TIH materials leaking through cracks
in cylinders. RSPA proposes that this regulation be imposed on the
effective date of this rule. After that date, cylinders made of 6351
alloy may not be filled and offered for transportation in TIH service.
Cylinders filled prior to that date may be offered for transportation
and transported to their ultimate destination and, when necessary,
cylinders containing unused gas may be returned to the person who
filled the cylinder.
Section 173.163
The requirements for nonmetric-marked cylinders containing hydrogen
fluoride would be amended to require ultrasonic examination as the only
authorized requalification method. This
[[Page 58469]]
proposal is based on the fact that the presence of moisture in a
cylinder containing hydrogen fluoride causes rapid corrosion of the
cylinder wall. Since removal of all moisture after hydrostatic testing
is very difficult, the current requirements authorize only the external
visual inspection in lieu of hydrostatic testing and internal visual
inspection. At the time the requirement was last amended, no other
alternative examination was available to reliably examine the cylinder
without introducing moisture into the cylinder. An ultrasonic
examination, to examine the internal sidewall for defects, can be
performed without introducing moisture to the cylinder. This section
also would be amended to include metric-marked cylinders for use in
hydrogen fluoride service.
Section 173.192
The title of this section would be revised to reflect that
requirements are applicable to Hazard Zone A gases. The restriction on
aluminum cylinders by highway and rail would be extended beyond arsine
and phosphine to include all Hazard Zone A gases. Paragraph (c) would
be amended to authorize alternative leakage tests having an equivalent
level of sensitivity as the current water bath leakage test, upon
written approval from the Associate Administrator. Currently without
exception, cylinders containing any amount of phosgene gas must be
subjected to a water bath leakage test prior to offering them for
transportation.
Section 173.198
An editorial change would be made to paragraph (a).
Section 173.226
Paragraph (a) would be revised to include only seamless
specification cylinders conforming to all requirements of Sec. 173.40.
Currently, Division 6.1, Hazard Zone A materials may be shipped in any
DOT specification cylinder except 8, 8AL and 39. RSPA believes that
this must be corrected in order to require these high hazard materials
to be transported in cylinders with a higher level of safety.
Section 173.227
Paragraph (a) would be revised to include only seamless and welded
specification cylinders conforming to the requirements of Sec. 173.40.
Section 173.228
Paragraph (a) would be amended to include metric-marked
specification cylinders and to require that cylinders used for bromine
pentafluoride and bromine trifluoride in Hazard Zones A and B materials
must conform to Sec. 173.40 as required for similar materials.
Sections 173.300a-173.300c
The provisions in these sections would be relocated to new Subpart
I of Part 107 and Secs. 173.300a, 173.300b and 173.300c would be
removed.
Sections 173.301-173.301b
Current Sec. 173.301 would be revised and proposed Secs. 173.301a
and 173.301b would be added. Section 173.301 would contain the general
shipper requirements for the use of specification cylinders that are
currently in Sec. 173.34 and the standard requirements for cylinders
that are currently in Sec. 173.301. These requirements include general
prefill requirements, maintenance and legibility of markings, PRD,
valve protection, manifolding of cylinders and the charging of foreign
cylinders. A derivation table showing the relocation of the
requirements appears in Part X of this preamble.
Certain other changes would be made to Sec. 173.301. The cargo tank
manifolding requirements that are currently in Sec. 173.301(d) would be
removed and placed with other cargo tank requirements in Sec. 173.315.
Proposed paragraph (a)(6) would prohibit the offering for
transportation and transportation in commerce of a filled cylinder
having a specified service life after its service life has expired.
This requirement will ensure cylinders that may be unsafe are removed
from service for transportation of hazardous materials.
Proposed paragraph (d) contains the general prohibition, that is
currently contained in paragraph (a), against filling a cylinder with
gases that are capable of combining chemically with each other or with
the cylinder material so as to endanger its serviceability. This
provision would be expanded to prohibit the use of DOT 3AL cylinders
made of aluminum alloy 6351-T6 for gases having pyrophoric properties.
Leaks of gases having pyrophoric properties, such as, silane, would
cause spontaneous flame and pose a significant threat to the health and
safety. A transition period of six months after the effective date of
the final rule would be provided for cylinders filled prior to the
specified date.
Proposed paragraph (f) contains PRD system and setting
requirements. The general purpose of a hazardous material packaging is
to prevent the unintentional release of a hazardous material under
normal conditions of transportation, including mishandling and minor
traffic accidents. Also, the packaging standards for cylinders are
designed to prevent failure of a cylinder from over pressurization,
particularly, when it retains substantial stored energy. Thus, a
balance must be set between competing interests for keeping a hazardous
material, particularly Division 2.1 and 2.3 gases and Division 2.2
gases with oxidizing properties, in a packaging and allowing such a
material to escape in order to prevent the packaging from rupturing.
Under current regulations, the type and setting of PRD systems are
established by CGA Pamphlet S-1.1. CGA Pamphlet S-1.1 allows a PRD
setting to be 75% to 100% of test pressure of the cylinder. Based on
RSPA's analysis of the currently authorized settings, a fully charged
nonmetric-marked DOT-3 series gas cylinder at 130 deg.F operating
temperature will likely release hazardous gases when the PRDs,
conforming to the authorized tolerances on device function, are set
below test pressure. RSPA believes this creates a serious threat to
safety by allowing an improper balance between keeping the hazardous
material in the package and preventing the cylinder from rupturing. In
contrast, RSPA does not believe this condition applies to DOT-4 series
cylinders because the ratio of test pressure to service pressure is 2:1
as compared to 1.67:1 for DOT-3 series cylinders.
To correct this condition, RSPA is proposing a PRD setting of 100%
of the marked test pressure for metric-marked and nonmetric-marked DOT-
3 series cylinders. To allow users sufficient time to change their
nonmetric-marked cylinders to meet the new PRD setting requirement,
RSPA is proposing that each cylinder be brought into compliance at the
first requalification of the cylinder after the effective date of the
final rule.
RSPA believes a setting of 100% of test pressure for a PRD is a
reasonable balance between keeping a gas in a cylinder and preventing a
cylinder from rupturing in the event of a fire or overfill. PRDs
designed to release at not less than test pressure will eliminate the
possibility of gas release through the relief device at a temperature
less than or equal to 54 deg.C (130 deg.F). At the same condition,
test pressure, the factor of safety for cylinder rupture is 1.6. As a
result of discussions with gas shippers, RSPA believes many major
shippers of DOT-3 series cylinders are currently setting PRDs at 90-
100% of test pressure for toxic and flammable gases. Because it is
common practice for many shippers of DOT-3 series cylinders to replace
the PRD at the time of a
[[Page 58470]]
cylinder's requalification, RSPA believes the proposal will result in
minimal incremental cost. For most gases, RSPA believes the increased
PRD setting will not significantly impact the performance of cylinders
in bonfire tests. RSPA requests the following:
1. Data on the performance of PRDs set at test pressure in bonfire
tests.
2. Comments on any gases or cylinders where a 100% of test pressure
setting could prevent a cylinder from passing a bonfire test.
3. Comments on the need to requalify PRDs in a bonfire test.
Proposed paragraph (h) would contain the cylinder valve protection
requirements that are currently in paragraph (g). These requirements
would be revised to require a performance-oriented approach to valve
assembly protection. A six foot drop test would be required to verify
that each cylinder valve (with or without protection assembly) has
sufficient strength to survive falls incidental to handling in
transportation. An acceptable drop test result would be that no leakage
occurs after the cylinder is dropped, although the cylinder may show
damage. A similar drop test is currently required for all non-bulk
performance-oriented packagings to ensure that the packages can
withstand normal conditions of transportation. RSPA believes that
cylinders should be held to at least the same level of performance as
drums and fiberboard boxes. A period of five years is proposed in
paragraph (h)(1)(i) to provide a smooth transition to meet this
performance requirement.
Proposed paragraph (k) would be added to permit foreign cylinders
to be imported into the United States and transported within a single
port area subject to certain conditions.
Proposed paragraph(m) would be added to prohibit cylinder
attachments with sharp features that may cause damage to other freight.
This new provision is in response to NTSB Recommendation I-92-001 with
respect to cylinders. Attachments for other hazardous material
packaging types will be addressed in a separate rulemaking action.
Proposed Sec. 173.301a would contain the current requirements
pertaining to the pressure in a nonmetric-marked cylinder at 70 deg.F
and 130 deg.F. It would also contain a grandfather provision that is
currently in Sec. 173.34(b).
Proposed Sec. 173.301b contains additional general requirements for
metric-marked cylinders used for nonliquefied (permanent) gases.
Definitions would be added for ``critical temperature,'' ``dissolved
gas,'' ``filling factor of liquefied compressed gas,'' ``high pressure
liquefied compressed gas,'' ``low pressure liquefied compressed gas,''
``permanent (non-liquefied compressed) gas,'' ``safety factor,'' and
``settled pressure.'' These proposed definitions, which are used in ISO
Standard 11622, will provide for harmonization with the international
standards.
Sections 173.302-173.302b
Current Sec. 173.302 would be revised and proposed Secs. 173.302a
and 173.302b would be added. Proposed Sec. 173.302 prescribes the
general requirements that would apply to filling a specification
cylinder with a nonliquefied (permanent) compressed gas.
Proposed 173.302a prescribes requirements for filling a nonmetric-
marked cylinder with a nonliquefied compressed gas, i.e., the current
requirements in Sec. 173.302. In addition, RSPA proposes to remove the
\5/6\ filling pressure limitation for DOT 3AL cylinders in carbon
monoxide service, in response to a CGA petition (P-1082). CGA furnished
information to support its conclusion that, although evidence shows
that carbon monoxide can cause stress corrosion cracking in steel
cylinders, there is no evidence that carbon monoxide causes corrosion
cracking or carbonyl formation in aluminum cylinders.
Proposed Sec. 173.302b prescribes requirements for filling a
metric-marked cylinder with permanent gas. Because a metric-marked
cylinder is stamped with the test pressure in bar, the fill pressure is
calculated from the marked test pressure. The charge pressure for a
metric-marked cylinder is \2/3\ of the test pressure for seamless DOT
3M, 3FM and 3ALM cylinders, and \1/2\ of the test pressure for welded
DOT 4M cylinders. The NPRM proposes a uniform standard which reduces
the possibility of overfilling and allows the gas industry to ship an
additional 1.5% gas. Because the NPRM proposes that the cylinder be
marked and charged in accordance with ISO Standard 11622, it would
facilitate shipments of hazardous material in DOT specification
cylinders internationally.
Section 173.304-173.304b
Current Sec. 173.304 would be revised and proposed Secs. 173.304a
and 173.304b would be added. Proposed Sec. 173.304 prescribes general
requirements that would apply to filling a specification cylinder with
a liquefied gas.
Proposed Sec. 173.304a prescribes specific requirements for filling
a nonmetric-marked cylinder with a liquefied gas, i.e., the
requirements that are currently in Sec. 173.304. Currently,
Sec. 173.304 limits the filling of a cylinder with a liquefied
compressed gas based on the maximum expected operating temperature (130
deg.F) and the minimum specific gravity of the liquid at 60 deg.F.
The maximum filling densities for many gases are prescribed in a table
that would be retained in the HMR in Sec. 173.304a for nonmetric-marked
cylinders.
The current regulation defines a liquefied compressed gas to be
partially liquid at an operating temperature of 20 deg.C (68 deg.F)
and authorizes a filling limit based on a wide range of critical
temperatures. Therefore, the safety factor derived from filling limits
is conservative for some gases and marginal for other gases. In
addition, the current regulations limit the internal volume of a DOT-39
specification cylinder to 75 cubic inches when used for liquefied
petroleum gases. This requirement is revised to apply to all liquefied
flammable gases and appears in proposed Sec. 173.304a(a)(3). In
proposed Sec. 173.304b for metric-marked cylinders, filling limits are
based on the maximum operating temperature and filling factor. Instead
of a maximum filling density table, the proposed filling limits are
based on a filling factor which is directly related to the critical
temperature of the liquefied compressed gas. The proposed filling
limits are applicable to all liquefied compressed gases. Under the
proposed filling limits, the filling factor is defined based on the
critical temperature and the operating condition of each individual
gas. Therefore, the proposal enhances the level of safety and allows
the gas industry to fill the cylinders with more product.
Section 173.334
This section would be amended to include metric-marked
specification cylinders.
Section 173.336
This section would be amended to include metric-marked
specification cylinders.
Section 173.337
This section would be amended to include metric-marked
specification cylinders.
Part 177
Sec. 177.840 Class 2 (Gases) Materials
RSPA proposes to revise paragraph (a)(1) to allow horizontal
loading of cylinders containing Class 2.2 materials. In addition, the
horizontal loading of Class 2.1 and Class 2.3 materials would be
permitted for cylinders designed so that the inlet to the PRD is
located in the
[[Page 58471]]
vapor space and provided that the cylinders are properly secured during
transportation.
This paragraph also would require the use of cylinder restraint
systems to reduce the likelihood of the cylinders being ejected from
the vehicle in event of an accident. This proposal is based on a NTSB
Recommendation I-90-008, that urges RSPA to require hazardous materials
packages to be secured with adequate cargo restraint systems to prevent
their ejection from the vehicle during transportation. NTSB made the
recommendation following an accident in Collier County, Florida that
involved a number of cylinders, containing a poisonous by inhalation
gas, being ejected from an overturned tractor-flatbed semitrailer.
Considering the wide variation in cylinder sizes, and the various types
of restraints that would be required, RSPA solicits information on
anticipated safety benefits and the costs of requiring the use of
restraint systems, particularly on small businesses.
Part 178
Section 178.46
As discussed in Part IX of this preamble, the tables in paragraph
(b)(4) would be revised to remove aluminum alloy 6351 as an authorized
material for the manufacture of DOT 3AL seamless cylinders. In
addition, in Table 1, several changes would be made to the chemical
composition limits for 6061 alloy for consistency with limits stated in
The Aluminum Association Standards and Data, 1993 edition. The Si
maximum that is currently stated as 0.80% would be revised to read
0.8%, the Fe maximum that is currently stated as 0.70% would be revised
to read 0.7%, the Mg minimum that is currently stated as 0.80% would be
revised to read 0.8%, and the Mg maximum that is currently stated as
1.20% would be revised to read 1.2%. Finally, Table 1 limits the
chemical composition of Pb (lead) and Bi(bismuth) to 0.01. RSPA
proposes to change these limits to 0.005.
Section 178.69
This new proposed section contains general design and manufacturing
requirements applicable to all metric-marked DOT specification
cylinders. This proposed section contains much of the same information
as the current Sec. 178.35, including compliance, inspection and
analyses, duties of inspector, PRDs, and markings; however, proposed
Sec. 178.69 is extended to address definitions, authorized material,
threads, and tests. Thus, Sec. 178.69 would simplify the regulations in
that all information common to metric-marked cylinders will be
centrally located, and will allow the simplification and streamlining
of the individual cylinder specifications proposed in Secs. 178.71,
178.72, 178.73 and 178.81.
Paragraph (b) will define common terms for clarity and consistency.
The addition of the new definition for ``volumetric expansion test''
will clarify RSPA's meaning of the many terms used by industry to
describe pressure testing.
Paragraph (c) specifies the requirements for inspection and
analyses. RSPA proposes that all DOT 4-series metric-marked cylinders
have inspection and analyses performed by an independent inspection
agency.
In paragraph (e), duties of the inspector, RSPA proposes a change
to allow the inspector to obtain a certified cast or heat analysis from
the cylinder manufacturer in addition to the material producer or
supplier, as needed. The current regulations require the inspector to
verify that the material of construction meets the requirements of the
applicable specification by either making a chemical analysis of each
heat of material; obtaining a certified chemical analysis from the
material manufacturer for each heat of material; or by making a check
analysis of a sample from each coil, sheet, or tube if an analysis is
not provided by the material manufacturer for each heat of material.
These alternative methods for verifying compliance are something raised
by independent inspectors to require cylinder manufacturers to perform
check analyses when readily available information may be used. The
proposed regulation would allow cylinder manufacturers to use analyses
obtained from the mill to verify the material conforms to standards for
the cylinder specification.
Paragraph (f) specifies performance-oriented requirements for
threads. These requirements would allow the manufacturer to design the
threads in conformance with any appropriate standard as long as certain
thread shear strength limits are met.
Paragraphs (h) and (i) list all tests that apply to metric-marked
cylinders. A new approach for the metric-marked cylinders is the
categorization of design qualification tests (paragraph (h) in addition
to production tests in paragraph (i)). These paragraphs include
criteria for each test as well as acceptance criteria. The individual
cylinder specifications prescribe which tests in Sec. 178.69 apply to
each specification, as well as any unique test requirements or
acceptable results. Centralizing all test information in one location
reduces repetition in the regulations and reduces the likelihood of
inconsistent requirements in the specifications. The requirement that
new metric-marked cylinders have cycle testing performed during design
qualification incorporates current industry practice. RSPA believes
that the cycle test is an important design performance test that
assesses cylinder fatigue life and, therefore also, proposes this
requirement for welded cylinders.
Paragraph (i)(12) contains requirements for ultrasonic examination
(UT); a non-destructive test method designed to detect surface and
subsurface flaws and to measure the thickness of a cylinder and the
size of a flaw or crack. The UT equipment has the capability to detect
the presence of discontinuities on or even within the cylinder
sidewall, shoulder, or bottom. UT would be required for all seamless
and some welded metric-marked cylinders at the time of manufacture.
Paragraph (k) prescribes marking requirements. A significant change
for the new metric-marked cylinders is marking with the test pressure,
rather than service pressure, expressed in bar. To communicate vital
information to requalifiers, metric-marked cylinders that require UT
examination during requalification must be marked ``UT'' as well as
with the minimum wall thickness. Other markings, such as country of
origin, will be required for metric-marked cylinders; thereby making
them more acceptable for transportation of hazardous materials in
international commerce.
Paragraph (l) includes a prohibition on coatings that may interfere
with inspections and tests, or that allow moisture to accumulate
between the cylinder wall and the coating. This provision is RSPA's
response to potential threats to safety associated with coating
materials, such as vinyl, which promote corrosion.
Section 178.70
This proposed section groups the common requirements that apply to
all DOT 3 series metric-marked seamless cylinders (DOT 3M, DOT 3ALM,
and DOT 3FM).
Paragraph (c) specifies materials for 3 series cylinders.
Authorized materials are located in Appendix A, Table 1 for steel and
nickel and Table 2 for aluminum. The steel compositions authorized
include two carbon manganese type, one chrome moly type steel, and one
stainless steel type. The aluminum composition is a 6061 alloy. These
compositions are broad enough to cover most material specifications
currently in use.
[[Page 58472]]
Paragraph (e) specifies wall thickness requirements. The current
DOT 3AAX requirement in Sec. 178.37(a)(2)(i) that adresses additional
design loads due to bending is proposed in this general section for all
DOT 3-series metric-marked cylinders. The inclusion of this requirement
sets a precedent in the HMR by allowing manufacturers the flexibility
to adapt any metric-marked cylinder specification to a ``tube trailer''
type cylinder.
Section 178.71
This section proposes the new DOT 3M metric-marked cylinder
specification. This specification combines aspects of the current DOT
3A, 3AX, 3AA, 3AAX, 3B, and 3BN specifications.
Proposed paragraph (c) authorizes construction using steel,
stainless steel, and nickel. The carbon manganese composition
authorized encompasses the steel currently used for DOT 3A
specification cylinders. The inclusion of the stainless steel
composition for a seamless cylinder will eliminate the need for many
exemptions.
Section 178.72
This section proposes the new DOT 3ALM metric cylinder
specification. This specification is very similar to the current DOT
3AL except that aluminum alloy 6351 is not authorized as a material of
construction.
Section 178.73
This section proposes the new DOT 3FM metric-marked cylinder
specification. The proposed DOT 3FM cylinder is designed to a high
stress level similar to the DOT 3T, and incorporates the strong
structural integrity of the DOT 3AA cylinder. This specification meets
many of the requirements of the ISO Standard 9809-2 cylinder, which
should make it readily acceptable in international commerce. The
authorized materials of construction are Grade B, a chrome molybdenum
type steel currently authorized for 3T cylinders and Grade E a new
chrome molybdenum type steel. Steels such as Grade E with higher
ultimate strength levels (above 115,000 psi) are currently authorized
under exemption. Because the most critical failure mode is cracking,
these cylinders will be subjected to UT examination at the time of
manufacture and requalification.
Section 178.81
This section contains specific requirements for the proposed DOT 4M
metric-marked cylinder specification. This specification combines
aspects of the current DOT 4B, 4BA, 4BW, 4B240ET, 4E, 4D, 4DA, 4DS and
4AA480 specifications. The maximum design test pressure is 140 bar
(2030 psi). This represents a pressure of more than double what is
currently authorized for welded cylinders, except the DOT 4DA and 4DS
specification, which have a maximum test pressure of 1800 psi.
Authorized materials would include aluminum alloy 5154 currently used
for the DOT 4E specification cylinder, as well as carbon, HSLA,
stainless, and 4130X steels. For DOT 4M specification cylinders with a
test pressure of 70 bar or more, the welds must be 100% radiographed to
provide assurance of the joint quality. Manufacturers of DOT 4M
specification cylinders would have the option of performing an
ultrasonic examination in lieu of the radiographic examination.
RSPA solicits comments on the need for a higher performance welded
cylinder specification than what is proposed in this NPRM. Comments are
also requested as to whether such a higher performance specification
should be distinguished from the lower performance by pressure, or by
material strength, or some other performance standard. RSPA is
currently considering a cylinder specification with a design test
pressure of either more than 140 bar (2030 psi) or with an ultimate
tensile strength of 830 Mpa (121,000 psi) or higher.
Part 180
Part 180, Subpart C
This new subpart would prescribe requirements for the continuing
qualification, maintenance, repair and rebuilding of DOT specification
and exemption cylinders. Most of the requirements are currently
contained in Secs. 173.34 and 173.301. Readers should refer to the
references under Part X of this preamble for the citation of the
corresponding provision that is similar to the current provision
contained in the HMR. The proposed requirements include DOT metric-
marked cylinders.
Section 180.203
This section contains definitions for terms used throughout Subpart
C. Some of these definitions are ``commercially free of corrosive
components,'' ``condemn,'' ``defect,'' ``rejected cylinder,'' and
``volumetric expansion test.''
Section 180.205
This section prescribes general requirements for the continuing
qualification and use of cylinders and for each person performing a
cylinder requalification function.
Section 180.207
This section prescribes requirements for the periodic
requalification of metric-marked specification cylinders. Proposed
Table I specifies the periodic requalification requirements. The
standard requalification period is once every five years, with extended
requalification periods provided for cylinders used exclusively to
transport certain gases. For example, when used exclusively for
noncorrosive, nontoxic (LC50 of not less than 5000 ppm) gases, DOT 3M,
3ALM, and 3FM specification cylinders must be requalified at least once
every ten years. Similarly, a DOT 4M specification cylinder must be
requalified at least once every 15 years. DOT 3M and 4M specification
cylinders used exclusively as fire extinguishers and meeting the
limitation of special provision 18 must be requalified at least once
every twelve years, as currently required for nonmetric-marked DOT
specification cylinders used as fire extinguishers.
All DOT 3M, 3ALM, 3FM and 4M specification cylinders must be
requalified using the ultrasonic examination, instead of a volumetric
expansion test. A DOT 4M specification cylinder, with a marked test
pressure of 70 bar or less and having a tensile strength less than 830
Kpa (120,000 psi), may be subjected to a volumetric expansion test in
lieu of an ultrasonic examination. Ultrasonic examination improves
safety by automating the identification and measurement of wall
thickness, pitting and cracking. It improves the probability of
detection for internal pits and cracks over current internal visual
inspection. Ultrasonic examination also reduces inspection and labor
costs, cleaning costs and waste water by allowing cylinder
requalification without removing the valve and purging the cylinder's
contents, and without the deliberate introduction of water into the
cylinder.
Comments are invited on the proposed requirements for ultrasonic
examination of cylinders. RSPA also solicits information on industry
practices in this area, the costs and benefits for using UT
examinations and the pass/fail criteria in Table II.
Section 180.209
This section prescribes requirements that are currently contained
in Sec. 173.34(e) for the periodic requalification of nonmetric-marked
specification cylinders. The current rule for the requalification of
most DOT specification and exemption cylinders requires a volumetric
expansion test, external and internal visual inspections
[[Page 58473]]
which are not suitable for detecting a buried or internal crack.
In proposed paragraph (a)(1), note 2 following the table requires
detection and measurement of the sidewall cracks in DOT 3T and 3HT
cylinders at each requalification period by an approved non-destructive
test (NDT) method. Cracks in these cylinders can be detected by using a
suitable NDT method, such as acoustic emissions or appropriate shear
wave ultrasonic examination. Because the ultimate tensile strength
(UTS) of DOT 3T and 3HT cylinders are above 7,900 Mpa (155,000 psi),
crack growth due to stress corrosion and fatigue can occur during
normal service. An undetected crack can grow to a critical size and
result in a catastrophic failure. Manufacturers of specificition DOT 3T
and other high strength exemption cylinders are required to perform UT
examinations at the time of manufacture.
Proposed paragraph (a)(2) allows for nonmetric-marked specification
cylinders to be ultrasonically examined as an alternative
requalification method. An external visual inspection is required to be
conducted in conjunction with the UT examination. The requalification
period for nonmetric-marked cylinders is the same as required in Table
I of this proposed section.
Section 180.211
This section prescribes repair, rebuild and heat treatment
requirements currently prescribed in Secs. 173.34(g) thru 173.34(l),
with certain revisions. These requirements are standardized and
simplified.
Section 180.213
This section contains marking requirements presently contained in
Sec. 173.34(e)(7), with certain revisions.
A new requirement for all specification cylinders would be added to
identify the type of inspection, test, or work performed on a cylinder.
This new requirement would enable shippers, carriers, and enforcement
personnel to readily determine the type and date of each inspection or
test, or whether any repair or rebuilding work has been performed on a
cylinder.
The methods for marking cylinders would permit stamping, engraving,
scribing or any other method approved in writing by the Associate
Administrator for HMS. In response to a NPGA petition, RSPA also
proposes allowing use of pressure sensitive labels to display the
requalification markings on fire extinguishers. However, RSPA is also
soliciting comments on whether there are any methods that should or
should not be authorized for application of requalification markings.
Currently, after a cylinder passes the requalification volumetric
expansion test, internal and external visual examinations, etc., the
RIN holder stamps the month and year of the test and its RIN on the
cylinder. This marking is normally accomplished with steel stamps.
However, RSPA has granted exemptions, such as E-11372, authorizing
certain fire extinguishers and fiber-wrapped cylinders to display the
requalification markings using labels. RSPA is considering whether to
incorporate new marking methods for DOT specification cylinders
following the requalification process.
RSPA requests comments on the feasibility, costs and benefits of
alternative marking methods, and whether affected persons believe there
is justification for RSPA to adopt alternative methods.
Section 180.215
This section contains the reporting and record retention
requirements currently prescribed in Sec. 173.34(e)(8), with certain
revisions.
The retester authorization record requirements in current
Sec. 173.34(e)(8)(i) would be revised to include all cylinder
requalifiers who inspect, test, repair, or rebuild cylinders. In
addition, proposed paragraph (d)(1) requires that records covering any
work involving welding or brazing repairs, or the building or reheat
treatment of cylinders must be retained by the cylinder requalifier for
15 years. The requalifier would be required to retain inspection and
test records until expiration of the inspection or requalification
period or until the cylinder is again requalified, whichever occurs
first. Records of any welding or brazing repair, rebuilding or reheat
treatment would be required to be retained for 15 years.
XII. Regulatory Analyses and Notices
A. Executive Order 12866 and DOT Regulatory Policies and Procedures
This proposed rule is considered a significant regulatory action
under section 3(f) of Executive Order 12866 and was reviewed by the
Office of Management and Budget. The rule is considered significant
under the Regulatory Policies and Procedures of the Department of
Transportation (44 FR 11034) because of public interest. A preliminary
regulatory evaluation is available for review in the docket.
B. Regulatory Flexibility Impact
General
The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires an
agency to review regulations to assess their impact on small entities
unless the agency determines that a rule is not expected to have a
significant economic impact on a substantial number of small entities.
RSPA is unable, at this time, to certify that this proposed rule will
not have a significant impact on a substantial number of small
entities. RSPA has performed an Initial Regulatory Flexibility Analysis
(IRFA) of this proposed rule's potential impact on small entities, and
the assessment has been placed into the public docket for this
rulemaking. Written public comments that clarify the degree of
potential impacts on affected small entities are requested.
IRFA Summary
The Regulatory Flexibility Act is concerned with identifying the
economic impact of regulatory actions on small businesses and other
small entities. Unless alternative definitions have been established by
the agency in consultation with the Small Business Administration, the
definition of ``small business'' has the same meaning as under the
Small Business Act. As RSPA has established no special definition, the
agency employs thresholds published under criteria in 13 CFR 121.101,
e.g., 500 employees for cylinder manufacturers (SIC 3443--Fabricated
Plate Work (Boiler Shops) and SIC 3462 Iron and Steel Forgings).
Need for the proposed rule. As indicated throughout the preamble to
this proposed rule, current requirements for the manufacture, use, and
requalification of cylinders can be traced to standards first applied
in the early 1900's. The regulations were subsequently revised in a
piecemeal fashion, with adjustments being made to address particular
situations and problems on a case-by-case basis. This notice represents
RSPA's first comprehensive review of requirements pertaining to the
transportation of compressed gases in cylinders and spheres. This
action is being taken to: (1) Simplify requirements for the production
of new cylinders, (2) provide flexibility in the design, construction
processes and permitted use of cylinders, (3) adopt advanced
technological processes and procedures for cylinder manufacturing and
requalification, (4) achieve an increased level of safety through
simplification of the rules and regulations, (5) reduce the need to
issue, and renew, exemptions
[[Page 58474]]
that permit variances from detailed specifications concerning materials
of construction, design, and manufacturing processes, and (6)
facilitate international commerce in the transportation of compressed
gases.
Objectives and legal basis for the proposed rule. The intended
effect of this action is to reduce threats to health, safety and
property in the transportation of hazardous materials, particularly
flammable, toxic and other compressed gases. Federal hazardous
materials transportation law (49 U.S.C. 5101 et seq.) directs the
Secretary of Transportation to prescribe regulations for the safe
transportation of hazardous materials in intrastate, interstate and
foreign commerce. Section 5103(b) specifies that the regulations shall
apply to persons transporting hazardous materials in commerce; causing
hazardous materials to be transported in commerce; or manufacturing,
fabricating, marking, maintaining, reconditioning, repairing, or
testing a packaging or container that is represented, marked,
certified, or sold by such persons as qualified for use in transporting
hazardous material in commerce.
Identification of potentially affected small entities. 1.
Businesses likely to be most affected by this proposed rule are
manufacturers of specification DOT-3 and DOT-4 series cylinders (SIC
3443 and SIC 3462). Currently, RSPA estimates there are 40
manufacturers of specification DOT-3 and DOT-4 series cylinders. Of
that number, approximately 29 are ``small businesses'' under the Small
Business Act.
In the case of approximately eleven (11) manufacturers (five (5) of
whom are small businesses) of high-pressure (specification DOT-3
series) cylinders there should be little or no burden attributed to
requirements contained in this proposed rule, as many of these new
processes and technological innovations have already been adopted as
part of their own quality management program.
In addition to the above, there are another twenty-nine (29)
cylinder manufacturers (twenty-four (24) of whom are small businesses)
identified in RSPA's database of registered markings for packaging
manufacturers, and/or holders of exemptions that authorize the
manufacture, marking, and sale of cylinders that do not fully conform
to specifications for the DOT-3 and DOT-4 series. Eight (8) of these
cylinder manufacturers (including five (5) that meet the criterion of a
small business) are members of the Compressed Gas Association (CGA),
one of the primary initiators of petitions for rulemaking to revise the
HMR for greater consistency with regulations of the world's leading
industrial nations. It is RSPA's understanding that all CGA members
support proposed revisions contained in the CGA petitions. However,
that leaves another twenty-one (21) non-CGA-member cylinder
manufacturers, of which RSPA assumes at least 90% (approximately
nineteen (19)) meet the SBA criterion for a small business, that would
be affected by the proposed rule.
Some small entities may experience an adverse economic impact
attributed to the proposed rule's prohibition on the manufacture of
non-metric-marked specification DOT-3 and DOT-4 series cylinders after
a future date (five years from the effective date of a final rule).
Prior to that date, small entities would, at their own discretion, be
permitted to manufacture (1) non-metric-marked cylinders only, (2)
metric-marked cylinders only, or (3) a combination of non-metric-marked
cylinders and metric-marked cylinders. However, after the phase-out
date, these small entities may manufacture DOT-3 and DOT-4 cylinders
conforming to metric-marked specifications only.
RSPA anticipates that, upon review of these proposed requirements,
some small entities currently producing specification DOT-3 or DOT-4
series cylinders may determine that it is not economically feasible to
continue this line of products. For example, RSPA estimates the average
annual cost of the proposed requirement for an independent inspection
agency to observe cylinder manufacturing operations and processes at
$59,286 per facility. However, that average is calculated on the basis
of a wide range of costs for individual facilities that produce
specification DOT-4 series cylinders (e.g., $5,000 for an occasional
production run to $100,000 for a manufacturer that operates a dedicated
line). For manufacturers that produce a relatively large volume of
these cylinders the CGA estimates the additional cost of manufacturing
attributed to this provision will be an additional 10 cents per
cylinder. For a completed 20-pound propane cylinder that currently
sells for approximately $25 (retail price), RSPA expects that the added
expense would not be prohibitively costly to the manufacturer or to the
ultimate consumer.
RSPA understands that the production of specification DOT-3 and
DOT-4 cylinders by some manufacturers that are small businesses
oftentimes is but one of a wide-range of pressure vessels, or other
products, in the company's product line. Knowing the importance of
specification DOT-3 and DOT-4 series cylinders to the viability of
these small entities, is critical to RSPA's determination of whether
this rule may have a significant economic impact on a substantial
number of small manufacturing companies. Small entities are, therefore,
specifically invited to provide comments on the economic impact of the
proposed rule on their overall operations.
2. In addition to cylinder manufacturers, there are approximately
1,400 businesses currently engaged in the periodic requalification of
high-pressure cylinders. Here, also, RSPA conservatively estimates that
at least 90 percent of these requalifiers are small businesses. This
number includes businesses that manage large fleets of cylinders, such
as cylinders charged with propane to power forklift trucks, and for use
by retail customers through cylinder exchange programs. Still other
companies, generally thought to fall within SIC 7389 (business
services, not elsewhere classified), manage fleets of cylinders used in
(1) carbon dioxide service for carbonated soft drinks, (2) fire
extinguisher service, and (3) compressed air/oxygen breathing equipment
used in recreational diving operations, as well as by emergency
services personnel, like firefighters. All of these businesses are
currently approved to requalify cylinders through performance of the
hydrostatic pressure test.
The proposed rule would require each business to determine whether
it should: (1) upgrade test equipment from the hydrostatic type to
ultrasonic examination type to be able to service the older DOT
specification cylinders and the new metric-marked cylinders, or (2)
continue to maintain its currently installed hydrostatic test equipment
and service only the older DOT specification cylinders (estimated to
now number 300 million, a majority of which may be expected to remain
in service well into the next century) and the proposed DOT-4M metric-
marked cylinder that have a marked test pressure of 70 bar.
RSPA anticipates that some small entities currently performing
requalification functions by the hydrostatic pressure test method may
determine that investments in new ultrasonic test equipment (requiring
an investment currently estimated at $50-$80 thousand amortized over a
period of ten (10) years) may not be economically feasible, considering
the comparatively small number of metric-marked cylinders (vs. the
current size of the domestic fleet of approximately 300
[[Page 58475]]
million cylinders) that will be produced beginning perhaps as early as
1999, and first requiring periodic requalification in 2004. Currently,
five (5) of the eighteen (18) retester facilities currently performing
requalification of cylinders by ultrasonic examination, rather than by
hydrostatic pressure testing, under terms of special exemptions issued
by RSPA are thought to meet the criterion for a small business.
Although the ultrasonic examination method initially involves a
large capital investment, it offers cost savings for businesses that
own and/or use cylinders for the transportation of compressed gases. In
addition, ultrasonic examination provides (1) substantial benefits for
increased safety, (2) opportunities for reducing emissions of hazardous
materials to the environment, and (3) reduced contamination of
cylinders.
Commenters are specifically invited to provide additional
information with respect to this proposed requirement for ultrasonic
testing of metric-marked cylinders and its potential impact on small
entities. RSPA requests comments from affected small entities regarding
the potential adverse impact this proposed rule may have on their
cylinder requalification operations specifically, and the overall
viability of their enterprise should they determine it would be
economically prohibitive to continue to perform cylinder
requalification services.
3. Finally, there are literally hundreds of thousands of commercial
establishments that own and use cylinders manufactured to
specifications in the DOT-3 and DOT-4 series. Those business sectors
include agriculture; mining; construction; manufacturing;
transportation, communications, electric, gas and sanitary services;
wholesale trade; retail trade; services; and many other nonclassifiable
establishments. On the basis of a Small Business Administration
estimate that of the 24 million businesses located in the U.S. only
15,000 (.000625%) are large firms, RSPA concedes it is likely that over
99% of the businesses that make use of compressed gases in DOT
specification cylinders are small businesses. (Source: SBA Office of
Advocacy, Small Business Answer Card 1998).
RSPA believes the proposed rules will generally have a small
individual, though significant in the aggregate (i.e., $10 million
annually), positive benefit for all of these businesses by making the
metric-marked cylinders they buy or lease acceptable for trade and use
in worldwide commerce. In addition, those cylinders will be allowed to
be charged with a wider range of compressed gases and other materials,
and, in many cases, the period between periodic requalification will be
extended by several years, thereby resulting in cost savings attributed
to less frequent inspections. For example, in the case of a
specification DOT-3AL aluminum cylinder, the 5 year retest cycle would
be extended to 10 years for the specification DOT-3ALM. In time, there
may be as many as 1 million such cylinders in carbon dioxide service
for the carbonated beverage industry alone. A single retest of this
fleet of cylinders over a ten-year period vs. the current five-year
period, at an average cost of $10 per cylinder, i.e., $10 million,
would result in aggregate savings to the cylinder owners of $1 million
per year. In the very competitive soft-drink industry, RSPA believes
that the cost savings would be shared broadly.
To the extent that RSPA has failed to recognize potential impacts
on the general universe of small entities that own or use cylinders,
commenters are invited to identify those impacts and the magnitude of
their affect on small entities.
Reporting and recordkeeping requirements. This proposed rule
contains one new requirement for reporting and recordkeeping.
Specifically, persons who requalify cylinders by a visual inspection,
as currently authorized by Sec. 173.34(e)(13), would, under proposed
Sec. 180.209(g), be required to first obtain a requalification
identification number (RIN) from RSPA's Associate Administrator for
Hazardous Materials Safety under provisions of proposed Sec. 107.805.
Essential elements of the application for approval include: (1) the
name and address of the facility manager, (2) identification of the DOT
specification/exemption cylinders that will be inspected at the
facility, and (3) a signed and dated certification by the applicant
that the facility will operate in compliance with applicable
requirements of the HMR, and that the hazmat employees performing
inspections have been properly trained, to include familiarization with
the appropriate CGA C-6 series pamphlets concerning the conduct of
visual inspections.
An approval, if issued by the Associate Administrator for Hazardous
Materials Safety, would be effective for a maximum of five years, at
which time the approval holder would have to file a new application for
approval. Other than the requirements for having to file an application
for approval, and entering the four-digit RIN (in addition to the
month, year and letter ``E'' currently required) on each cylinder
requalified by the visual inspection method, there is no additional
regulatory burden associated with this proposal.
While the actual number of facilities currently operating under the
exception provided by Sec. 173.34(e)(13) is unknown, RSPA assumes, on
the basis of data compiled by the Bureau of the Census, that the actual
number is not more than 6,691, of which 5,651 are retail dealers of
bottled liquefied petroleum gases (SIC Code 5984), 968 are merchant
wholesalers of industrial gases, except liquefied petroleum gases (SIC
Code 5169), and 72 are entities identified as EPA-approved reclaimers
of refrigerant gases.
On a per facility basis, RSPA estimates the cost of this reporting
and recordkeeping requirement would be $122.50 per five-year cycle.
This estimate was calculated on the basis of cost data submitted by
RSPA to the Office of Management and Budget in support of an approval
issued by OMB (2137-0022) concerning Testing, Inspection and Marking
Requirements for Cylinders. RSPA does not see this proposed regulatory
requirement as inhibiting the ability of currently excepted retesters
to continue to provide this cylinder requalification service to an
extent that it threatens the viability of their primary business, i.e.,
the sale of compressed gases in relatively small units. RSPA
specifically invites commenters to provide data that supports or
refutes this estimate of the costs of compliance with the new
requirement to obtain a retester (requalification) identification
number and its impact on small businesses currently authorized to
perform this requalification function without first having to obtain an
approval from the Associate Administrator for Hazardous Materials
Safety.
Related Federal rules and regulations. With respect to the
production, permitted use, and periodic requalification of cylinders
used in the transportation in commerce of compressed gases, there are
no related rules and regulations issued by other departments or
agencies of the Federal government.
Alternate proposals for small businesses. The Regulatory
Flexibility Act directs agencies to establish exceptions and differing
compliance standards, when possible, for small business, while still
meeting objectives of the applicable regulatory statutes. In the case
of manufacture, use, inspection, testing, retesting and requalification
of DOT specification cylinders in compressed gas service, RSPA believes
[[Page 58476]]
that it is not possible to establish such differing standards and still
accomplish the objectives of Federal hazardous materials transportation
law (49 U.S.C. 5101-5127). RSPA further believes that the discussion in
this NPRM as to the need for regulatory action, issues raised by many
of the affected parties through petitions for rulemaking, applications
for exemption, and otherwise, effectively requires RSPA to apply one
set of requirements applicable to small and large businesses alike.
While certain regulatory actions may affect the competitive
situation of an industry by imposing relatively greater burdens on
small-scale than on large-scale enterprises, RSPA does not believe that
this will be the case with the proposed rule. The principal types of
compliance expenditure effectively required by the proposed rule would
be imposed on each cylinder represented through its specification
markings as conforming to a DOT specification, whether manufactured by,
used by, or serviced by a large or a small business. There are
administrative efficiency advantages, and economies of scale, available
to a large firm, but the requirements considered in this rulemaking are
intended to assure a minimum level of safety for packagings used to
contain hazardous materials that pose high-order risks in
transportation. Thus, no provisions may be waived simply on the basis
that they would be burdensome to a small business.
At the same time, RSPA notes that the proposed rules were developed
under the assumption that small businesses comprise an overwhelming
majority of entities that would be compelled to comply, particularly
regarding permitted use of cylinders and their periodic requalification
for continued use. For that reason, in its development of the proposed
rules, RSPA considered each requirement and determined this set
represents the minimal requirements necessary for it to be able to
assure an adequate level of safety in transportation.
For example, as an accommodation to small businesses, RSPA proposes
to (1) permit facilities to continue to use their currently installed
hydrostatic pressure test equipment to retest non-metric marked
specification cylinders, millions of which have been in service for
several decades and may be expected to continue in service for many
more decades, and (2) permit the requalification of certain metric-
marked cylinders, i.e., specification DOT-4M with a marked test
pressure 70 bar.
Section 610 Review
Pursuant to section 610 of the Regulatory Flexibility Act (5 U.S.C.
Sec. 610), RSPA has conducted a review of current requirements for the
manufacture, use, and requalification of cylinders. The purpose of this
review was to identify regulations that have a significant economic
impact on a substantial number of small entities and to revise those
regulations, where appropriate. In proposing revisions to the existing
regulations, RSPA has attempted to minimize the economic impact on
small business entities. It has done this, in part, by proposing to
reduce from fifteen to four the number of authorized DOT-3 and DOT-4
series cylinder specifications, allowing greater fill limits for
metric-marked cylinders, and extending the time between periodic
requalification of metric-marked cylinders. Also, small business, such
as boiler shops (SIC 3443), iron and steel forging shops (SIC 3462),
merchant wholesalers of industrial gases, except liquefied petroleum
gas (LPG) (SIC 5169), retail dealers of LPG (SIC 5984), and business
services, not elsewhere classified (SIC 7389), will benefit from the
greater safety provided by this proposed rule. RSPA encourages small
entities to comment on the economic impact of proposals contained in
this NPRM.
First, RSPA examined whether there is a continuing need for its
cylinder regulations. Based on the various characteristics of
compressed gases (e.g., flammability and toxicity) and the associated
risks that are involved in the transportation of gases, RSPA recognizes
that there is a continuing need for its cylinder regulations. However,
as discussed previously in this preamble, RSPA is in receipt of
numerous petitions for rulemaking concerning the cylinder regulations.
Many of these petitions propose that RSPA incorporate accepted industry
practices and new technology (e.g., new marking methods). RSPA has
accepted many of these petitions and is proposing to incorporate new
technology where the new technology achieves an equivalent or higher
level of safety (e.g., ultrasonic testing). RSPA also reviewed
exemptions issued under 49 CFR Part 107 and has incorporated those
exemption provisions that have achieved a proven safety record.
In addition to the above, over the years, the regulated community
has requested that RSPA reduce the complexity of its cylinder
regulations. RSPA addressed these concerns by modifying the language
used in the proposed rule, including a definition section and changing
the organizational structure of the cylinder regulations. RSPA also
recognizes that market conditions have changed dramatically since many
of the existing rules were first adopted. Today, cylinders are
manufactured, used, and transported to, from, and between entities in
the global marketplace. In recognition of that worldwide sale and
distribution of compressed gases in cylinders, RSPA is proposing to
revise the HMR in a manner that is harmonious with international
standards (e.g., metric-marked cylinders).
RSPA is confident that the proposed rule and existing cylinder
regulations do not duplicate or conflict with other Federal rules. In
addition, conflicts with state or local regulations are expressly
provided for in Federal hazardous materials transportation law (49
U.S.C. Sec. 5125). Under this statutory authority, RSPA issues
preemption determinations as to whether a State, political subdivision,
or Indian tribe regulation or law, governing the transportation of
hazardous materials, is preempted under Federal law (see 49 C.F.R. Part
107, Subpart C).
C. Executive Orders 12612 and 13084
This proposed rule has been analyzed in accordance with the
principles and criteria contained in Executive Orders 12612
(``Federalism'') and 13084 (``Consultation and Coordination with Indian
Tribal Governments''). Because this proposed regulation would have no
substantial direct effect on the States or the relationship, or the
distribution of power and responsibilities, between the Federal
Government and the States, RSPA has determined that this rule does not
have sufficient federalism implications to warrant preparation of a
Federalism Assessment. Because this rule would not significantly or
uniquely affect the communities of the Indian tribal governments, the
funding and consultation requirements of Executive Order 13084 do not
apply.
Federal hazardous material transportation law contains express
preemption provisions at 49 U.S.C. 5125 that preempt State, local, and
Indian tribe requirements if----
(1) Complying with a requirement of the State, political
subdivision, or Indian tribe and Federal hazardous material
transportation law or regulations is not possible;
(2) The requirement of the State, political subdivision, or Indian
tribe, as applied or enforced, is an obstacle to accomplishing and
carrying out Federal hazardous material transportation law or
regulations; or
[[Page 58477]]
(3) The requirement of the State, political subdivision, or Indian
tribe concerns any of the following ``covered subjects'' and is not
substantially the same as a provision of Federal hazardous material
transportation law or regulations:
(A) The designation, description, and classification of hazardous
material;
(B) The packing, repacking, handling, labeling, marking, and
placarding of hazardous material;
(C) The preparation, execution, and use of shipping documents
related to hazardous material and requirements related to the number,
contents, and placement of those documents;
(D) The written notification, recording, and reporting of the
unintentional release in transportation of hazardous material; and
(E) The design, manufacture, fabricating, marking, maintenance,
reconditioning, repairing, or testing of a packaging or container
represented, marked, certified, or sold as qualified for use in
transporting hazardous material.
This proposed rule concerns the packing and handling of hazardous
materials, and the design, manufacture, fabrication, marking,
maintenance, and testing of cylinders that are marked and certified as
qualified for use in the transportation of hazardous materials. If so
adopted as final, this rule would preempt any State, local, or Indian
tribe requirements concerning these subjects unless the non-Federal
requirements are ``substantially the same'' (see 49 CFR 107.202(d)) as
the Federal requirements.
Federal law (49 U.S.C. 5125(b)(2)) provides that if DOT issues a
regulation concerning any of the covered subjects, DOT must determine
and publish in the Federal Register the effective date of Federal
preemption. The effective date may not be earlier than the 90th day
following the date of issuance of the final rule and not later than two
years after the date of issuance.
RSPA requests comments on what the effective date of the Federal
preemption should be for the requirements in this proposed rule that
concern covered subjects.
D. Unfunded Mandates Reform Act of 1995
This proposed rule would not impose unfunded mandates under the
Unfunded Mandates Reform Act of 1995. It does not result in costs of
$100 million or more, in the aggregate, to any of the following: State,
local, or Indian tribal governments, or the private sector. This rule
is the least burdensome alternative that achieves the objective of the
rule.
E. Paperwork Reduction Act
Under regulations implementing the Paperwork Reduction Act of 1995,
`` * * * an agency may not conduct or sponsor, and a person is not
required to respond to a collection of information unless it displays a
valid OMB control number.'' 5 CFR 1320.8(b)(iii)(6).
The information collection and recordkeeping requirements in
current Secs. 173.34, 173.302(c) and 178.35 pertaining to records
prepared by persons performing the requalification, repair, rebuild and
use of cylinders and requirements in current Sec. 173.34 pertaining to
persons seeking approval to requalify cylinders, were approved by the
Office of Management and Budget (OMB) under the provisions of 44 U.S.C.
chapter 35 and assigned control number 2137-0022, with an expiration
date of August 31, 1999. This information is used to verify that
cylinders meet the required manufacturing standards prior to being
authorized for initial use, and that once manufactured, the cylinders
are maintained and used in compliance with applicable requirements of
the HMR as packagings for hazardous materials. In this proposed rule,
these information collection and recordkeeping requirements for records
are revised and are in Secs. 178.35, 178.69(e)(13), 180.205, 180.209,
180.211, 180.213, and 180.215.
The information and recordkeeping requirements in current
Secs. 173.300a and 173.300b for persons seeking approval to be an
independent inspection agency, and for chemical analyses and tests of
DOT specification and exemption cylinders conducted outside of the
United States, were approved by OMB and assigned control number 2137-
0557, with an expiration date of July 31, 1999. The information is used
to evaluate an applicant's qualification to perform the applicable
packaging functions and to ensure material of construction used in
cylinders made outside the United States are in accordance with the
applicable requirements. In this proposed rule, the information
collection and recordkeeping requirements are in Secs. 107.803,
107.805, 107.807 and 180.205(c). The information collection and
recordkeeping requirements for persons seeking approval as cylinder
requalifiers and approval to change a cylinder's service pressure are
removed from OMB control number 2137-0022 and being placed with the
other approval requirements under OMB control number 2137-0557. OMB
control number 2137-0557 includes information and recordkeeping
requirements for other than cylinders. The estimates contained in this
proposed rule address only the cylinder provisions.
Because this proposed rule would establish certain new cylinder
specifications, broaden the approval requirements for affected persons
who requalify cylinders, and would relocate the cylinder
requalification requirements to other sections, revisions would be made
to the current burden hour submission. RSPA has revised the burden
estimates based on the proposal in this NPRM and will submit revised
burden estimates to OMB.
OMB Control Number 2137-0022
Affected Public: Cylinder requalifiers, repairers and rebuilders,
and owners of certain DOT specification and exemption cylinders.
Annual Reporting and Recordkeeping Burden:
Number of Respondents: 500.
Total Annual Responses: 5,000.
Total Annual Burden Hours: 1,729.
Total Annual Cost for Development and Maintenance: $42,683.
OMB Control Number 2137-0557
Affected Public: Cylinder manufacturers, requalifiers, and persons
seeking to change a cylinder's service pressure.
Annual Reporting and Recordkeeping Burden:
Number of Respondents: 2,027.
Total Annual Responses: 2,027.
Total Annual Burden Hours: 2,628.
Total Annual Cost for Development and Maintenance: $294,544.
RSPA invites comments on these revised information collection
estimates, including any paperwork burdens not already considered.
Requests for a copy of these information collections should be directed
to Deborah Boothe, Office of Hazardous Materials Standards, Room 8102,
400 Seventh Street, SW, Washington, DC 20590-0001. Telephone (202) 366-
8553 or 1-800-467-4922. Written comments should be received by the
close of the comment period indentified in the DATES section of this
rulemaking and should be addressed to the Dockets Management System as
identified in the ADDRESSES section of this rulemaking. Comments must
reference the docket number, RSPA 98-3684 (HM-220).
F. Regulation Identifier Number (RIN)
A regulation identifier number (RIN) is assigned to each regulatory
action listed in the Unified Agenda of Federal Regulations. The
Regulatory Information Service Center publishes the Unified Agenda in
April and October of each year. The RIN contained in the heading
[[Page 58478]]
of this document can be used to cross-reference this action with the
Unified Agenda.
List of Subjects
49 CFR Part 107
Administrative practice and procedure, Hazardous materials
transportation, Packaging and containers, Penalties, Reporting and
recordkeeping requirements.
49 CFR Part 171
Exports, Hazardous materials transportation, Hazardous waste,
Imports, Incorporation by reference, Reporting and recordkeeping
requirements.
49 CFR Part 172
Hazardous materials transportation, Hazardous waste, Labeling,
Packaging and containers, Reporting and recordkeeping requirements.
49 CFR Part 173
Hazardous materials transportation, Packaging and containers,
Radioactive materials, Reporting and recordkeeping requirements,
Uranium.
49 CFR Part 177
Hazardous materials transportation, Motor vehicle safety, Packaging
and containers, Reporting and recordkeeping requirements.
49 CFR Part 178
Hazardous materials transportation, Packaging and containers,
Reporting and recordkeeping requirements.
49 CFR Part 180
Hazardous materials transportation, Motor vehicle safety, Packaging
and containers, Reporting and recordkeeping requirements.
In consideration of the foregoing, title 49, Chapter I, Subchapters
A and C of the Code of Federal Regulations, are proposed to be amended
as follows:
PART 107--HAZARDOUS MATERIALS PROGRAM PROCEDURES
1. The authority citation for Part 107 would continue to read as
follows:
Authority: 49 U.S.C. 5101-5127, 44701; Sec. 212-213, Pub. L.
104-121, 110 Stat. 857; 49 CFR 1.45, 1.53.
Sec. 107.3 [Amended]
2. In Sec. 107.3, the definition of ``Registration'' would be
amended by removing the wording ``registration with RSPA as a cylinder
retester pursuant to 49 CFR 173.34(e)(1), or''.
3. Subpart I would be added to Part 107 to read as follows:
Subpart I--Approval of Independent Inspection Agencies, Cylinder
Requalifiers, and Non-domestic Chemical Analyses and Tests of DOT
Specification Cylinders
Sec.
107.801 Purpose and Scope.
107.803 Approval of independent inspection agency.
107.805 Approval of cylinder requalifiers.
107.807 Approval of non-domestic chemical analyses and tests.
Subpart I--Approval of Independent Inspection Agencies, Cylinder
Requalifiers, and Non-domestic Chemical Analyses and Tests of DOT
Specification Cylinders
Sec. 107.801 Purpose and scope.
(a) This subpart prescribes procedures for--
(1) A person who seeks approval to be an independent inspection
agency to perform cylinder inspections and verifications required by
parts 178 and 180 of this chapter;
(2) A person who seeks approval to engage in the requalification
(i.e., inspection, testing or certification), rebuild or repair of a
cylinder manufactured in accordance with a DOT specification under
subchapter C of this chapter or under the terms of an exemption issued
under this part;
(3) A person who seeks approval to perform the manufacturing
chemical analyses and tests of DOT specification or exemption cylinders
outside the United States.
(b) No person may engage in a function identified in paragraph (a)
of this section unless approved by the Associate Administrator in
accordance with the provisions of this subpart. Each person shall
comply with the applicable requirements in this subpart. In addition,
the procedural requirements in subpart H of this part apply to the
filing, processing and termination of an approval issued under this
subpart.
Sec. 107.803 Approval of independent inspection agency.
(a) General. Prior to performing cylinder inspections and
verifications required by parts 178 and 180 of this chapter, a person
must apply to the Associate Administrator for an approval as an
independent inspection agency. A person approved as an independent
inspection agency is not a RSPA agent or representative.
(b) Criteria. No applicant for approval as an independent
inspection agency may be engaged in the manufacture of cylinders for
use in the transportation of hazardous materials, or be directly or
indirectly controlled by, or have a financial involvement with, any
entity that manufactures cylinders for use in the transportation of
hazardous materials, except for providing services as an independent
inspector.
(c) Application information. Each applicant must submit an
application in conformance with Sec. 107.705 that must contain the
information prescribed in Sec. 107.705(a). In addition, the application
must contain the following information:
(1) Name and address of each manufacturing facility where tests and
inspections are to be performed and a detailed description of the
inspection and testing facilities to be used by the applicant and the
applicant's ability to perform the inspections and to verify the
inspections required by part 178 of this chapter or under the terms of
an exemption issued under this part.
(2) Name, address, and principal business activity of each person
having any direct or indirect ownership interest in the applicant
greater than three percent and any direct or indirect ownership
interest in each subsidiary or division of the applicant.
(3) Name of each individual whom the applicant proposes to employ
as an inspector and will be responsible for certifying inspection and
test results and a statement of that person's qualifications.
(4) An identification or qualification number assigned to each
inspector who is supervised by a certifying inspector identified in
(c)(3) of this section.
(5) A statement that the applicant will perform its functions
independent of the manufacturers and owners of the cylinders.
(6) If the applicant's principal place of business is in a country
other than the United States--
(i) A copy of the designation from the Competent Authority of that
country delegating to the applicant an approval or designated agency
authority for the type of packaging for which a DOT designation is
sought; and
(ii) A statement from the Competent Authority of that country
stating that similar authority is delegated to other Independent
Inspection Agencies who are approved under this subpart and that no
condition or limitation will be imposed upon United States citizens or
organizations that is not required of its own citizenry.
(7) The date and signature of the person certifying the approval
application
(d) Facility inspection. Upon the request of the Associate
Administrator, the applicant shall allow the Associate Administrator or
the Associate Administrator's designee to inspect the applicant's
facilities and records. The person seeking approval must bear the cost
of RSPA's inspection.
[[Page 58479]]
Sec. 107.805 Approval of cylinder requalifiers.
(a) General. A person must meet the requirements of this section to
be approved to inspect, test, certify, repair, or rebuild a cylinder in
accordance with a DOT specification under subpart C of part 178 or
subpart C of part 180 of this chapter or under the terms of an
exemption issued under this part.
(b) Each applicant must arrange for an independent inspection
agency, approved by the Associate Administrator pursuant to this
subpart, to perform a review of its inspection or requalification
operation. The person seeking approval must bear the cost of the
inspection. A list of approved independent inspection agencies is
available from the Associate Administrator at the address listed in
Sec. 107.705. Assistance in obtaining an approval may be requested from
the same address.
(c) Application for approval. If the inspection performed by an
independent inspection agency is completed with satisfactory results,
the applicant must submit a letter of recommendation from the
independent inspection agency, an inspection report, and an application
that must contain the information prescribed in Sec. 107.705(a). In
addition, the application must contain the following information: the
name of the facility manager; the DOT specification/exemption cylinders
that will be inspected, tested, repaired, or rebuilt at the facility; a
certification that the facility will operate in compliance with the
applicable requirements of subchapter C of this chapter; and the date
and the signature of the person making the certification.
(d) Issuance of requalifier identification number (RIN). The
Associate Administrator issues a RIN as evidence of approval to
requalify DOT specification/exemption cylinders if it is determined,
based on the applicant's submission and other available information,
that the applicant's qualifications and, when applicable, facility are
adequate to perform the requested functions in accordance with the
criteria prescribed in subpart C of part 180 of this chapter.
(e) Expiration of RIN. Unless otherwise provided in the issuance
letter, an approval expires five years from the date of issuance,
provided that the applicant's facility and qualifications are
maintained at or above the level observed at the time of inspection by
the independent inspection agency, or at the date of the certification
in the application for approval, for facilities only performing
inspections made under Sec. 180.209(g) of this chapter.
(f) Exceptions. Notwithstanding requirements in paragraphs (b) and
(c) of this section, a person who only performs inspections in
accordance with Sec. 180.209(g) of this chapter must submit a request
which, in addition to the information prescribed in Sec. 107.705(a)
contains; the facility manager for each location in which
requalifications would be performed; the DOT specification/exemption
cylinders that will be inspected at the facility; a certification that
the facility will operate in compliance with the applicable
requirements of subchapter C of this chapter; a certification that the
persons performing inspections have been trained and have the
information contained in each applicable CGA pamphlet incorporated by
reference in Sec. 171.7 of this chapter that applies to the
requalifiers activities; and the date and the signature of the person
making the certification. Each person shall comply with the applicable
requirements in this subpart. In addition, the procedural requirements
in subpart H of this part apply to the filing, processing and
termination of an approval issued under this subpart.
Sec. 107.807 Approval of non-domestic chemical analyses and tests.
(a) General. A person who seeks to manufacture DOT specification or
exemption cylinders outside the United States must seek an approval
from the Associate Administrator to perform the chemical analyses and
tests of those cylinders outside the United States.
(b) Application for approval. Each applicant must submit an
application that must contain the information prescribed in
Sec. 107.705(a). In addition, the application must contain the
following information: the name, address and a description of each
facility at which cylinders are to be manufactured and chemical
analyses and tests are to be performed; complete details concerning the
dimension, materials of construction, wall thickness, water capacity,
shape, type of joints, location and size of openings and other
pertinent physical characteristics of each specification or exemption
cylinder for which approval is being requested, including calculations
for cylinder wall stress and wall thickness which may be shown on a
drawing or on separate sheets attached to a descriptive drawing; the
name of the independent inspection agency to be used; and the date and
the signature of the person making the certification.
(c) Facility inspections. Upon the request of the Associate
Administrator, the applicant shall allow the Associate Administrator
for HMS or the Associate Administrator's designee to inspect the
applicant's cylinder manufacturing and testing facilities and records,
and must provide such materials and cylinders for analyses and tests as
the Associate Administrator may specify. The applicant or holder shall
bear the cost of the initial and subsequent inspections, analyses, and
tests.
PART 171--GENERAL INFORMATION, REGULATIONS, AND DEFINITIONS
4. The authority citation for part 171 would continue to read as
follows:
Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.
Sec. 171.2 [Amended]
5. In Sec. 171.2, paragraph (d)(3) would be amended by removing the
wording ``retest or exemption markings'' and adding in its place the
wording ``retest, exemption or requalification identification number
(RIN) markings''.
6. In Sec. 171.7, in the table in paragraph (a)(3), new entries
would be added in alphanumeric sequence to read as follows:
Sec. 171.7 Reference material.
(a) * * *
(3) Table of material incorporated by reference. * * *
------------------------------------------------------------------------
Source and name of material 49 CFR reference
------------------------------------------------------------------------
* * * *
* * *
American Society for Nondestructive Testing,
PO Box 28518, 1711 Arlingate Lane, Columbus,
OH 43228-0518
ASNT Recommended Practice SNT-TC-1A, 1992 Part 178, subpart C,
Appendix B.
* * * *
* * *
American Society for Testing and Materials
[[Page 58480]]
* * * *
* * *
ASTM B 221-96 Standard Specification for 178.46(a)(4), Table 2.
Aluminum and Aluminum-Alloy Extruded
Bars, Rods, Wire, Profiles, and Tubes.
ASTM B 221M-96 Standard Specification for Part 178, Subpart C,
Aluminum and Aluminum-Alloy Extruded Appendix A, Table 2,
Bars, Rods, Wire, Profiles, and Tubes. Aluminum.
* * * *
* * *
ASTM E 10-96 Standard Test Method for 178.69.
Brinell Hardness of Metallic Materials.
ASTM E 18-94 Standard Test Methods for 178.70.
Rockwell Hardness and Rockwell
Superficial Hardness of Metallic
Materials.
* * * *
* * *
ASTM E 165-95 Standard Test Method for 178.69.
Liquid Penetrant Examination.
ASTM E 213-93 Standard Practice for 178.71; 178.72; 178.73;
Ultrasonic Examination of Metal Pipe and Part 178, Subpart C,
Tubing. Appendix B; 180.215.
* * * *
* * *
ASTM E 399-90e1 Standard Test Method for 178.73.
Plane-Strain Fracture Toughness of
Metallic Materials.
* * * *
* * *
ASTM E 709-95 Standard Guide for Magnetic 178.69.
Particle Examination.
ASTM E 797-95 Standard Practice for Part 178, Subpart C,
Measuring Thickness by Manual Ultrasonic Appendix B; 180.215.
Pulse-Echo Straight-Beam Method.
* * * *
* * *
Compressed Gas Association, Inc.
* * * *
* * *
CGA Pamphlet C-1, Methods for Hydrostatic 178.69; 178.81; 180.205.
Testing of Compressed Gas Cylinders,
1996.
* * * *
* * *
CGA Pamphlet P-20, Standard for the 173.115.
Classification of Toxic Gas Mixtures,
1995.
* * * *
* * *
CGA Pamphlet S-7, Method for Selecting 173.301.
Pressure Relief Devices for Compressed
Gas Mixtures in Cylinders, 1996.
* * * *
* * *
------------------------------------------------------------------------
Sec. 171.7 [Amended]
7. In addition, in Sec. 171.7, in the table in paragraph (a)(3),
the following changes would be made:
a. In the entry ASTM A240/A240M-94b, the wording ``A240M-94b''
would be revised to read ``A240M-96a.''
b. The entry ASTM A 388-67 would be removed.
c. In the entry ASTM B 557-84, in column 2, the reference
``178.69;'' would be added, in numeric order.
d. In the entry ASTM E 8-89, the wording ``E 8-89'' would be
revised to read ``E 8-96a'' and in column 2, the references ``178.36;
178.37; 178.38; 178.39;'', ``178.45;'', ``178.50; 178.51;'',
``178.55;'', ``178.61;'', and ``178.68;'' would be removed and
``178.69;'' would be added, in numerical order.
e. In the entry ASTM E 23-60, in column 1, the wording ``E 23-60''
would be revised to read ``E 23-96'' and in column 2, the reference
``178.69;'' would be added, in numeric order.
f. In the entry ASTM E 112-88, the wording ``E 112-88'' would be
revised to read ``E 112-96'' and in column 2, the reference ``;178.69''
would be added, in numeric order.
g. In the entry ASTM E 290-92, in column 2, the references
``;178.69; 178.72'' would be added, in numeric order.
h. In the entry CGA Pamphlet C-3, the year ``1975'' would be
revised to read ``1994'' and in column 2, the references ``178.50;
178.51;'', ``178.54;'', ``178.61;'', ``178.68'' would be removed and
``178.69;'', ``178.81;'', ``180.211'' would be added, in numeric order.
i. In the entry CGA Pamphlet C-5, in column 2, the reference
``173.302'' would be removed and ``173.302a'' would be added, in its
place.
j. In the entry CGA Pamphlet C-6, in column 2, the reference
``173.34; 180.519'' would be removed and the references ``173.198;
180.205; 180.209; 180.211.'' would be added, in its place.
k. In the entry CGA Pamphlet C-6.1, in column 2, the reference
``173.34'' would be removed and the references ``180.205; 180.209''
would be added, in its place.
l. In the entry CGA Pamphlet C-6.2, in column 2, the reference
``173.34'' would be removed and the reference ``180.205'' would be
added, in its place.
m. In the entry CGA Pamphlet C-6.3, in column 2, the reference
``173.34'' would be removed and the references ``180.205; 180.209''
would be added, in its place.
n. In the entry CGA Pamphlet C-8, in column 2, the reference
``173.34'' would be removed and the reference ``180.205'' would be
added, in its place.
o. In the entry CGA Pamphlet C-11, in column 2, the reference
``178.35'' would be removed and the references ``178.35; 178.69'' would
be added, in its place.
p. In the entry CGA Pamphlet C-12, in column 2, the reference
``173.34;'' would be removed and the references 173.301;'' and
``;180.205'' would be added, in numeric order.
q. In the entry CGA Pamphlet C-13, in column 2, the reference
``173.34;'' would be removed and the references ``; 180.205;'', and
``180.209.'' would be added, in numeric order.
r. In the entry CGA Pamphlet C-14, in column 2, the reference
``173.34'' would
[[Page 58481]]
be removed and the reference ``173.301'' would be added, in its place.
s. In the entry CGA Pamphlet S-1.1, in column 2, the reference
``173.34'' would be removed and the references ``173.301; 173.304a.''
would be added, in its place.
8. In Sec. 171.8, definitions for ``Metric-marked cylinder'' and
``Nonmetric-marked cylinder'' would be added, in alphabetical order, to
read as follows:
Sec. 171.8 Definitions and abbreviations.
* * * * *
Metric-marked cylinder means a cylinder manufactured to the DOT 3M,
3ALM, 3FM or 4M specification prescribed in Secs. 178.69 through 178.81
of this subchapter.
* * * * *
Nonmetric-marked cylinder means a cylinder manufactured to a DOT
specification prescribed in Secs. 178.35 through 178.68 of this
subchapter that was in effect on [DATE PRIOR TO EFFECTIVE DATE OF THE
FINAL RULE].
* * * * *
Sec. 171.8 [Amended]
9. In addition, in Sec. 171.8, in the definition of ``Filling
density'', paragraph (1) would be amended by revising the reference
``Sec. 173.304(a)(2)Table Note 1'' to read ``Sec. 173.304a(a)(2) Table
Note 1''.
10. In Sec. 171.12, paragraph (b)(15) would be revised to read as
follows:
Sec. 171.12 Import and export shipments.
* * * * *
(b) * * *
(15) Cylinders not manufactured to a DOT specification must conform
to the requirements of Sec. 173.301(j) through (l) of this subchapter
or, for Canadian manufactured cylinders, to the requirements of
Sec. 171.12a(b)(13).
* * * * *
11. In Sec. 171.12a, in paragraph (b)(13) a new sentence would be
added at the end of the paragraph, and paragraphs (b)(13)(i) through
(b)(13)(v) would be added to read as follows:
Sec. 171.12a Canadian shipments and packagings.
* * * * *
(b) * * *
(13) * * * However, a cylinder made in Canada that meets the
following conditions is authorized for the transportation of a
hazardous material within the United States:
(i) The cylinder was manufactured on or after January 1, 1977;
(ii) During the manufacturing process, the cylinder was marked with
an approval number and an inspector's mark authorized by TDG or by its
predecessor, the Railway Transport Committee of the Canadian Transport
Commission (CTC), in its regulations for the Transport of Dangerous
Commodities by Rail and was marked ``CTC'' or ``TDG'';
(iii) The cylinder is in full conformance with the specifications
prescribed by the TDG regulations;
(iv) The cylinder has been requalified under a program authorized
by the Canadian regulations or requalified in accordance with subpart C
of part 180 of this subchapter within the prescribed requalification
period; and
(v) At the time the requalification is performed, in addition to
the markings prescribed in Sec. 180.211 of this subchapter, the
cylinder is marked ``DOT/'' immediately before the Canadian
specification marking.
* * * * *
PART 172--HAZARDOUS MATERIALS TABLE, SPECIAL PROVISIONS, HAZARDOUS
MATERIALS COMMUNICATIONS, EMERGENCY RESPONSE INFORMATION, AND
TRAINING REQUIREMENTS
12. The authority citation for Part 172 would continue to read as
follows:
Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.
Sec. 172.101 [Amended]
13. Section 172.101, in the Hazardous Materials Table, the
following changes would be made:
a. For the entry ``Cyanogen'', in Column (8b), the reference
``192'' would be removed and ``304'' would be added in its place.
b. For the entry ``Germane'', in Column (8b), the reference ``192''
would be removed and ``302'' would be added in its place.
c. For the entry ``Iron pentacarbonyl'', in Column (8b), the
reference ``192'' would be removed and ``226'' would be added in its
place.
PART 173--SHIPPERS--GENERAL REQUIREMENTS FOR SHIPMENTS AND
PACKAGINGS
14. The authority citation for Part 173 would continue to read as
follows:
Authority: 49 U.S.C. 5101-5127, 44701; 49 CFR 1.45, 1.53.
Sec. 173.34 [Removed]
15. Section 173.34 would be removed.
16. Section 173.40 would be revised to read as follows:
Sec. 173.40 General packaging requirements for toxic materials
packaged in cylinders.
When this section is referenced for a hazardous material elsewhere
in this subchapter, the following requirements are applicable to
cylinders used for that material:
(a) Authorized cylinders. A cylinder must conform to one of the
specifications for cylinders in subpart C of part 178 of this
subchapter, except that Specification 8, 8AL, and 39 cylinders are not
authorized. After [EFFECTIVE DATE OF THE FINAL RULE] DOT 3AL cylinders
made of aluminum alloy 6351 may not be filled and offered for
transportation or transported with a Division 2.3, Zone A or B
material, a Division 6.1, Zone A or B material or any liquid that meets
the definition of Division 6.1 and meets criteria for Packing Group I,
Hazard Zones A or B, as specified in Sec. 173.133.
(b) Closures. Each cylinder containing a Hazard Zone A material
must be closed with a plug or valve conforming to the following:
(1) Each plug or valve must have a taper-threaded connection
directly to the cylinder and be capable of withstanding the test
pressure of the cylinder;
(2) Each valve must be of the packless type with non-perforated
diaphragm, except that for corrosive materials, a valve may be of the
packed type provided the assembly is made gas-tight by means of a seal
cap with gasketed joint attached to the valve body or the cylinder to
prevent loss of material through or past the packing;
(3) Each valve outlet must be sealed by a threaded cap or threaded
solid plug; and
(4) Cylinder, valves, plugs, outlet caps, luting and gaskets must
be compatible with each other and with the lading.
(c) Additional handling protection. Each cylinder or cylinder
overpack combination offered for transportation containing a Division
2.3 or 6.1 Hazard Zone A or B material must meet the puncture
resistance and valve damage protection performance requirements of this
section. In addition to the requirements of this section, overpacks
must conform to the overpack provisions of Sec. 173.25.
(1) Puncture resistance. Each cylinder or cylinder overpack
combination must be qualified under the puncture resistance test
specified in Sec. 178.69(h)(3) of this subchapter. However, a cylinder
meeting the conditions in the following table is excepted from the
puncture resistance test requirements of this section and of
Sec. 178.69(h)(3) of this subchapter:
[[Page 58482]]
------------------------------------------------------------------------
Maximum
water Minimum
filled wall
DOT specification/material gross thickness
weight (inch)
(lbs.)
------------------------------------------------------------------------
3A................................................ 215 0.180
3AA............................................... 255 0.220
------------------------------------------------------------------------
(2) Valve damage protection. Each cylinder with a valve must be
equipped with a protective cap, other valve protection device or an
overpack sufficient to protect the valve from deformation, breakage or
leakage resulting from a drop of 2.0 m (7 ft) onto a non-yielding
surface. Impact must be at an orientation most likely to cause damage.
(d) Interconnection. Cylinders may not be manifolded or
interconnected.
Sec. 173.115 [Amended]
17. In Sec. 173.115, in paragraph (c)(2), in the last sentence, the
wording ``or CGA Pamphlet P-20'' is added immediately following the
word ``subpart''.
18. In Sec. 173.115, in paragraph (j), the reference
``Sec. 173.304(a)(2)'' would be revised to read
``Sec. 173.304a(a)(2)''.
19. Section 173.163 would be revised to read as follows:
Sec. 173.163 Hydrogen fluoride.
Hydrogen fluoride (hydrofluoric acid, anhydrous) must be packaged
in specification 3, 3A, 3AA, 3B, 3BN, 3E, 4A, or 3M cylinders; or
Specification 4B, 4BA, 4BW, or 4M cylinders, if they are not brazed.
Filling density may not exceed 85 percent of the cylinder's water
weight capacity. Metric-marked cylinders must be requalified by
ultrasonic examination in accordance with Sec. 180.207 of this
subchapter. Nonmetric-marked cylinders must be requalified by
ultrasonic examination in accordance with Sec. 180.209(a)(2) of this
subchapter.
20. Section 173.192 would be revised to read as follows:
Sec. 173.192 Packaging for certain toxic gases in Hazard Zone A.
When Sec. 172.101 of this subchapter specifies that a toxic
material be packaged under this section, only specification cylinders
are authorized, as follows:
(a) Specification 3A1800, 3AA1800, 3AL1800, or 3E1800 cylinders;
3M, 3ALM, or 3FM cylinders with a marked test pressure of 200 bar (2900
psig); under the following conditions:
(1) Specification 3A, 3AA, 3AL, 3M, 3ALM, or 3FM cylinders may not
exceed 57 kg (125 pounds) water capacity (nominal).
(2) Specification 3AL or 3ALM cylinders may only be offered for
transportation or transported by highway and rail.
(b) Packagings must conform to the requirements of Sec. 173.40.
(c) For cylinders used for phosgene:
(1) The filling density may not exceed 125 percent;
(2) A cylinder may not contain more than 68 kg (150 pounds) of
phosgene; and
(3) Each cylinder containing phosgene must be tested for leakage
before it is offered for transportation or transported and must show no
leakage; this test must consist of immersing the cylinder and valve,
without the protection cap attached, in a bath of water at a
temperature of approximately 66'C (150'F) for at least 30 minutes,
during which time frequent examinations must be made to note any escape
of gas. The valve of the cylinder must not be loosened after this test.
Alternatively, each cylinder containing phosgene may be tested for
leakage by a method approved in writing by the Associate Administrator
for Hazardous Materials Safety.
Sec. 173.198 [Amended]
21. In Sec. 173.198, in paragraph (a), the reference
``Sec. 173.34(e)'' would be revised to read ``Sec. 180.205 of this
subchapter''.
22. In Sec. 173.226, paragraph (a) would be revised to read as
follows:
Sec. 173.226 Materials poisonous by inhalation, Division 6.1, Packing
Group I, Hazard Zone A.
* * * * *
(a) In seamless specification cylinders conforming to the
requirements of Sec. 173.40.
* * * * *
23. In Sec. 173.227, paragraph (a) would be revised to read as
follows:
Sec. 173.227 Materials poisonous by inhalation, Division 6.1, Packing
Group I, Hazard Zone B.
* * * * *
(a) In packagings as authorized in Sec. 173.226 and seamless and
welded specification cylinders conforming to the requirements of
Sec. 173.40.
* * * * *
24. Section 173.228 would be revised to read as follows:
Sec. 173.228 Bromine pentafluoride or bromine trifluoride.
(a) The following packagings are authorized:
(1) Specification 3A150, 3AA150, 3B240, 3BN150, 4B240, 4BA240,
4BW240 and 3E1800 cylinders;
(2) Specification 3M, 3ALM, 3FM, and 4M cylinders with a minimum
marked test pressure of 25 bar (363 psig).
(b) Material in Hazard Zones A and B must be transported in
cylinders conforming to the requirements of Sec. 173.40, except that
material in Hazard Zone A must be transported only in seamless
specification cylinders.
(c) Cylinder valves must be protected as specified in
Sec. 173.301(h). No cylinder may be equipped with any pressure relief
device.
Secs. 173.300a, 173.300b, 173.300c [Removed]
25. In part 173, Secs. 173.300a, 173.300b, and 173.300c would be
removed.
26. Section 173.301 would be revised to read as follows:
Sec. 173.301 General requirements for shipment of compressed gases in
cylinders and spherical pressure vessels.
(a) General qualifications for use of cylinders. As used in this
subpart, filled means an introduction or presence of a hazardous
material in a cylinder. A Class 2 material (gas) offered for
transportation in a cylinder must be prepared in accordance with this
section and Secs. 173.302 through 173.305.
(1) Compressed gases must be in metal cylinders and containers
built in accordance with the DOT (and ICC, as shown) specifications, as
shown in this paragraph (a)(1), in effect at the time of manufacture,
and marked as required by the specification and the regulation for
requalification if applicable:
Packagings
2P
2Q
ICC-3\1\
---------------------------------------------------------------------------
\1\ Use of existing cylinders is authorized. New construction is
not authorized after [FIVE YEARS FROM EFFECTIVE DATE OF THE FINAL
RULE], except that new construction of ICC-3 cylinders is currently
not authorized.
---------------------------------------------------------------------------
3A\1\
3AA\1\
3AL\1\
3ALM
3AX\1\
3A480X\1\
3AAX\1\
3B\1\
3BN\1\
3E
3FM
3HT
3M
3T\1\
4AA480
4B\1\
4B240ET\1\
4BA\1\
4BW\1\
4D
4DA
[[Page 58483]]
4DS
4E\1\
4L
4M
8
8AL
39
(2) A cylinder must be filled in accordance with this part. Before
each filling of a cylinder, the person filling the cylinder must
visually inspect the outside of the cylinder. A cylinder that has a
crack or leak, is bulged, has a defective valve or pressure relief
device, or bears evidence of physical abuse, fire or heat damage, or
detrimental rusting or corrosion may not be used unless it is properly
repaired and requalified as prescribed in subpart C of part 180 of this
subchapter.
(3) A cylinder that has previously contained a Class 8 material
must be requalified in accordance with Sec. 180.205(e) of this
subchapter.
(4) When a cylinder with a marked pressure limit is prescribed,
another cylinder made under the same specification but with a higher
marked pressure limit is authorized. For example, a cylinder marked
``DOT-4B500'' may be used when ``DOT-4B300'' is specified and a
cylinder marked ``DOT-3FM140'' may be used when ``DOT-3FM70'' is
authorized.
(5) No person may fill a cylinder overdue for periodic
requalification with a hazardous material and then offer it for
transportation. This requirement does not apply to a cylinder that was
filled prior to the requalification due date.
(6) After its authorized service life has expired, a cylinder may
not be offered for transportation in commerce.
(7) For nonmetric-marked cylinders, the pressure of the hazardous
material at 55 deg.C (131 deg.F) must not exceed the service pressure
of the cylinder. Sufficient outage shall be provided so that the
cylinder will not be liquid full at 55 deg.C (131 deg.F).
(8) Metric-marked cylinders containing permanent gases must be
filled in accordance with Sec. 173.302b.
(9) Metric-marked cylinders containing liquefied gases must be
filled in accordance with Sec. 173.304b.
(10) DOT 2P, 2Q, 3E, 3HT, spherical 4BA, 4D, 4DA, 4DS, 39, and
spherical 4M cylinders must be shipped in strong outside packagings.
The strong outside packaging must conform to paragraph (h) of this
section and to Sec. 173.25.
(b) Cylinder markings. Required markings on a cylinder must be
legible and must meet the applicable requirements of subpart C of part
180 of this subchapter. Additional information may be marked on the
cylinder provided it does not affect the required markings prescribed
in the applicable cylinder specification.
(c) Toxic gases and mixtures. Cylinders containing toxic gases and
toxic gas mixtures that meet the criteria of Division 2.3 Hazard Zone A
or B must conform to the requirements of Sec. 173.40, CGA Pamphlets S-
1.1 and S-7. DOT 39 cylinders may not be used for toxic gases or toxic
gas mixtures that meet the criteria for Division 2.3 Hazard Zone A or
B.
(d) Gases capable of combining chemically. A filled cylinder may
not contain any gas or material that is capable of combining chemically
with the cylinder's contents or with the cylinder material of
construction so as to endanger the cylinder's serviceability. After
[EFFECTIVE DATE OF THE FINAL RULE] DOT 3AL cylinders made of aluminum
alloy 6351 may not be filled and offered for transportation with
pyrophoric gases.
(e) Ownership of cylinder. A cylinder filled with a hazardous
materials may not be offered for transportation unless it was filled by
the owner of the cylinder or with the owner's consent.
(f) Pressure relief device systems. (1) Except as provided in
paragraph (f)(6) and (f)(7) of this section, a cylinder filled with a
gas for transportation must be equipped with one or more pressure
relief devices sized and selected as to type, location and quantity and
tested in accordance with CGA Pamphlets S-1.1 (compliance with
paragraph 9.1.1.1 of CGA Pamphlet S-1.1 is not required) and S-7. A
pressure relief device is required on a DOT 39 cylinder and a cylinder
used for acetylene in solution, regardless of cylinder size or filled
pressure. A DOT 39 cylinder used for liquefied Division 2.1 materials
must be equipped with a metal pressure relief valve. Fusible pressure
relief devices are not authorized on a DOT 39 cylinder containing a
liquefied gas.
(2) When installed, a pressure relief device must be in the vapor
space of a cylinder.
(3) For a metric-marked cylinder, the start-to-discharge pressure
of a pressure relief device may not be less than the marked test
pressure of the cylinder. For a nonmetric-marked DOT-3 series cylinder,
from the first requalification due on and after [EFFECTIVE DATE OF THE
FINAL RULE,] the start-to-discharge pressure of the pressure relief
device, may not be less than the minimum required test pressure. To
ensure that the relief device does not open below its set pressure, the
allowable tolerances for all the pressure relief devices must range
from zero to plus 10% of its setting. The pressure relief device must
be capable of preventing rupture of the normally filled cylinder when
subjected to a fire test conducted in accordance with CGA Pamphlet C-
14, or in the case of an acetylene cylinder, CGA Pamphlet C-12.
(4) Before each filling of a cylinder equipped with a pressure
relief device, the person filling the cylinder must visually inspect
each pressure relief device for corrosion, damage, rust, plugging of
external pressure relief device channels, and other mechanical defects
such as extrusion of fusible metal. A cylinder with a defective
pressure relief device may not be used.
(5) Before a filled cylinder is offered for transportation from the
cylinder filling facility, the pressure relief device must be tested
for leaks. A cylinder with a leaking pressure relief device may not be
offered for transportation.
(6) A pressure relief device is not required on----
(i) A cylinder 305 mm (12 inches) or less in length, exclusive of
neck, and 114 mm (4.5 inches) or less in outside diameter, except:
(A) When filled with a liquefied gas for which this part requires a
service pressure of 1800 psi or higher for a nonmetric-marked cylinder,
and a test pressure of 186 bar (2700 psi) or higher for a metric-marked
cylinder; or
(B) When filled with a nonliquefied gas to a pressure less than
1800 psi for a nonmetric-marked cylinder and 124 bar for a metric-
marked cylinder.
(ii) A cylinder with a water capacity of less than 454 kg (1000
lbs) filled with a nonliquefied gas to a pressure of 21 bar (300 psi)
or less at 21 deg.C (70 deg.F).
(iii) A cylinder containing a Class 3 or a Class 8 material without
pressurization unless otherwise specified for the hazardous material.
(7) A pressure relief device is prohibited on a cylinder filled
with a Division 2.3 or a Division 6.1 material in Hazard Zone A.
(g) Manifolding cylinders in transportation. (1) Cylinder
manifolding is only authorized under conditions prescribed in this
paragraph (g). Manifolded cylinders shall be supported and held
together as a unit by structurally adequate means. Except for Division
2.2 materials, each cylinder must be equipped with an individual
shutoff valve that must be tightly closed while in transit. Manifold
branch lines must be sufficiently flexible to prevent damage to the
valves which otherwise might result from the use of rigid branch lines.
Each cylinder must be individually equipped with a pressure relief
device as required in paragraph (f) of this section. Pressure relief
devices
[[Page 58484]]
on manifolded cylinders, filled with a compressed gas, must be arranged
to discharge upward and unobstructed to the open air in such a manner
as to prevent any escaping gas from contacting personnel or any
adjacent cylinders. Valves and pressure relief devices on manifolded
cylinders, filled with a compressed gas, must be protected by framing
or other method which is equivalent to the valve protection required in
paragraph (h) of this section. Manifolding is authorized for cylinders
containing the following gases:
(i) Nonliquefied compressed (permanent)gases authorized by
Sec. 173.302.
(ii) Liquefied compressed gases that are authorized by
Sec. 173.304. Each manifolded cylinder, containing a liquefied
compressed gas, must be separately filled and means must be provided to
ensure that no interchange of cylinder contents can occur during
transportation.
(iii) Acetylene as authorized by Sec. 173.303.
(2) For the checking of tare weights or for replacement of solvent,
the cylinder must be removed from the manifold. This requirement is not
intended to prohibit the filling of acetylene cylinders while
manifolded.
(h) Cylinder valve protection. (1) Except for a cylinder meeting
the following conditions, a cylinder offered for transportation must
meet the performance requirements specified in paragraph (h)(2) of this
section:
(i) A cylinder manufactured before [FIVE YEARS FROM EFFECTIVE DATE
OF THE FINAL RULE.];
(ii) A cylinder containing only a Division 2.2 material without a
Division 5.1 subsidiary hazard;
(iii) A cylinder containing a Class 9 material or a Class 8
material only corrosive to metal;
(iv) A cylinder with a water capacity of 4.8 liters (293 cubic
inches) or less containing oxygen, compressed;
(v) A cylinder containing oxygen, refrigerated liquid (cryogenic
liquid).
(2) Each cylinder valve assembly must be of sufficient strength or
protected such that no leakage occurs when a cylinder with the valve
installed is dropped 1.8 m (6 ft.) or more onto a non-yielding floor,
impacting the valve assembly or protection device at an orientation
most likely to cause damage. The cylinder valve assembly protection may
be provided by any method that meets the performance requirement in
this paragraph (h)(2), examples include:
(i) Equipping the cylinder with a securely attached metal cap.
(ii) Packaging the cylinder in a box, crate or other strong outside
packaging conforming to the requirements of Sec. 173.25.
(iii) Constructing the cylinder such that the valve is recessed
into the cylinder or otherwise protected.
(i) Cylinders mounted on motor vehicles or in frames. Seamless DOT
specification cylinders longer than two meters (6.5 feet) are
authorized for transportation only when horizontally mounted on a motor
vehicle or in an ISO framework or other framework of equivalent
structural integrity. Cylinders may be transported by rail in container
on freight car (COFC) or trailer on flat car (TOFC) service only under
conditions approved by the Associate Administrator for Safety, Federal
Railroad Administration. The cylinder must be configured as follows:
(1) Each cylinder must be fixed at one end of the vehicle or
framework with provision for thermal expansion at the opposite end
attachment;
(2) The valve and pressure relief device protective structure must
be sufficiently strong to withstand a force equal to twice the weight
of the cylinder and framework assembly with a safety factor of four,
based on the ultimate strength of the material used; and
(3) Discharge from a pressure relief device shall be arranged in
such a manner to prevent any escaping gas from contacting personnel or
any adjacent cylinders.
(j) Non-specification cylinders in domestic use. Except as provided
in paragraphs (k) and (l) of this section, a filled non-DOT
specification cylinder, other than a DOT exemption cylinder, may not be
offered for transportation or transported to, from, or within the
United States.
(k) Importation of foreign cylinders for discharge within a single
port area. A cylinder manufactured to other than a DOT specification
that has been certified as being in conformance with the transportation
regulations of another country may be authorized upon written request
to and approval by the Associate Administrator for Hazardous Materials
Safety, for transportation within a single port area, provided--
(1) The cylinder is transported in a closed freight container;
(2) The cylinder is certified by the importer to provide a level of
safety at least equal to that required by the regulations in this
subchapter for a comparable DOT specification cylinder; and
(3) The cylinder is not refilled for export unless in compliance
with paragraph (l) of this section.
(l) Charging of foreign cylinders for export. A cylinder
manufactured outside the United States that was not manufactured,
inspected, tested and marked in accordance with part 178 of this
subchapter or a cylinder manufactured to other than a DOT specification
or exemption may be filled with a gas in the United States and offered
for transportation and transported for export, if the following
conditions are met:
(1) The cylinder has been requalified and marked with the month and
year of requalification in accordance with subpart C of part 180 of
this subchapter, or has been requalified as authorized by the Associate
Administrator for Hazardous Materials Safety.
(2) The maximum filling density and service pressure for each
cylinder conform to the requirements of this part for the gas involved.
(3) The bill of lading or other shipping paper shall identify the
cylinder and shall carry the following certification: ``This cylinder
has (These cylinders have) been qualified, as required, and filled in
accordance with the DOT requirements for export.''
(m) Sharp attachments. Attachments to cylinders filled for
transportation may not have sharp corners, edges, or any other features
that are capable of causing puncture or damage to other freight.
Attachments include all permanent structural attachments, as well as
anything temporarily attached to the cylinder, such as skids.
27. Section 173.301a would be added to read as follows:
Sec. 173.301a Additional general requirements for shipment of
nonmetric-marked cylinders.
(a) General. The requirements in this section are in addition to
the requirements in Sec. 173.301 and apply to the shipment of gases in
nonmetric-marked cylinders.
(b) Authorized cylinders not marked with a service pressure. For
authorized cylinders not marked with a service pressure, the service
pressure is designated as follows:
------------------------------------------------------------------------
Service
Specification marking pressure
psig
------------------------------------------------------------------------
3.......................................................... 1800
3E......................................................... 1800
8.......................................................... 250
------------------------------------------------------------------------
(c) Cylinder pressure at 21 deg.C (70 deg.F). The pressure in a
cylinder at 21 deg.C (70 deg.F) may not exceed the service pressure for
which the cylinder is marked or designated, except as provided in
Sec. 173.302a(b). For certain liquefied
[[Page 58485]]
gases, the pressure at 21 deg.C (70 deg.F) must be lower than the
marked service pressure to avoid having a pressure at a temperature of
54.4 deg.C (131 deg.F) that is greater than permitted.
(d) Cylinder pressure at 55 deg.C (131 deg.F). The pressure in a
cylinder at 55 deg.C (131 deg.F) may not exceed \5/4\ times the service
pressure, except:
(1) A cylinder filled with acetylene, liquefied nitrous oxide or
carbon dioxide.
(2) When a cylinder is filled in accordance with Sec. 173.302a(b),
the pressure in the cylinder at 55 deg.C (131 deg.F) may not exceed \5/
4\ times the filling pressure.
28. Section 173.301b would be added to read as follows:
Sec. 173.301b Additional general requirements for shipment of metric-
marked cylinders.
(a) Definitions. For purposes of this subpart, the following
definitions apply to Class 2 materials in metric-marked cylinders:
Critical temperature means the temperature above which the
substance can not exist in the liquid state.
Dissolved gas means a gas which is dissolved under pressure in a
liquid phase solvent. The solvent may be supported in a porous mass.
Filling factor of liquefied compressed gas means the mass of a gas,
in kg (or pound), which can be filled into a 1 liter (61 cubic inches)
water capacity container. The filling factor of each liquefied
compressed gas must be calculated to meet all requirements of
Sec. 173.304b.
High pressure liquefied compressed gas means a gas which has a
critical temperature in the range from -10 deg.C (14 deg.F) to less
than 70 deg.C (158 deg.F).
Low pressure liquefied compressed gas means a gas which has a
critical temperature equal to or above 70 deg.C (158 deg.F).
Permanent (non-liquefied compressed) gas means a gas other than in
solution, which has a critical temperature below -10 deg.C (14
deg.F).
Safety factor means the ratio of the cylinder burst pressure to its
marked test pressure. For example, a cylinder with a marked test
pressure of 180 bar (2610 psi) and a burst pressure of 340 bar (4930
psi) and has a safety factor of 1.89.
Settled pressure (formerly referred to as service pressure) means
the pressure of the contents of the cylinder at 15 deg.C (59 deg.F).
(b) Pressure in cylinders containing a permanent gas. The pressure
in a DOT 3M, 3FM, 3ALM or 4M cylinder containing a permanent gas must
be as prescribed in Sec. 173.302b.
(c) Pressure in cylinders containing a liquefied compressed gas.
(1) The pressure in a cylinder containing a liquefied compressed gas
which has critical temperature ranging from -10 deg.C (14 deg.F) up
to 70 deg.C (158 deg.F) may not exceed the cylinder's marked test
pressure or be liquid full at a temperature of 65 deg.C (149 deg.F).
(2) The pressure in a cylinder containing a liquefied compressed
gas which has a critical temperature greater than or equal to 70 deg.C
(158 deg.F) may not exceed the cylinder's marked test pressure or be
liquid full at 54 deg.C (130 deg.F).
(d) Authorized gases for DOT 3FM cylinders. A DOT 3FM cylinder may
only be used for gases free of corroding components with a dew point
below -49 deg.C (-56 deg.F). A DOT 3FM cylinder is not authorized for
hydrogen or hydrogen bearing gases (e.g., hydrogen sulfide).
29. Section 173.302 would be revised to read as follows:
Sec. 173.302 Filling of cylinders with non-liquefied compressed gases.
(a) General requirements. A cylinder filled with a non-liquefied
compressed gas (except gas in solution) must be offered for
transportation in accordance with the requirements of this section and
Secs. 173.301, 173.301a, 173.301b, 173.302a, 173.302b and 173.305.
Where more than one section applies to a cylinder, the most restrictive
requirement must be followed.
(b) Aluminum cylinders in oxygen service. Each aluminum cylinder
filled with oxygen must meet the following conditions:
(1) Each cylinder must be equipped only with brass or stainless
steel valves;
(2) Each cylinder must have only straight threads in the opening;
(3) Each cylinder must be cleaned in accordance with the
requirements of Federal Specification RR-C-901c, paragraphs 3.7.2, and
3.8.2. Cleaning agents equivalent to those specified in RR-C-901c may
be used provided they do not react with oxygen. One cylinder selected
at random from a group of 200 or less and cleaned at the same time,
must be tested for oil contamination in accordance with Specification
RR-C-901c, paragraph 4.4.2.3, and meet the standard of cleanliness
specified; and
(4) The pressure in each cylinder may not exceed 207 bar (3000
psig) at 21 deg.C (70 deg.F).
(c) Each authorized cylinder containing oxygen which is
continuously fed to tanks containing live fish may be offered for
transportation and transported irrespective of the provisions of
Sec. 173.24(b)(1).
(d) Shipment of Division 2.1 materials in aluminum cylinders are
authorized only when transported by highway, rail, or cargo-only
aircraft.
30. Section 173.302a would be added to read as follows:
Sec. 173.302a Additional requirements for shipment of permanent
(nonliquefied) compressed gases in nonmetric-marked cylinders.
(a) Detailed filling requirements. Nonliquefied compressed gases
(except gas in solution) for which filling requirements are not
specifically prescribed in Sec. 173.304a must be shipped, subject to
the requirements in this section and Secs. 173.301, 173.301a, 173.302
and 173.305 in nonmetric-marked cylinders, as follows:
(1) Specification 3, 3A, 3AA, 3AL, 3B, 3E, 4B, 4BA and 4BW
cylinders.
(2) DOT 3HT cylinders. These cylinders are authorized for aircraft
use only and only for nonflammable gases. They have a maximum service
life of 24 years from the date of manufacture. The cylinders must be
equipped with pressure relief devices only of the frangible disc type
which meet the requirements of Sec. 173.301(f). Each frangible disc
must have a rated bursting pressure which does not exceed 90 percent of
the minimum required test pressure of the cylinder. Discs with fusible
metal backing are not permitted. Specification 3HT cylinders may be
offered for transportation only when packed in strong outer packagings
conforming to the requirements of Sec. 173.25.
(3) For a specification 39 cylinder filled with a Division 2.1
material, the internal volume may not exceed 75 cubic inches.
(4) Specification 3AX, 3AAX, and 3T cylinders are authorized for
Division 2.1 and 2.2 materials and for carbon monoxide. DOT 3T
cylinders are not authorized for hydrogen. When used in methane
service, the methane must be a non-liquefied gas which has a minimum
purity of 98.0 percent methane and which is commercially free of
corroding components.
(5) Aluminum cylinders made to DOT specification 39 and 3AL are
authorized for oxygen only under the conditions specified in
Sec. 173.302(b).
(b) Special filling limits for specification 3A, 3AX, 3AA, 3AAX,
and 3T cylinders. A specification 3A, 3AX, 3AA, 3AAX, and 3T cylinders
may be filled with a compressed gas, other than a liquefied, dissolved,
Division 2.3 or 2.1 material, to a pressure 10 percent in excess of its
marked service pressure, provided:
[[Page 58486]]
(1) The cylinder is equipped with a frangible disc pressure relief
devices (without fusible metal backing) having a bursting pressure not
exceeding the minimum prescribed test pressure.
(2) The cylinder's elastic expansion was determined at the time of
the last test or retest by the water jacket method.
(3) Either the average wall stress or the maximum wall stress does
not exceed the wall stress limitation shown in the following table:
------------------------------------------------------------------------
Average Maximum
wall wall
Type of steel stress stress
limitation limitation
------------------------------------------------------------------------
Plain carbon steels over 0.35 carbon and medium
manganese steels............................... 53,000 58,000
Steels of analysis and heat-treatment specified
in spec. 3AA................................... 67,000 73,000
Steel of analysis and heat treatment specified
in spec. DOT-3T................................ 87,000 94,000
Plain carbon steels less than 0.35 carbon made
prior to 1920.................................. 45,000 48,000
------------------------------------------------------------------------
(i) The average wall stress shall be computed from the elastic
expansion data using the following formula:
S = 1.7EE / KV--0.4P
Where:
S = wall stress, pounds per square inch;
EE = elastic expansion (total less permanent) in cubic centimeters;
K = factor x 10-7 experimentally determined for the
particular type of cylinder being tested or derived in accordance with
CGA Pamphlet C-5;
V = internal volume in cubic centimeter (1 cubic inch = 16.387 cubic
centimeters);
P = test pressure, pounds per square inch.
(ii) The maximum wall stress shall be computed from the formula:
S = (P(1.3D2 + 0.4d2)) / (D2-
d2)
Where:
S = wall stress, pounds per square inch;
P = test pressure, pounds per square inch;
D = outside diameter, inches;
d = D-2t, where t=minimum wall thickness determined by a suitable
method.
(iii) The formula in paragraph (b)(3)(i) of this section is derived
from the formula in paragraph (b)(3)(ii) and the following:
EE = (PKVD2) / (D2-d2)
(iv) Compliance with average wall stress limitation may be
determined through computation of the elastic expansion rejection limit
in accordance with CGA Pamphlet C-5 or through the use of the
manufacturer's marked elastic expansion rejection limit (REE) on the
cylinder.
(4) That an external and internal visual examination made at the
time of test or retest shows the cylinder to be free from excessive
corrosion, pitting, or dangerous defects.
(5) That a plus sign (+) be added following the test date marking
on the cylinder to indicate compliance with paragraphs (b) (2), (3),
and (4) of this section.
(c) Carbon monoxide. Carbon monoxide must be offered in a
specification 3, 3A, 3AX, 3AA, 3AAX, 3AL, 3E, or 3T cylinder having a
minimum service pressure of 1,800 psig. The pressure in the cylinder
may not exceed 1000 psig at 70 deg. F., except that if the gas is dry
and sulfur free, the cylinder may be filled to five-sixths of the
cylinder's service pressure or 2000 psig, whichever is less. A DOT 3AL
cylinder is authorized only when transported by highway, rail or cargo-
only aircraft.
(d) Diborane and diborane mixtures. Diborane and diborane mixed
with compatible compressed gas must be offered in a DOT 3AA1800
cylinder. The maximum filling density of the diborane may not exceed 7
percent. Diborane mixed with compatible compressed gas may not have a
pressure exceeding the service pressure of the cylinder if complete
decomposition of the diborane occurs. Cylinder valve assembles must be
protected in accordance with Sec. 173.301(h).
(e) Fluorine. Fluorine must be offered in a DOT 3A1000, 3AA1000, or
3BN400 cylinder without a pressure relief device and equipped with a
valve protection cap. The cylinder may not be filled to over 400 psig
at 70 deg. F. and may not contain over 6 pounds of gas.
31. Section 173.302b would be added to read as follows:
Sec. 173.302b Additional requirements for shipment of permanent gases
in metric-marked cylinders.
(a) General requirements. Permanent gases (except gas in solution)
must be shipped, subject to this section and Secs. 173.301, and
173.301b in a DOT specification 3ALM, 3M, 3FM or 4M cylinder.
(1) A cylinder with a marked test pressure greater than or equal to
35 bar (508 psi) is authorized for transportation of Division 2.1, 2.2,
or 2.3 Hazard Zone B,C or D gas.
(2) A DOT 3ALM, 3M, or 3FM cylinder with a marked test pressure
greater than or equal to 200 bar (2900 psi) is authorized for
transportation of Division 2.3 Hazard Zone A gases.
(3) The settled pressure for a DOT 3M, 3FM or 3ALM cylinder may not
exceed two-thirds of the cylinder's marked test pressure.
(4) The settled pressure for a DOT 4M cylinder and a DOT 3M
cylinder made from nickel may not exceed one-half of the cylinder's
marked test pressure.
(5) A DOT 3FM cylinder exceeding 454 kilogram (1000 pounds) water
capacity is authorized for dry compressed natural gas (scrubbed to
remove acid gases). The cylinder may not contain any liquefied gas and
the gas must meet following conditions:
(i) Water content is less than or equal to 0.5 lb. per million
cubic feet at standard temperature and pressure (STP) (60 deg. F., 30
inches Hg).
(ii) Hydrogen Sulfide and Mercaptan Sulfur in Natural Gas is less
than or equal to 0.1 grain per 100 cubic feet.
(iii) Total Soluble Sulfides other than Hydrogen Sulfide must be
less than or equal to 0.1 grain per 100 cubic feet at STP.
(iv) Less than one percent by volume of oxygen.
(v) Less than three percent by volume of carbon dioxide.
(b) Pressure Limit. Pressure in a cylinder containing a permanent
gas at 70 deg.C (158 deg.F) may not exceed the values in the
following table:
------------------------------------------------------------------------
Percentage
of
cylinder's
Division marked
test
pressure
------------------------------------------------------------------------
2.3, Zone A................................................. 63
2.3, Zone B, C.............................................. 70
2.1/5.1; 2.3, Zone D........................................ 78
2.2......................................................... 100
------------------------------------------------------------------------
(c) Fluorine. Fluorine must be shipped in DOT 3M or 4M cylinders
without pressure relief devices. The settled pressure may not exceed
\1/4\ of the cylinder's marked test pressure, or be more than 28 bar
(400 psig) at 21 deg.C (70 deg.F). The cylinder may not contain over
2.7 kg (6 pounds) of gas.
(d) Carbon monoxide. A cylinder filled with carbon monoxide may not
exceed \1/3\ of the cylinder's marked test pressure, except that if the
gas is dry and sulfur free, settled pressure may not exceed \1/2\ of
the cylinder's marked test pressure.
(e) Diborane and diborane mixtures. Diborane and diborane mixed
with a compatible compressed gas must be
[[Page 58487]]
shipped in a DOT 3M cylinder and the settled pressure may not exceed
\1/3\ of the cylinder's marked test pressure. The maximum filling
density of the diborane may not exceed 7 percent. Diborane mixed with a
compatible compressed gas may not have a settled pressure exceeding \2/
3\ of the cylinder's marked test pressure if complete decomposition of
the diborane occurs. The cylinder valve must be protected in accordance
with Sec. 173.301(h).
32. Section 173.304 would be revised to read as follows:
Sec. 173.304 Filling of cylinders with liquefied compressed gases.
(a) General requirements. Liquefied compressed gases (except gas in
solution) must be shipped in accordance with the requirements in this
section and in Secs. 173.301, 173.301a, 173.301b, 173.304a, 173.304b
and 173.305.
(1) DOT 3AL, 3ALM, 3FM and 4M cylinders may not be used for any
material that has a primary or subsidiary hazard of Class 8.
(2) Shipments of Division 2.1 materials in aluminum cylinders are
authorized only when transported by highway, rail or cargo-only
aircraft.
(b) Filling limits. Except for carbon dioxide, 1,1-Difluoroethylene
(R-1132A), nitrous oxide and vinyl fluoride, inhibited, the liquid
portion of a liquefied gas may not completely fill the packaging at any
temperature up to and including 54 deg. C (130 deg. F). The liquid
portion of vinyl fluoride, inhibited, may completely fill the cylinder
at 54 deg. C (130 deg. F) provided; the pressure at the critical
temperature does not exceed one and one-fourth times the service
pressure of a nonmetric-marked cylinder; or the pressure at the
critical temperature does not exceed 83% of the test pressure of a
metric-marked cylinder.
(c) Mixture of compressed gas and other material. A mixture of
compressed gas must be shipped in accordance with Sec. 173.305.
(d) Refrigerant gases. Refrigerant gases which are nontoxic and
nonflammable under this part, must be offered for transportation in
cylinders prescribed in Secs. 173.304a, 173.304b, or in DOT 2P and 2Q
containers (Secs. 178.33, 178.33a of this subchapter). DOT 2P and 2Q
containers must be packaged in a strong wooden or fiberboard box of
such design as to protect valves from injury or accidental functioning
under conditions incident to transportation. Pressure in the inside
metal containers may not exceed 6 bar absolute (87 psia) at 21 deg. C
(70 deg. F). Each completed metal container filled for shipment must be
heated until its contents reach a temperature of 54 deg. C (130 deg. F)
without evidence of leakage, distortion, or other defect. Each outside
package must be plainly marked ``INSIDE CONTAINERS COMPLY WITH
PRESCRIBED SPECIFICATIONS.''
(e) Engine starting fluid. Engine starting fluid containing a
flammable compressed gas or gases must be shipped in a cylinder as
prescribed in Sec. 173.304a, 173.304b, or as follows:
(1) Inside nonrefillable metal containers having a capacity not
greater than 500 ml (32 cubic inches). The containers must be packaged
in strong, tight outer packagings. The pressure in the container may
not exceed 10 bar absolute (145 psia), at 54 deg.C (130 deg.F).
However, if the pressure exceeds 10 bar absolute (145 psia), at 54
deg.C (130 deg.F), a DOT 2P container must be used. In any event, the
metal container must be capable of withstanding, without bursting, a
pressure of one and one-half times the pressure of the content at 54
deg.C (130 deg.F). The liquid content of the material and gas must not
completely fill the container at 54 deg.C (130 deg.F). Each
container, filled for shipment, must have been heated until its
contents reach a temperature of 54 deg.C (130 deg.F), without
evidence of leakage, distortion, or other defect. Each outside shipping
container must be plainly marked, ``INSIDE CONTAINERS COMPLY WITH
PRESCRIBED SPECIFICATIONS.''
(2) [Reserved]
33. Section 173.304a would be added to read as follows:
Sec. 173.304a Additional requirements for shipment of liquefied
compressed gases in nonmetric-marked cylinders.
(a) Detailed filling requirements. Liquefied gases (except gas in
solution), must be offered for transportation, subject to the
requirements in this section and Secs. 173.301, 173.301a and 173.304,
in nonmetric-marked cylinders, as follows:
(1) Specification 3, 3A, 3AA, 3B, 3BN, 3E, 4B, 4BA, 4B240ET, 4BW,
4E, 39, except that no Specification 4E or 39 packaging may be filled
and shipped with a mixture containing a pyrophoric liquid, carbon
bisulfide (disulfide), ethyl chloride, ethylene oxide, nickel carbonyl,
spirits of nitroglycerin, or toxic material (Division 6.1 or 2.3),
unless specifically authorized in this part.
(2) The following requirements must be complied with for the gases
named (for cryogenic liquids, see Sec. 173.316):
----------------------------------------------------------------------------------------------------------------
Containers marked as shown in this column or of
Maximum permitted the same type with higher service pressure must
Kind of gas filling density be used except as provided in 173.301(1),
(percent) (See Note 1) 173.301(a)(4) (see notes following table)
----------------------------------------------------------------------------------------------------------------
Anhydrous ammonia.................... 54..................... DOT-4; DOT-3A480; DOT-3AA480; DOT-3A480X; DOT-
4A480; DOT-3; DOT-4AA480; DOT-3E1800; DOT-
3AL480.
Bromotrifluoromethane (R-13B1 or H- 124.................... DOT-3A400; DOT-3AA400; DOT-3B400; DOT-4A400; DOT-
1301). 4AA480; DOT-4B400; DOT-DOT-4BA400; DOT-4BW400;
DOT-3E1800; DOT-39; DOT-3AL400.
Carbon dioxide (see notes 4, 7, and 68..................... DOT-3A1800; DOT-3AX1800; DOT-3AA1800; DOT-
8). 3AAX1800; DOT-3; DOT-3E1800; DOT-3T1800; DOT-
3HT2000; DOT-39; DOT-DOT-4L.
Carbon dioxide, refrigerated liquid 125.................... DOT-3AL1800. DOT-3A480; DOT-3AA480; DOT-3; DOT-
(see paragraph (e) of this section.) 3BN480; DOT-3E1800.
Chlorine (see Note 2).
Chlorodifluroethane (R-142b) or 1- 100.................... DOT-3A150; DOT-3AA150; DOT-3B150; DOT-3E1800;
Chloro-1, 4B150; DOT-4BA225; DOT- DOT-39, DOT-3AL150.
4BW225; DOT-1-difluoroethane (Note
8).
Chlorodifluoromethane (R-22) (see 105.................... DOT-3A240; DOT-3AA240; DOT-3B240; DOT- 4B240;
Note 8). DOT-4BA240; DOT-4BW240; DOT-4B240ET; DOT-4E240;
DOT-39; DOT-41; DOT-3E1800; and DOT-3AL240.
Chloropentafluorethane, (R-115)...... 110.................... DOT-3A225; DOT-3AA225; DOT-3B225; DOT-4A225; DOT-
4BA225; DOT-4B225; DOT-4BW225; DOT-3E1800; DOT-
39; and DOT-3AL225.
Chlorotrifluoromethane (R-13) (see 100.................... DOT-3A1800; DOT-3AA1800; DOT-3; DOT-3E1800; DOT-
Note 8). 39; and DOT-3AL1800.
[[Page 58488]]
Cyclopropane (see Note 8)............ 55..................... DOT-3A225; DOT-3A480X; DOT-3AA225; DOT-3B225;
DOT-4A225; DOT-4AA480; DOT4B225; DOT-4BA225;
DOT-4BW225; DOT-4B240ET; DOT-3; DOT-3E1800; DOT-
39;DOT-3AL225.
Dichlorodifluoromethane (R-12) (see 119.................... DOT-3A225; DOT-3AA225; DOT-3B225;DOT- 4A225; DOT-
Note 8). 4B225; DOT-4BA225; DOT-4BW225; DOT-4B240ET; DOT-
4E225;DOT-9; DOT-39; DOT-41; DOT-3E1800; and
DOT-3AL225.
Dichlorodifluoromethane and Not liquid full at 130 DOT-3A240; DOT-3AA240, DOT-3B240; DOT-3E1800;
difluoroethane mixture (constant deg.F. DOT-4A240; DOT-4B240; DOT-4BA240; DOT-4BW240;
boiling mixture) (R-500)(Note 8). DOT-4E240; DOT-9, DOT-39.
1,1-Difluoroethane (R-152a) (see Note 79..................... DOT-3A150; DOT-3AA150; DOT-3B150;DOT-4B150; DOT-
8). 4BA225; DOT-4BW225; DOT-3E1800; DOT-3AL150.
1,1-Difluoroethylene (R-1132A)....... 73..................... DOT-3A2200, DOT-3AA2200, DOT-3AX2200, DOT-
3AAX2200, DOT-3T2200, DOT-39.
Dimethylamine, anhydrous............. 59..................... DOT-3A150; DOT-3AA150; DOT-3B150; DOT-4B150 DOT-
4BA225; DOT-4BW225; ICC-3E1800.
Ethane (see Note 8).................. 35.8................... DOT-3A1800; DOT-3AX1800; DOT-3AA1800; DOT-
3AAX1800; DOT-3; DOT-3E1800; DOT-3T1800; DOT-
39; DOT-3AL1800.
Ethane (see Note 8).................. 36.8................... DOT-3A2000; DOT-3AX2000; DOT-3AA2000; DOT-
3AAX2000; DOT-3T2000; DOT-39; DOT-3AL2000.
Ethylene (see Note 8)................ 31.0................... DOT-3A1800; DOT-3AX1800 DOT-3AA1800; DOT-
3AAX1800; DOT-3; DOT-3E1800; DOT-3T1800; DOT-
39; and DOT-3AL1800 .
Ethylene (see Note 8)................ 32.5................... DOT-3A2000; DOT-3AX2000; DOT-3AA2000; DOT-
3AAX2000; DOT-3T2000; DOT-39; and DOT-3AL2000.
Ethylene (see Note 8)................ 35.5................... DOT-3A2400; DOT-3AX2400; DOT-3AA2400; DOT-
3AAX2400; DOT-3T2400; DOT-39; DOT-3AL2400.
Hydrogen chloride, anhydrous......... 65..................... DOT-3A1800; DOT-3AA1800; DOT-3AX1800; DOT-
3AAX1800; DOT-3; DOT-3T1800; DOT-3E1800.
Hydrogen sulfide (see Note 10)....... 62.5................... DOT-3A480; DOT-3AA480; DOT-3B480; DOT-14A480;
DOT-4B480; DOT-4BA480; DOT-4BW480.; DOT-3E1800;
DOT-3AL480.
Insecticide, gases liquefied (See Not liquid full at 130 DOT-3A300; DOT-3AA300; DOT-3B300; DOT-4B300; DOT-
Notes 8 and 12). deg.F. 4BA300; DOT-4BW300; DOT-9; DOT-40; DOT-41; DOT-
3E1800.
Liquefied nonflammable gases, liquid Not liquid full at 130 Specification packaging authorized in paragraph
other than classified flammable, deg.F. (a)(1) of this section and DOT-3HT; DOT 4D; DOT-
corrosive, toxic & mixtures or 4DA; DOT-4DS.
solution thereof filled w/nitrogen
carbon dioxide, or air (see Notes 7
and 8).
Methyl acetylene-propadiene, Not liquid full at 130 DOT-4B240 without brazed seams; DOT-4BA240
mixtures, stabilized (see Note 5). deg.F. without brazed seams; DOT-3A240; DOT-3AA240;
DOT-3B240; DOT-3E1800;DOT-4BW240; DOT-4E240;
DOT-4B240ET;DOT-4;DOT-41; DOT-3AL240.
Methyl chloride...................... 84..................... DOT-3A225; DOT-3AA225; DOT-3B225; DOT-4A225; DOT-
4B225; DOT-4BA225; DOT-4BW225; DOT-3; DOT-4;
DOT-38; DOT-3E1800; DOT-4B240ET.
Cylinders complying with DOT-3A150; DOT-3B150;
DOT-4A150, and DOT-4B150 manufactured prior to
Dec. 7, 1936 are also authorized.
Methyl mercaptan..................... 80..................... DOT-3A240; DOT-3AA240; DOT-3B240; DOT-4B240; DOT-
4B240ET; DOT-3E1800; DOT-4BA240; DOT-4BW240.
Nitrosyl chloride.................... 110.................... DOT-3BN400 only.
Nitrous oxide (see Notes 7, 8, and 68..................... DOT-3A1800; DOT-3AX1800; DOT-3AA1800; DOT-
11). 3AAX1800; DOT-3; DOT-3E1800; DOT-3T1800; DOT-
3HT2000; DOT-39; DOT-3AL1800.
Nitrous oxide, refrigerated liquid DOT-4L.
(see paragraph (e) of this section.).
Refrigerant gas, n.o.s. or Dispersant Not liquid full at 130 DOT-3A240; DOT-3AA240; DOT-3B240; DOT-3E1800;
gas, n.o.s. (see Notes 8 and 13). deg.F. DOT-4A240; DOT-4B240; DOT-4BA240; DOT-4BW240;
DOT-4E240; DOT-9; DOT-39; and DOT-3AL240.
Sulfur dioxide (see note 8).......... 125.................... DOT-3A225; DOT-3AA225; DOT-3B225; DOT-4A225; DOT-
4B225; DOT-4BA225; DOT-4BW225; DOT-4B240ET; DOT-
3; DOT-4; DOT-38; DOT-39; DOT-3E1800; and DOT-
3AL225.
Sulfur hexafluoride.................. 120.................... DOT-3A1000; DOT-3AA1000; DOT-3AAX2400; DOT-3;
DOT-3AL1000; DOT-3E1800; DOT-3T1800.
Sulfuryl fluoride.................... 106.................... DOT-3A480; DOT-3AA480; DOT-3E1800; DOT-4B480;
DOT-4BA480; DOT-4BW480.
Tetrafluoroethylene/inhibit.......... 90..................... DOT-3A1200; DOT-3AA1200; DOT-3E1800.
Trifluorochloroethylene, inhibited... 115.................... DOT-3A300; DOT-3AA300; DOT-3B300; DOT-4A300; DOT-
4B300; DOT-4BA300; DOT-4BW300; DOT-3E1800.
Trimethylamine, anhydrous............ 57..................... DOT-3A150; DOT-3AA150; DOT-3B150; DOT-4B150; DOT-
4BA225; DOT-4BW225; DOT-3E1800.
Vinyl chloride (see Note 5).......... 84..................... DOT-4B150 without brazed seams; DOT-4BA225
without brazed seams; DOT-4BW225; DOT-3A150;
DOT-3AA150; DOT-3E1800; DOT-3AL150.
Vinyl fluoride, inhibited............ 62..................... DOT-3A1800; DOT-3AA1800; DOT-3E1800; DOT-
3AL1800.
[[Page 58489]]
Vinyl methyl ether, inhibited (see 68..................... DOT-4B150, without brazed seams; DOT-4BA225
Note 5). without brazed seams; DOT-4BW225; DOT-3A150;
DOT-3AA150; DOT-3B1800; DOT-3E1800.
----------------------------------------------------------------------------------------------------------------
Note 1: ``Filling density'' means the percent ratio of the weight of gas in a container to the weight of water
that the container will hold at 60 deg.F. (1 lb of water=27.737 cubic inches at 60 deg.F.).
Note 2: Cylinders purchased after Oct. 1, 1944, for the transportation of chlorine must contain no aperture
other than that provided in the neck of the cylinder for attachment of a valve equipped with an approved
pressure relief device. Cylinders purchased after Nov. 1, 1935, and filled with chlorine must not contain over
150 pounds of gas.
Note 3: [Reserved]
Note 4: Special carbon dioxide mining devices containing a heating element and filled with not over 6 pounds of
carbon dioxide may be filled to a density of not over 85 percent, provided the cylinder is made of steel with
a calculated bursting pressure in excess of 39,000 psi, be fitted with a frangible disc that will operate at
not over 57 percent of that pressure, and be able to withstand a drop of 10 feet when striking crosswise on a
steel rail while under a pressure of at least 3,000 psi. Such devices must be shipped in strong boxes or must
be wrapped in heavy burlap and bound by 12-gauge wire with the wire completely covered by friction tape.
Wrapping must be applied so as not to interfere with the functioning of the frangible disc pressure relief
device. Shipments must be described as ``liquefied carbon dioxide gas (mining device)'' and marked, labeled,
and certified as prescribed for liquefied carbon dioxide.
Note 5: All parts of valve and pressure relief devices in contact with contents of cylinders must be of a metal
or other material, suitably treated if necessary, which will not cause formation of any acetylides.
Note 6: [Reserved]
Note 7: Specification 3HT cylinders for aircraft use only, having a maximum service life of 24 years. Authorized
only for nonflammable gases. Cylinders must be equipped with pressure relief devices only of the frangible
disc type which meet the requirements of Sec. 173.301(f) Each frangible disc must have a rated bursting
pressure which does not exceed 90 percent of the minimum required test pressure of the cylinder. Discs with
fusible metal backing are not permitted. Cylinders may be shipped only when packed in strong outside
packagings.
Note 8: See Sec. 173.301(a)(10).
Note 9: [Reserved]
Note 10: Each valve outlet must be sealed by a threaded cap or a threaded solid plug.
Note 11: Must meet the valve and cleaning requirements in Sec. 173.302(b).
Note 12: For an insecticide gas which is nontoxic and nonflammable, see Sec. 173.305(c).
Note 13: For a refrigerant or dispersant gas which is nontoxic and nonflammable, see Sec. 173.304(d).
(3) The internal volume of a Specification 39 cylinder may not
exceed 75 cubic inches for a liquefied flammable gas.
(b) [Reserved]
(c) Verification of content in cylinder. Except as noted in
paragraph (d)(4) of this section, the amount of liquefied gas filled
into a cylinder must be by weight or, when the gas is lower in pressure
than required for liquefaction, a pressure-temperature chart for the
specific gas may be used to ensure that the service pressure at 21 deg.
C (70 deg. F) times 5/4 will not be exceeded at 54 deg. C (130 deg. F).
The weight of liquefied gas filled into the container also must be
checked, after disconnecting the cylinder from the filling line, by the
use of a proper scale.
(d) Requirements for liquefied petroleum gas. (1) Filling density
limited as follows:
------------------------------------------------------------------------
Maximum the
filling
density in
percent of
Minimum specific gravity of liquid material at 60 deg.F the water-
weight
capacity of
the
cylinder
------------------------------------------------------------------------
0.271 to 0.289............................................. 26
0.290 to 0.306............................................. 27
0.307 to 0.322............................................. 28
0.323 to 0.338............................................. 29
0.339 to 0.354............................................. 30
0.355 to 0.371............................................. 31
0.372 to 0.398............................................. 32
0.399 to 0.425............................................. 33
0.426 to 0.440............................................. 34
0.441 to 0.452............................................. 35
0.453 to 0.462............................................. 36
0.463 to 0.472............................................. 37
0.473 to 0.480............................................. 38
0.481 to 0.488............................................. 39
0.489 to 0.495............................................. 40
0.496 to 0.503............................................. 41
0.504 to 0.510............................................. 42
0.511 to 0.519............................................. 43
0.520 to 0.527............................................. 44
0.528 to 0.536............................................. 45
0.537 to 0.544............................................. 46
0.545 to 0.552............................................. 47
0.553 to 0.560............................................. 48
0.561 to 0.568............................................. 49
0.569 to 0.576............................................. 50
0.577 to 0.584............................................. 51
0.585 to 0.592............................................. 52
0.593 to 0.600............................................. 53
0.601 to 0.608............................................. 54
0.609 to 0.617............................................. 55
0.618 to 0.626............................................. 56
0.627 to 0.634............................................. 57
------------------------------------------------------------------------
(2) Subject to Sec. 173.301a(d), any filling density percentage
prescribed in this section is authorized to be increased by 2 for
liquefied petroleum gas in specification 3 cylinders or in
specification 3A cylinders marked for 1,800 psig, or higher, service
pressure.
(3) Liquefied petroleum gas must be shipped in specification
cylinders as follows:
(i) Specification 3, 3A, 3AA, 3B, 3E, 3AL, 4B, 4BA, 4B240ET, 4BW,
4E, or 39 cylinders. Shipments of flammable gases in 3AL cylinders are
authorized only when transported by highway, rail or cargo-only
aircraft.
(ii) Additional containers may be used within the limits of
quantity and pressure as follows:
----------------------------------------------------------------------------------------------------------------
Maximum
Type of container capacity cubic Maximum charging pressure--psig
inches
----------------------------------------------------------------------------------------------------------------
DOT-2P or DOT-2Q (see Note 1)............ 31.83 45 psig at 70 deg.F. and 105 psig at 130 deg.F.
(see Note 2).
[[Page 58490]]
DOT-2P or DOT-2Q (see Note 1)............ 31.83 35 psig at 70 deg.F. and 100 psig at 130 deg.F.
----------------------------------------------------------------------------------------------------------------
Note 1: Containers must be packed in strong wooden or fiber boxes of such design as to protect valves from
damage or accidental functioning under conditions normally incident to transportation. Each completed
container filled for shipment must have been heated until its contents reach a temperature of 130 deg.F.,
without evidence of leakage, distortion, or other defect. Each outside shipping container must be plainly
marked ``INSIDE CONTAINERS COMPLY WITH PRESCRIBED SPECIFICATIONS.''
Note 2: A container must be equipped with a pressure relief device which will prevent rupture of the container
and dangerous projection of a closing device when exposed to fire.
(4) Verification of content. Cylinders with a water capacity of 200
pounds or more and for use with a liquefied petroleum gas with a
specific gravity at 60 deg.F. of 0.504 or greater may have the
quantity of their contents determined by using a fixed length dip tube
gauging device. The length of the dip tube shall be such that when a
liquefied petroleum gas, with a specific volume of 0.03051 cu. ft./lb.
at a temperature of 40 deg.F., is filled into the container the liquid
just reaches the bottom of the tube. The weight of this liquid may not
exceed 42 percent of the water capacity of the container which must be
stamped thereon. The length of the dip tube, expressed in inches
carried out to one decimal place and prefixed with the letters ``DT''
shall be stamped on the container and on the exterior of removable type
dip tube; for the purpose of this requirement the marked length shall
be expressed as the distance measured along the axis of a straight tube
from the top of the boss through which the tube is inserted to the
proper level of the liquid in the container. The length of each dip
tube shall be checked when installed by weighing each container after
filling except when installed in groups of substantially identical
containers in which case one of each 25 containers shall be weighed.
The quantity of liquefied gas in each container must be checked by
means of the dip tube after disconnecting from the filling line. The
outlet from the dip tube shall be not larger than a No. 54 drill size
orifice. A container representative of each day's filling at each
charging plant shall have its contents checked by weighing after
disconnecting from the filling line.
(e) Carbon dioxide, refrigerated liquid or nitrous oxide,
refrigerated liquid. (1) The following provisions apply to carbon
dioxide, refrigerated liquid and nitrous oxide, refrigerated liquid:
(i) DOT 4L cylinders conforming to the provisions of this paragraph
are authorized.
(ii) Each cylinder must be protected with at least one pressure
relief device and at least one frangible disc conforming to
Sec. 173.301(f) and paragraph (a)(2) of this section. The relieving
capacity of the pressure relief device system must be equal to or
greater than that calculated by the applicable formula in paragraph 5.9
of CGA Pamphlet S-1.1.
(iii) The temperature and pressure of the gas at the time the
shipment is offered for transportation may not exceed -18 deg.C (0
deg.F) and 20 bar (290 psig) for carbon dioxide and -15.6 deg.C (+4
deg.F) and 20 bar(290 psig) for nitrous oxide. Maximum time in transit
may not exceed 120 hours.
(2) The following pressure relief device settings, design service
temperatures and filling densities apply:
----------------------------------------------------------------------------------------------------------------
Pressure relief device setting Maximum permitted filling density (percent by weight)
maximum start-to discharge ---------------------------------------------------------------------------------
gauge pressure in bar (psig) Carbon dioxide, refrigerated liquid Nitrous oxide, refrigerated liquid
----------------------------------------------------------------------------------------------------------------
7.2 bar (105 psig)............ 108.................................... 104
11.7 bar (170 psig)........... 105.................................... 101
16 bar (230 psig)............. 104.................................... 99
20 bar (295 psig)............. 102.................................... 97
25 bar (360 psig)............. 100.................................... 95
31 bar (450 psig)............. 98..................................... 83
37 bar (540 psig)............. 92..................................... 87
43 bar (625 psig)............. 86..................................... 80
Design service temperature -196 deg.C (-320 deg.F).............. -196 deg.C (-320 deg.F)
deg.C ( deg.F).
----------------------------------------------------------------------------------------------------------------
34. Section 173.304b would be added to read as follows:
Sec. 173.304b Additional requirements for shipment of liquefied
compressed gases in metric-marked cylinders.
(a) General requirements. Liquefied gases must be offered for
transportation, subject to the requirements in this section,
Secs. 173.301, 173.301b and 173.304, in the following metric-marked
cylinders: DOT 3M, 3FM, 3ALM, and 4M. A filling factor must be
calculated for each liquefied compressed gas to meet the following
conditions:
(1) The cylinder may not be liquid full at 55 deg.C (131 deg.F).
In addition, for a low pressure liquefied compressed gas, the vapor
space must be at least 5% of the cylinder internal volume at 50 deg.C
(122 deg.F).
(2) A cylinder with a marked test pressure greater than or equal to
35 bar (508 psi) is authorized for transportation of Division 2.1, 2.2,
and 2.3, gases Hazard Zone B, C or D gas.
(3) A DOT 3ALM, 3M, or 3FM cylinder with a marked test pressure
greater than or equal to 200 bar (2900 psi) is authorized for
transportation of a Division 2.3 Hazard Zone A gas.
(4) The pressure in a cylinder containing a high pressure liquefied
compressed gas at 65 deg.C (149 deg.F) or low pressure liquefied
compressed gas at 55 deg.C (131 deg.F) may not exceed the values in
the following table:
------------------------------------------------------------------------
Percentage of
cylinder's
Division marked test
pressure
------------------------------------------------------------------------
2.3, Zone A............................................. 63
2.3, Zone B, C.......................................... 70
2.1/5.1; 2.3, Zone D.................................... 78
2.2..................................................... 100
------------------------------------------------------------------------
[[Page 58491]]
(5) Vapor pressure may not exceed, at the maximum anticipated
temperature during transportation, the cylinder's marked test pressure.
(6) Cylinder valve and fittings must be rated at or above the
cylinder's burst pressure. The suitability of the cylinder, valve and
fitting materials must be checked, at the maximum anticipated
temperature during transportation, for operation.
(b) A DOT 3FM cylinder may not be used for a material that has a
primary or subsidiary hazard of Class 8, hydrogen sulfide or other
sulfide bearing compounds, carbon dioxide, carbon monoxide, atmospheric
gases with a dew point above -50 deg.C (-58 deg.F), or any other
material where the addition of water may make the material corrosive.
(c) A DOT 3FM or 3ALM cylinder may not be used for reclaimed
refrigerant gases.
Sec. 173.305 [Amended]
35. In Sec. 173.305, paragraph (b) would be amended by revising the
reference ``173.301(e)'' to read ``173.301a(c)''.
Sec. 173.306 [Amended]
36. In 173.306, the following changes would be made:
a. Paragraph (d)(3)(ii) would be amended by revising the reference
``Sec. 173.301'' to read ``Sec. 173.301a or Sec. 173.301b''.
b. Paragraph (g)(5) would be amended by revising the reference
``Sec. 173.301(k)'' to read ``Sec. 173.301(a)(10)''.
37. In 173.315, in paragraph (a), in Note 2 following the table,
the reference ``Sec. 173.301(d)'' would be revised to read ``paragraph
(p) of this section'' and paragraph (p) would be added to read as
follows:
Sec. 173.315 Compressed gases in cargo tanks and portable tanks.
* * * * *
(p) Manifolding is authorized for cargo tanks containing anhydrous
ammonia provided that each individual cargo tank is equipped with a
pressure relief valve or valves and gauging devices as required by
paragraphs (h) and (i) of this section. Each valve shall be tightly
closed while the cargo tank is in transit. Each cargo tank must be
filled separately.
38. Section 173.334 would be revised to read as follows:
Sec. 173.334 Organic phosphates mixed with compressed gas.
Hexaethyl tetraphosphate, parathion, tetraethyl dithio
pyrophosphate, tetraethyl pyrophosphate, or other Division 6.1 organic
phosphates (including a compound or mixture), may be mixed with a non-
flammable compressed gas. This mixture must not contain more than 20
percent by weight of organic phosphate and must be packaged in
specification 3A240, 3AA240, 3B240, 4A240, 4B240, 4BA240, or 4BW240
cylinders; or any 3M, 3FM, or 4M cylinders with a marked test pressure
of at least 25 bar (363 psig) or greater; meeting the following
requirements:
(a) Each cylinder may be filled with not more than 5 kg (11.0
pounds) of the mixture, to a maximum filling density of not more than
80 percent of the water capacity;
(b) No cylinder may be equipped with an eduction tube or a fusible
plug;
(c) No cylinder may be equipped with any valve unless the valve is
a type approved by the Associate Administrator for Hazardous Materials
Safety;
(d) Cylinders must be overpacked in a box, crate or other strong
outside packaging conforming to the requirements of Sec. 173.25 and
arranged to protect each valve or other closing device from damage.
Except as provided in paragraph (e) of this section, no more than four
cylinders may be packed in a strong outside packaging. Each strong
outside packaging with its closing device protection must be
sufficiently strong to protect all parts of each cylinder from
deformation or breakage if the completed package is dropped 1.8 m (6
feet) onto a nonyielding surface and impacted at the package's weakest
point;
(e) Cylinders may be packed in strong wooden boxes with valves or
other closing devices protected from damage, with not more than twelve
cylinders in one outside wooden box. An outer fiberboard box may be
used when not more than four such cylinders are to be shipped in one
packaging. Valves must be adequately protected. Box and valve
protection must be of strength sufficient to protect all parts of inner
packagings and valves from deformation or breakage resulting from a
drop of at least 1.8 m (6 feet) onto a nonyielding surface, impacting
at the weakest point.
39. Section 173.336 would be revised to read as follows:
Sec. 173.336 Nitrogen dioxide, liquefied, or dinitrogen tetroxide,
liquefied.
Nitrogen dioxide, liquefied, or dinitrogen tetroxide, liquefied,
must be packaged in specification cylinders as prescribed in
Sec. 173.192. Specification cylinders prescribed in Sec. 173.192 with
valve removed are authorized. Each valve opening must be closed by
means of a solid metal plug with tapered thread properly luted to
prevent leakages. Transportation in DOT 3AL and 3ALM cylinders is
authorized only by highway or rail. Each cylinder must be cleaned in
compliance with the requirements of Federal Specification RR-C-901c,
paragraphs 3.7.2 and 3.8.2. Cleaning agents equivalent to those
specified in RR-C-901b may be used; however, any cleaning agent must
not be capable of reacting with oxygen. One cylinder selected at random
from a group of 200 or less and cleaned at the same time must be tested
for oil contamination in accordance with Specification RR-C-901c
paragraph 4.4.2.3 and meet the standard of cleanliness specified
therein.
40. Section 173.337 would be revised to read as follows:
Sec. 173.337 Nitric oxide.
Nitric oxide must be packed in Specification 3A1800, 3AA1800,
3E1800, or 3AL1800 cylinders; or 3M, 3ALM, or 3FM cylinders with a
marked test pressure of 200 bar (2900 psig) or greater filled to a
pressure of not more than 52 bar (750 psi) at 21 deg.C (70 deg.F).
Cylinders must be equipped with a stainless steel valve and valve seat
which will not be deteriorated by contact with nitric oxide or nitrogen
dioxide. Cylinders or valves may not be equipped with pressure relief
devices of any type. Valve outlets must be sealed by a solid threaded
cap or plug and an inert gasketing material. In addition--
(a) Transportation in 3AL or 3ALM cylinders is authorized only by
highway or rail.
(b) Each cylinder must be cleaned in compliance with the
requirements of Federal Specification RR-C-901c, paragraphs 3.7.2 and
3.8.2. Cleaning agents equivalent to those specified in RR-C-901c may
be used; however, any cleaning agent must not be capable of reacting
with oxygen. One cylinder selected at random from a group of 200 or
less and cleaned at the same time must be tested for oil contamination
in accordance with Specification RR-C-901C paragraph 4.4.2.3 and meet
the standard of cleanliness specified therein.
PART 177--CARRIAGE BY PUBLIC HIGHWAY
41. The authority citation for Part 177 would continue to read as
follows:
Authority: 49 U.S.C. 5101-5127, 49 CFR 1.53.
42. In Sec. 177.840, paragraph (a)(1) would be revised to read as
follows:
Sec. 177.840 Class 2 (gases) materials.
* * * * *
(a) * * *
[[Page 58492]]
(1) Cylinders. Cylinders containing Class 2 (gases) materials shall
be securely lashed in an upright position, loaded in racks, or packed
in boxes or crates and securely attached to the motor vehicle to
prevent the cylinders from being shifted, overturned or ejected from
the vehicle. A cylinder containing a Class 2 material may be loaded in
a horizontal position provided that the cylinder is designed so that
the inlet to the pressure relief device is located in the vapor space
and the cylinder is properly secured and lashed.
* * * * *
PART 178--SPECIFICATIONS FOR PACKAGINGS
43. The authority citation for part 178 would continue to read as
follows:
Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.
Sec. 178.3 [Amended]
44. In Sec. 178.3, paragraph (a)(1) would be amended by removing
the wording ``DOT 4B240ET'' and adding the wording ``DOT 3M'', in its
place.
Sec. 178.35 [Amended]
45. In Sec. 178.35, the following changes would be made:
a. In paragraph (b) introductory text, the wording ``Sec. 173.300b
of this subchapter'' would be revised to read ``subpart I of part 107
of this chapter''.
b. In paragraph (b)(1), the wording ``Sec. 173.300a of this
subchapter'' would be revised to read ``subpart I of part 107 of this
chapter''.
c. In paragraph (e), the wording ``Secs. 173.34 and 173.301'' would
be revised to read ``Sec. 173.301''.
d. In paragraph (f)(2)(ii), the parenthetical wording
``(Sec. 178.44)'' and ``(Sec. 178.45)'' would be removed.
46. In addition, in Sec. 178.35, paragraph (f)(3) would be revised
to read as follows:
Sec. 178.35 General requirements for specification cylinders.
* * * * *
(f) * * *
(3) Marking exceptions. A DOT 3E cylinder is not required to be
marked with an inspector's mark or a serial number.
* * * * *
Secs. 178.36, 178.37, 178.38, 178.39, 178.45 [Removed]
47. In subpart C, Secs. 178.36, 178.37, 178.38, 178.39, and 178.45
would be removed.
48. In Sec. 178.46(a)(4), in Table 2, the entry ``6351-T6'' would
be removed and Table 1 would be revised to read as follows:
Sec. 178.46 Specification 3AL seamless aluminum cylinders.
(a) * * *
(4) * * *
Table 1.--Aluminum
[Heat or Cast Analysis for Aluminum; similar to ``Aluminum Association \1\ '' Alloy 6061 Chemical Analysis in Weight Percent \2\]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Other
------------------
Si min/max Fe max Cu min/max Mn max Mg min/max Cr min/max Zn max Ti max Pb max Bi max Each Total Al
max max
--------------------------------------------------------------------------------------------------------------------------------------------------------
0.40/0.8...................... 0.7 0.15/0.4 0.15 0.8/1.2 0.04/0.35 0.25 0.15 0.005 0.005 0.05 0.15 Bal.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The ``Aluminum Association'' refers to ``Aluminum Standards and Data 1993'', published by the Aluminum Association Inc.
\2\ Except for ``Pb'' and ``Bi'', the chemical composition corresponds with that of Table 1 of ASTM B221 for Aluminum Association alloy 6061.
* * * * *
Secs. 178.50, 178.51 and 178.55 [Removed]
49. Sections 178.50, 178.51, and 178.55 would be removed.
Sec. 178.56 [Amended]
50. In Sec. 178.56, paragraph (b) would be amended by revising the
wording ``Table 1 of Appendix A to this part'' to read ``Table 1 of
Appendix A to this subpart''.
Sec. 178.60 [Amended]
51. In Sec. 178.60, paragraph (b) would be amended by revising the
wording ``Table 1 of Appendix A to this part'' to read ``Table 1 of
Appendix A to this subpart''.
Sec. 178.61 [Removed]
52. Section 178.61 would be removed.
Sec. 178.68 [Removed]
53. Section 178.68 would be removed.
54. Section 178.69 would be added to Subpart C to read as follows:
Sec. 178.69 Applicability and design criteria for all metric-marked
DOT specification cylinders.
(a) Applicability. The definitions and general requirements
prescribed in paragraphs (b) through (g) of this section apply to the
manufacture of cylinders to the DOT 3M, 3ALM, 3FM and 4M specifications
prescribed in Secs. 178.70 through 178.81. The requirements for design
qualification tests and production tests and verifications prescribed
in paragraphs (h) and (i) of this section apply only when required by
the individual specification. All specification requirements are
minimum requirements.
(b) Definitions. For purposes of this subpart--
Associate Administrator means the Associate Administrator for
Hazardous Materials Safety.
Design qualification tests means a series of tests, including the
cycle, burst and puncture resistance test, that measure the structural
integrity of a cylinder design or significant design change.
Heat treatment means heating and cooling a solid metal or alloy in
such a way as to obtain desired conditions or properties. In addition:
(1) Quench and temper heat treatment means the process of heat
treating and cooling cylinders by liquid quenching. The liquid must
have a cooling rate of less than 80 percent of that of water. The
temperature on quenching shall be appropriate for the material of
construction but may not exceed 957 deg.C (1750 deg.F).
(2) Normalizing heat treatment means heating a ferrous alloy to a
suitable temperature above its transformation temperature, not to
exceed 957 deg.C (1750 deg.F), and then cooling it in air to ambient
temperature.
(3) Annealing heat treatment means heating to and holding at a
suitable temperature and then cooling to facilitate cold working.
(4) Stress relieving heat treatment means heating to a suitable
temperature, holding long enough to reduce residual stresses and then
cooling slowly enough to minimize the development of new residual
stresses.
Lot means a group of cylinders successively produced in a work
shift of not more than 10 hours of continuous operation having--
(1) The same specified size and configuration, within the
parameters of ``significant change'' to an original design as defined
in this section;
(2) The same specified material of construction (i.e. cast or
heat);
(3) The same process of manufacture; and
[[Page 58493]]
(4) Been subjected to similar conditions of time, temperature,
cooling rate, and atmosphere during heat treatment.
Plugged cylinder is a cylinder with a permanent end closure
achieved by the insertion of a threaded plug.
Proof pressure test means a pressure test by interior
pressurization without the determination of the cylinder's expansion.
Settled pressure, (formerly referred to as service pressure) means
the pressure of the contents of the cylinder at 15 deg.C (59 deg.F).
Significant change to an original design means--
(1) A 10 percent or greater change in cylinder wall thickness, test
pressure or diameter;
(2) A 30 percent or greater change in water capacity or base
thickness;
(3) Any change in specified material;
(4) An increase in the diameter of openings of over 100 percent; or
(5) Any change in the number of openings.
Spun cylinder is a cylinder with an end closure that has been
welded by the spinning process.
Volumetric expansion test means a pressure test by interior
pressurization to measure a cylinder's expansion by using the water
jacket or direct expansion methods.
(1) Water jacket method means a volumetric expansion test to
determine a cylinder's total and permanent expansion by measuring the
difference between the volume of water the cylinder externally
displaces at test pressure and the volume of water the cylinder
externally displaces at ambient pressure
(2) Direct expansion method means a volumetric expansion test to
calculate a cylinder's total and permanent expansion by measuring the
amount of water forced into a cylinder at test pressure, adjusted for
the compressibility of water, as a means of determining the expansion.
(c) Inspection and analyses. Inspection and analyses must be in
compliance with the following:
(1) Inspections and verifications, as required, must be performed
by a hazmat employee of an independent inspection agency that has been
approved in writing by the Associate Administrator in accordance with
Sec. 107.803 of this chapter.
(2) Chemical analyses and tests must be made in the United States
or at a facility located outside the United States that is approved in
writing by the Associate Administrator in accordance with Sec. 107.807
of this chapter and under the supervision of an independent inspection
agency approved under Sec. 107.803 of this chapter.
(d) Authorized material and material identification. (1) Material
of construction must be of uniform quality.
(2) Materials with seams, cracks, laminations or other defects
likely to weaken the finished cylinder may not be used.
(3) Materials must be identified with the heat or cast code by a
suitable method during manufacture. If the heat or cast identification
is permanently stamped on the cylinder, it must be stamped in an area
other than the sidewall of the cylinder.
(e) Duties of the inspector. The inspector shall determine that
each cylinder conforms to the requirements in this section and the
applicable individual specification. In making these determinations,
the inspector shall:
(1) Verify that all procedures for obtaining and reporting the
chemical analysis are in accordance with the appropriate requirements
of ASTM Chemical Analysis Test Methods and that the chemical analysis
is in conformance with the individual specification by--
(i) Obtaining a certified cast or heat analysis from the material
producer, supplier, or from the cylinder manufacturer, for each heat or
cast of material; or
(ii) Peforming or obtaining a check (solid metal) analysis, when
such check analysis is required;
(2) Witness that the applicable design qualification tests
prescribed in paragraph (h) of this section for each new cylinder
design or a significant change to an original design have been
performed with satisfactory results;
(3) Select samples for all tests;
(4) Select samples for the check analysis, when performed;
(5) Verify that identification of material is proper;
(6) Verify that the manufacturer makes a complete internal
inspection of the cylinder body before closing the ends;
(7) Verify that wall thickness was measured and that the specified
minimum thickness is met;
(8) Verify that the heat treatment is proper;
(9) Witness each test (except that results of the hardness test and
the grain size test may be verified);
(10) Verify by gauge that threads are in conformance with the
specification;
(11) Verify that each cylinder is marked in accordance with the
applicable specification;
(12) Verify that gauges and test equipment are properly calibrated;
(13) Prepare a report containing, at a minimum, the information
required by the applicable provisions of this subpart and the
information listed in CGA Pamphlet C-11 and provide the report to the
manufacturer and, upon request, to the purchaser. The inspector must
retain the reports required by this section and the applicable
individual specification for 15 years from the original test date on
the cylinder. Each report must be legible and in English; and
(14) Certify that all cylinders represented by the test report meet
all applicable requirements of the specification through inspection,
verification, or any other action required to assure compliance.
(f) Threads. Threads must conform to the following:
(1) Each thread must be clean cut, even, without checks and to
gauge.
(2) Taper threads must conform to one of the following--
(i) American Standard Pipe Thread (NPT) type must conform to the
requirements of Federal Standard H-28, Section 7 (FED-STD-H28/7A);
(ii) National Gas Taper thread (NGT) type must conform to the
requirements of Federal Standard H-28 Sections 7 (FED-STD-H28/7A), and
9 (FED-STD-H28/9A);
(iii) Other taper threads conforming to other standards may be used
provided the total thread shear strength is not less than that
specified for NPT threads.
(3) Straight threads must conform to one of the following--
(i) National Gas Straight Thread (NGS) type must conform to the
requirements of Federal Standard H-28, Sections 7 (FED-STD-H28/7A), and
Section 9 (FED-STD-H28/9A);
(ii) Unified Thread (UN) type must conform to the requirements of
Federal Standard H-28, Section 2 (FED-STD-H28/2B);
(iii) Controlled Radius Root Thread (UNJ) type must conform to the
requirements of Federal Standard H-28, Section 4 (FED-STD-H28/4);
(iv) Other straight thread types conforming to other standards may
be used provided the requirements of paragraph (f)(4) of this section
are met.
(4) All straight threads must have at least 4 engaged threads, a
tight fit, and calculated shear strength of at least 10 times the shear
stress at the test pressure of the cylinder. Shear strength must be
calculated by using the appropriate thread shear area in accordance
with Federal Standard H-28 Section 2, Appendix B (FED-STD-H28/2B
Appendix B). Gaskets are required to prevent leakage.
[[Page 58494]]
(g) Pressure relief devices and protection for valves, pressure
relief devices, fittings and connections. (1) Pressure relief devices
on cylinders must conform to the requirements of Sec. 173.301(f) of
this subchapter.
(2) Protection for valves, pressure relief devices, fittings and
connections must conform to the requirements of Sec. 173.301(h)(2) of
this subchapter.
(h) Design qualification tests. Each cylinder design and each
cylinder design having a ``significant change'' from the original
design must be subjected to the design qualification tests prescribed
in this paragraph (h).
(1) Cycle test. The cycle test must be performed on a cylinder
after it has passed the volumetric expansion test, by subjecting it to
successive hydraulic pressurization and depressurization cycles. The
rate of cycling may not exceed 10 cycles per minute.
(i) The lower cyclic pressure may not exceed 10 percent of the
upper cyclic pressure. The upper cyclic pressure must be at least equal
to the prescribed minimum test pressure.
(ii) The test cylinder must be subjected to a pressure exceeding 90
percent of the upper cyclic pressure for at least 20 percent of the
duration of each cycle.
(iii) The cycle test must be performed on at least three
representative samples of each design or any significant change to an
original design.
(iv) All cylinders used in the cycle test must be rendered
incapable of holding pressure following completion of the cycle test.
(2) Burst test. The burst test must be performed on a
representative completed cylinder selected at random after heat
treatment by hydraulically pressurizing the cylinder to failure. The
rate of pressurization may not exceed 14 bar (200 psi) per second.
Burst testing of each design or any significant change to a previously
tested design must be performed on at least 3 representative cylinders.
(3) Puncture resistance test. Each cylinder design type intended
for the transportation of Division 2.3 gases or Division 6.1 liquids in
Hazard Zones A and B must pass the following test. Cylinders that are
shipped in an overpack must be tested in the overpack.
(i) The puncture resistance test must be performed on three
representative cylinders selected at random after heat treatment. The
cylinder must be filled with water and pressurized to \2/3\ the marked
test pressure at 21 deg. C (70 deg. F). The cylinder must be tested on
its sidewall, supported on an unyielding support and tied down so that
there is no movement during impact. The puncturing probe must consist
of a 2 inch x 2 inch x \1/4\ inch angle iron, its end sawed off at
90 deg. to form a sharp corner. The probe must have a weight attached
that is equivalent to the weight of the cylinder including the heaviest
material to be shipped. The probe must be dropped from a minimum height
of 2.1m (7 feet) from the top surface of the cylinder, perpendicular to
the cylinder's longitudinal centerline, and must impact the cylinder
sidewall on the top of the cylinder. The sharp corner of the angle iron
must impact the centerline of the cylinder. (See Figure 1 of this
section.)
(ii) There must be no leakage as a result of the impact. The
cylinder must be leak tested, using compressed gas charged to 2/3 of
the marked test pressure.
(4) Acceptable test results. Acceptable design qualification test
results are as prescribed in the individual cylinder specification.
(i) Production tests and verifications. When the individual
specification requires a particular production test to be performed,
the test must be conducted on the finished cylinder as prescribed in
this paragraph (i). Unless otherwise noted in this section, acceptable
test results are prescribed in the individual cylinder specification.
Any lot not meeting acceptable test results must be rejected:
(1) Flattening or bend test. Flattening or bend tests must be
performed, on a representative completed cylinder selected at random
or, if authorized by the individual specification on a test ring, after
heat treatment. Each test ring used for the test must meet the
requirements of paragraph (i)(7) of this section.
(i) During the flattening test, the cylinder or test ring must be
flattened between wedge-shaped knife edges with the longitudinal axis
of the cylinder at approximately 90 degrees to the knife edges. For
steel and nickel cylinders, the knife edges must have a 60 degree
included angle and be rounded to a 13 mm (1/2 inch) radius. For
aluminum cylinders, see Sec. 178.72(i)(4).
(ii) A bend test in accordance with ASTM E 290 may be substituted
for the flattening test. Two test pieces cut from a sidewall ring or
rings shall be tested. The width shall be the greater of 25 mm (1 inch)
or four times the thickness of the test specimen. A load shall be
applied to the inside surface of the test piece by a mandrel at the
mid-length until the interior edges are no further apart than the
mandrel diameter. For steel cylinders the mandrel shall not be greater
than four times the actual wall thickness.
(iii) For a cylinder with a water capacity of 454 kg (1,000 pounds)
or less, the flattening or bend test must be performed on a cylinder
selected from each lot.
(iv) For a cylinder with a water capacity exceeding 454 kg (1,000
pounds), the flattening or bend test must be performed on a cylinder or
on a test ring out of each lot when cylinders are heat treated in a
batch furnace, or from one cylinder or test ring out of each four hours
or less of production when the cylinders are heat treated in a
continuous furnace.
(v) A retest using one additional set of specimens is authorized if
a test was considered improper due to the presence of a fault in the
equipment or specimen preparation. Retest specimens must be taken from
this same cylinder if space permits or from another randomly selected
cylinder in the same lot.
(2) Grain size. For cylinders made from nickel, preparation and
examination of the specimen and grain size calculation must be as
prescribed in ASTM E 112.
(3) Hardness test. Apparatus and procedures must be in conformance
with ASTM E 18 for Rockwell C scale (HRC) hardness number or ASTM E 10
for Brinell hardness number (HBS).
(4) Impact test. The impact test must be performed on specimens
taken from the cylinder or, if authorized by the individual
specification, from a test ring, after heat treatment. Each test ring
used for the test must meet the requirements of paragraph (i)(7) of
this section. Impact specimens must be prepared and tested in
accordance with ASTM E 23 and the specific requirements in the
individual specification. A cylinder or a test ring need represent only
one of the heats in the lot, provided the other heats in the lot were
heat treated under the same conditions and have previously been tested
and have passed the tests.
(i) For a cylinder with a water capacity of 454 kg (1,000 pounds)
or less, the specimens must be taken from one cylinder or test ring out
of each lot.
(ii) For a cylinder with a water capacity exceeding 454 kg (1,000
pounds), the specimens must be taken from one cylinder or test ring out
of each batch when cylinders are heat treated in a batch furnace, or
from one cylinder or test ring out of each 4 hours or less of
production when cylinders are heat treated in a continuous furnace.
(5) Leakage test. Spun cylinders must be tested for leakage by
subjecting the inside of the finished bottom to a
[[Page 58495]]
pressure of not less than \1/2\ of the cylinder's marked test pressure.
The bottom must be clean and free from all moisture. Pressure must be
applied, using dry gas, over an area of at least six percent of the
total area of the bottom but not less than 19 mm (\3/4\ inch) in
diameter including the closure. The required pressure must be applied
for at least one minute, during which time the outside of the bottom
under test must be covered with water or other suitable leak detecting
fluid and closely examined for indication of leakage. The leakage test
must be performed prior to the closing of the cylinder. The cylinder
may not show any evidence of leakage.
(6) Magnetic particle and liquid penetrant examinations. The
apparatus and procedures for the magnetic particle examination, wet or
dry method, must conform to ASTM E 709. The apparatus and procedures
for the liquid penetrant inspection must conform to ASTM E 165.
(7) Mechanical tests. Unless otherwise specified in the individual
cylinder specification, a mechanical test must be performed on a
minimum of two specimens taken at least 160 degrees apart from a
representative completed cylinder which is selected at random after
pressure testing and heat treatment. For cylinders more than 2 meters
(6.5 feet) long, the mechanical test may be performed on a test ring
which has been heat treated with the completed cylinders. The test ring
must be at least 61 cm (24 inches) long and must have its ends covered
during heat treatment so as to simulate the heat treatment process of
the finished cylinder it represents. Each test ring used for the test
must be of the same specification material, diameter and thickness as
the finished cylinder it represents. A test cylinder or test ring need
represent only one of the heats in the lot provided the other heats in
the lot have previously been tested and have passed the tests.
(i) Specimens must conform to the following:
(A) The long axis of the specimen must be parallel to the
longitudinal axis of the cylinder.
(B) The tensile specimen reduced section may not be flattened.
However, the grip ends may be flattened to within 25 mm (1 inch) of
each end of the reduced section.
(C) Temperatures generated during the preparation of a specimen may
not exceed 204 deg.C (400 deg.F) for steel or nickel, or 121 deg.C
(250 deg.F) for aluminum.
(ii) The tensile strength, yield strength, and elongation of the
material must be determined as follows:
(A) The yield strength in tension must be the stress corresponding
to a permanent strain of 0.2 percent of the gauge length.
(B) For steel and nickel, the yield strength must be determined by
the ``offset'' method or the extension under-load method described in
ASTM E 8. For aluminum material, the yield strength must be determined
by the ``offset'' method or the extension under load method as
described in ASTM B 557.
(C) The cross-head speed of the testing machine may not exceed 3 mm
(\1/8\ inch) per minute during the determination of yield strength,
however, any test speed may be used until one-quarter of the specified
tensile strength is reached.
(D) The specimens must be taken from one cylinder selected from
each lot.
(E) When the length of the cylinder does not permit securing
straight specimens, then specimens may be taken in any location or
direction and may be straightened or flattened cold, by pressure only,
not by blows. The inspector's report must indicate that the specimens
were taken and prepared in this manner.
(F) The size of the specimen must be one of the following--
(1) gauge length of 50 mm (2 inches) and a maximum width of 38 mm
(1.5 inches);
(2) gauge length of 200 mm (8 inches) and a maximum width of 38 mm
(1.5 inches); or
(3) gauge length of at least 24 times specimen actual thickness and
a maximum width of 6 times actual thickness, provided that the cylinder
wall is not over 4.7 mm (\3/16\ inch) thick.
(G) For a cylinder with a water capacity exceeding 454 kg (1,000
pounds):
(1) The specimens must be taken from one cylinder or test ring out
of each batch when cylinders are heat treated in a batch furnace or
from one cylinder or test ring out of each 4 hours or less of
production when cylinders are heat treated in a continuous furnace.
(2) The size of the specimen must be as prescribed in the
individual specification.
(iii) A retest using one additional set of specimens is authorized
if a test was considered improper due to a fault in the equipment or
specimen preparation. Retest specimens must be from the same cylinder
if space permits, or from another randomly selected cylinder from the
same lot.
(8) Mechanical tests of welds. (i) Tensile test: Specimens must be
prepared in accordance with and meet the requirements of CGA Pamphlet
C-3. Should any specimen from the first test fail to meet the
requirements, a second test may be performed taken from three
additional cylinders selected at random from the same lot. If either of
the additional specimens fails to meet the requirements of CGA Pamphlet
C-3, the entire lot must be rejected.
(ii) Guided bend test: Specimens must be prepared in accordance
with and meet the requirements of CGA Pamphlet C-3.
(iii) Alternate guided-bend test: This test may be used as an
alternative to the guided bend test specified in paragraph (i)(8)(ii)
of this section and must be performed in accordance with CGA Pamphlet
C-3. The specimen shall be bent until the elongation at the outer
surface, adjacent to the root of the weld, between the lightly scribed
gauge lines--``a'' to ``b'', shall be at least 20 percent, except that
this percentage may be reduced for steels having a tensile strength in
excess of 340 MPa (50,000 psi), as provided in table 4 of Sec. 178.81.
(9) Production burst test. When required by a particular
specification, must be performed on at least one cylinder from each
lot. A cylinder used in the cycle test may be used for the production
burst test. If a cylinder fails the production burst test, a second
sample of three cylinders from the same lot must be selected by the
independent inspector. If any of these tested cylinders fail, the lot
must be rejected.
(10) Proof pressure test. The pressure for the proof pressure test
must be at least equal to the marked test pressure and must be
maintained for at least ten seconds, and sufficiently longer, as
necessary, to assure there is no leakage and no drop in pressure. The
cylinder may show no evidence of leakage or distortion.
(11) Radiographic examination. Radiographic examination of
cylinders must conform to the techniques and acceptability criteria set
forth in CGA Pamphlet C-3. When fluoroscopic examination is used,
permanent film records need not be retained.
(12) Ultrasonic examination. The ultrasonic examination must be
performed on the cylindrical section of the completed cylinder after it
has passed the volumetric expansion test. Testing must be in accordance
with Appendix B of this subpart.
(13) Volumetric expansion test. After heat treatment, each cylinder
must be subjected to an internal pressure at least equal to the marked
test pressure. The water jacket method must be performed in accordance
with paragraph 4 and Appendices A and B of CGA Pamphlet C-1. An
alternative test procedure, such as direct expansion, may be used when
[[Page 58496]]
approved in writing by the Associate Administrator. If the required
test pressure can not be maintained due to failure of test apparatus,
the cylinder must be rejected or the test must be repeated at a
pressure increased by 10 percent of the test pressure or 7 bar (100
psi) whichever is lower. Only two retests are authorized. The permanent
expansion measured at zero gauge pressure may not exceed 10 percent of
the total measured expansion at test pressure.
(j) Rejected cylinders. When a lot of cylinders is rejected, and
reheat treatment may correct the cause of rejection, the lot may be
reheat treated and retested as if it were a new lot.
(1) Volumetric expansion test: Reheat treatment of rejected
cylinders that failed due to excessive permanent expansion is
authorized.
(2) Magnetic particle, liquid penetrant and ultrasonic
examinations: Any cylinder rejected because of cracks may not be
requalified.
(k) Markings. Required markings on the cylinder must be in
accordance with the following:
(1) Each cylinder must be legibly and permanently marked by
stamping on the shoulder, top head or neck. The depth of marking must
ensure that the wall thickness measured from the root of the stamping
to the interior surface is equal to or greater than the prescribed
minimum wall thickness.
(2) For a DOT-4M specification cylinder the required markings must
be stamped plainly and permanently on the shoulders, top head, neck,
valve boss, valve protection sleeve, collar, or similar part
permanently attached to the top of the cylinder. For cylinders that do
not exceed 11.3 kg (25 pounds) water capacity, the marking may be on
the footring permanently attached to the cylinder.
(3) The required markings specified in this paragraph (k) (3) must
be stamped on the cylinder in the sequence shown in items 1 through 12,
with no additional information interspersed, as illustrated in the
following example:
DOT-3M/USA/M1234/SN123456/UT/200BAR/IA01/98-09/250/5.8/SS/56.5
Where:
1. DOT 3M = DOT specification number.
2. USA = country of manufacture.
3. M1234 = symbol of manufacturer assigned by the Associate
Administrator.
4. SN123456 = manufacturer's serial number.
5. UT = stamp for non-destructive ultrasonic examination, if
applicable.
6. 200BAR = test pressure (bar).
7. IA01 = Independent Inspection mark.
8. 98-09 = date of test (year and month).
9. 250 = water capacity (liters).
10. 5.8 = minimum guaranteed wall thickness (millimeters).
11. SS = identification of alloy (SS:stainless steel, NI:Nickel, AL:
Aluminum CS: Carbon Steel).
12. 56.5 = tare weight (kilograms).
(4) Required markings must be at least 6 mm (0.250 inch) high,
except that cylinders having an inside diameter less than 102 mm (4
inches) may have markings that are at least 3 mm (0.116 inch) high.
(5) Stamping on the side wall is prohibited.
(6) No other markings may conflict with the required markings.
(7) Other variations in stamping required marks is authorized only
when necessitated by lack of space or as approved in writing by the
Associate Administrator.
(l) Coatings. Coatings on a cylinder's exterior or interior walls
are authorized, except that the coating must not cause markings to be
illegible, obscure defects, or allow moisture to be trapped between the
cylinder wall and the coating. Any coating that may prevent adequate
visual inspection or ultrasonic examination is prohibited.
BILLING CODE 4910-60-P
[[Page 58497]]
Figure 1 to Sec. 178.69
[GRAPHIC] [TIFF OMITTED] TP30OC98.000
[[Page 58498]]
55. Section 178.70 would be added to Subpart C to read as follows:
Sec. 178.70 General requirements for DOT 3 series metric-marked
seamless cylinders.
(a) DOT specifications 3M (Sec. 178.71), 3ALM (Sec. 178.72), and
3FM (Sec. 178.73) cylinders must meet the requirements contained in
this section, Sec. 178.69, and the requirements of the applicable
individual specification contained in Secs. 178.71 through 178.73.
(b) Lot size. In no case may a lot exceed 200 cylinders, but any
cylinder processed for use in the required destructive testing need not
be counted as being one of the 200.
(c) Authorized material and identification of material. All tubing,
billet, sheet, plate or cast stock must be in conformance with one of
the specifications in Table 1 or 2 of Appendix A of this subpart. The
inspector may require a check analysis to establish the heat or cast
analysis when necessary to meet the requirements of Sec. 178.69(c)(2).
The material may not be used if the results of such analysis indicates
nonconformance with the requirements of the material specification.
(d) Manufacture. (1) Each cylinder must be of seamless construction
with integrally formed heads and bottoms.
(2) The manufacturing process must be capable of producing a
cylinder that is free from defects likely to weaken the finished
cylinder. For a cylinder with a water capacity of more than 454 kg
(1000 pounds), permanent closures formed by spinning are prohibited and
integral heads must be concave to pressure.
(3) Dirt and scale must be removed to permit proper inspection.
Each cylinder must have a smooth and uniform finish. Fissures, laps,
tears, or other defects that are likely to weaken the finished cylinder
are not acceptable. The thickness of the treated areas must be measured
and may not be less than the prescribed minimum sidewall thickness.
Machining or other treatment of the cylinder to eliminate defects must
be completed before heat treatment and volumetric expansion testing.
(4) Head and bottom configurations must be as follows:
(i) Bottoms of bumped-back cylinders must have a minimum thickness
of not less than two times the prescribed minimum sidewall thickness.
Such bottom thickness must be measured within an area bounded by a line
representing the points of contact between the cylinder and the floor
when the cylinder is in a vertical position.
(ii) For heads and bottoms concave to pressure, the inside shape
must be hemispherical, ellipsoidal, or torispherical with a major to
minor axis not exceeding 2 to 1, or a dished shape falling within these
limits. Such heads and bottoms must be at least the prescribed minimum
wall thickness of the cylindrical shell, except as follows:
(A) The thickness at the point of closure of spun cylinders must be
at least 2 times the prescribed minimum sidewall thickness.
(B) The thickness of the hemispherical bottoms on cylinders formed
from sheet or plate must be at least 90 percent of the prescribed
minimum sidewall thickness.
(5) Welding or brazing for any purpose is prohibited on cylinders
manufactured in accordance with this section.
(6) Plugged cylinders are not authorized.
(e) Wall thickness. The following requirements apply:
(1) The minimum wall thickness for a cylinder must be the greater
of the thickness as determined by this paragraph (e), or as required by
the individual specification.
(2) For the minimum wall thickness calculations, the following
formula must be used:
S = [P(1.3D2+0.4d2)]/
(D2-d2)
Where:
S = Wall stress in Mpa (psi).
P = Minimum test pressure in bar (psi), as prescribed for the
volumetric expansion test, but not less than 31 bar (450 psi).
D = Outside diameter in mm (inches).
d = Inside diameter in mm (inches).
(3) A steel cylinder longer than 2 meters (6.5 feet) must meet the
following additional requirements if the cylinder is horizontally
supported at its two ends. The load of the cylinder consists of the
weight per unit length, in newtons per millimeter, of the cylindrical
portion filled with water and pressurized to the prescribed minimum
test pressure. The wall thickness must be increased when necessary to
meet the following requirements:
(i) The sum of 2 times the maximum tensile stress at the mid-point
of the unsupported length, due to bending (see paragraph (e)(3)(ii) of
this section), plus the maximum longitudinal stress in the same area,
due to the hydrostatic pressure (see paragraph (e)(3)(iii) of this
section), may not exceed 80 percent of the minimum yield strength of
the steel as determined by the mechanical tests prescribed in
Sec. 178.69(i)(7) and the applicable individual specification.
(ii) The following formula must be used to calculate the maximum
tensile stress due to bending--
S = MC/I
Where:
S = tensile stress in MPa.
M = bending moment in newton-mm = .125Wl2.
C=radius (D/2) of cylinder in mm.
I=Moment of inertia=.04909 (D4-d4) in
mm4.
W=weight in newtons per mm of cylinder length full of water.
l=length of cylinder in mm.
D=outside diameter in mm.
d=inside diameter in mm.
(iii) The following formula must be used to calculate the maximum
longitudinal tensile stress due to volumetric expansion test pressure--
S(MPa)=[A1P/10A2]
Where:
S=tensile strength in MPa.
A1=internal area in cross section of the cylinder in
mm2.
A2=area of metal in cross section of the cylinder in
mm2.
P=volumetric expansion test pressure in bar.
(f) Openings. Openings are not permitted on the side wall and must
be centered on the heads. Openings may not exceed the smaller of one-
half of the cylinder's outside diameter or 200 mm (8 inches). All
openings must be circular and threaded.
(g) Heat treatment. After forming, cylinders must be uniformly and
properly heat treated under similar conditions of time, temperature,
cooling rate and atmosphere prior to all tests. The furnace temperature
must be controlled to assure a uniform process and have sufficient
instrumentation to control performance.
56. Section 178.71 would be added to Subpart C to read as follows:
Sec. 178.71 Specification 3M; seamless steel, nickel and stainless
steel metric-marked cylinders.
(a) General requirements and test pressure. Each DOT specification
3M cylinder must meet the general requirements contained in
Secs. 178.69 and 178.70 and the specific requirements contained in this
section. The design test pressure must be no less than 15 bar (218
psi).
(b) Duties of the inspector. In addition to the duties prescribed
in Sec. 178.69(e), an inspector must verify that the grain size in a 3M
cylinder manufactured from nickel is in accordance with paragraph
(h)(6) of this section.
(c) Authorized materials and identification of materials. Materials
must be in accordance with the following:
(1) All tubing, billet, sheet, plate or cast stock must be in
conformance with
[[Page 58499]]
Grade A, C, or D material specified in Table 1 of Appendix A of this
subpart.
(i) Grade A material is authorized for steel cylinders.
(ii) Grade C material is authorized for stainless steel cylinders.
(iii) Grade D material is authorized for nickel cylinders.
(d) Manufacture. Spun closures for nickel cylinders are prohibited.
(e) Wall thickness. (1) For cylinders with a test pressure less
than 93 bar (1350 psi), the minimum wall must be such that the wall
stress at the prescribed minimum test pressure does not exceed 165 MPa
(24,000 psi) for cylinders made from Grade A or C material and in no
case may the wall thickness be less than 2mm (.078 inch).
(2) For cylinders with a test pressure of 93 bar (1350 psi) or
more, the minimum wall must be such that the wall stress at the
prescribed minimum test pressure does not exceed the following:
(i) 380 MPa (55,000 psi) for cylinders made from Grade A material;
(ii) 235 MPa (34,000 psi) for cylinders made from Grade C material.
(3) For cylinders made from Grade D material, the minimum wall must
be such that the wall stress at the prescribed minimum test pressure
does not exceed 100 MPa (15,000 psi), or 50 percent of the minimum
tensile strength as determined by the mechanical properties tests
prescribed in Sec. 178.69(i)(7).
(f) Heat treatment. A cylinder made from:
(1) Grade A material must be heat treated by normalizing at a metal
temperature most suitable for the material, and air cooled. Liquid
quenching is not authorized. Intermediate manganese steel may be given
a quench and temper heat treatment.
(2) Grade C material does not require heat treatment.
(3) Grade D material does not require heat treatment. If the
cylinder is heat treated, the furnace atmosphere during heat treatment
must be sulfur-free and neutral or reducing.
(g) Design qualification tests. The following design qualification
tests described in Sec. 178.69 apply:
(1) Cycle test. Cylinders representative of the design must
withstand, without distortion or failure, at least 10,000
pressurizations.
(2) Burst test. Representative cylinders of each design must meet
the following--
(i) For nickel cylinders the test cylinders must withstand at least
2 times test pressure.
(ii) For steel cylinders the test cylinders must withstand at least
1.6 times test pressure.
(h) Production tests and verification. The following examinations
and tests apply. Unless otherwise noted in this section, acceptable
results are prescribed in Sec. 178.69.
(1) Volumetric expansion test.
(2) Leakage test for spun cylinder.
(3) Ultrasonic examination in accordance with ASTM E 213 for
measurement of sidewall defects: Any cylinder having a discontinuity
greater than two times in length and 10 percent in depth of the
designed minimum wall thickness or any discontinuity greater than 15%
of the minimum designed wall thickness in depth must be rejected.
(4) Mechanical test: The yield strength may not exceed 73 percent
of the tensile strength for steel cylinders, or 50 percent of the
tensile strength for nickel cylinders. Elongation must be at least 20
percent for a 50mm (2-inch) gauge length specimen or at least 10
percent in other cases. In this instance, a flattening test or bend
test is required. If elongation is at least 40 percent for the 50mm (2-
inch) gauge length specimen, or at least 20 percent in other cases, a
flattening test or bend test is not required.
(5) Flattening or bend test: Steel cylinders must withstand
flattening to six times wall thickness without cracking; nickel
cylinders must withstand flattening to four times wall thickness
without cracking. Bend test specimens must be free of cracking when
deformed around a mandrel not greater in diameter than 4 times the wall
thickness for steel or 2 times the wall thickness for nickel.
(6) Grain size verification: For nickel cylinders, a specimen must
be taken from the sidewall of a representative cylinder from each lot.
The diameter of the average grain cross section may not exceed 0.065 mm
(0.0026 inch). The corresponding ASTM micro-grain size number is 5.0.
When the grain size in the test cylinder exceeds this limit, the lot
must be rejected.
(7) Magnetic particle or liquid penetrant examination: Magnetic
particle or liquid penetrant inspection must be performed on each
cylinder constructed of intermediate manganese steel after heat
treatment to determine the presence of quenching cracks. Cracked
cylinders must be rejected.
(i) Rejected cylinders. Nickel cylinders, rejected for unacceptable
grain size, may be reheat treated. Thereafter, the reheat treated
cylinders must pass all prescribed tests including verification of
acceptable grain size.
57. Section 178.72 would be added to Subpart C to read as follows:
Sec. 178.72 Specification 3ALM; seamless aluminum metric-marked
cylinders.
(a) General requirements. Each DOT Specification 3ALM seamless
aluminum cylinder must meet the general requirements contained in
Secs. 178.69, 178.70 and the specific requirements contained in this
section.
(b) Capacity. The water capacity may not exceed 454 kg (1,000
pounds).
(c) Duties of the inspector. In addition to the duties prescribed
in Sec. 178.69(e), the inspector must verify compliance with the
provisions in paragraph (d) of this section, either by inspection or by
obtaining the material manufacturer's certificate of inspection.
(d) Authorized material and identification of materials. Only the
aluminum alloy specified in Table 2 of Appendix A to this subpart is
authorized. Material must be identified with the heat or cast code by a
suitable method that will identify the alloy. Cast stock must have
uniform isotropic grain structure not to exceed 500 microns maximum.
(e) Manufacture. Only the extrusion process is authorized. Closures
formed by spinning are prohibited. The cylinder bottom must be concave
to pressure. The thickness of the cylinder base may not be less than
the side wall thickness. The bottom of the cylinder must have an inside
shape that is torispherical, hemispherical or ellipsoidal, where the
dish radius is no greater than 1.2 times the inside diameter of the
shell. The knuckle radius may not be less than 12 percent of the inside
diameter of the shell. The interior base contour may deviate from the
true torispherical, hemispherical or ellipsoidal configuration,
provided that--
(1) Any area of deviation is accompanied by an increase in base
thickness;
(2) All radii of merging surfaces are equal to or greater than the
knuckle radius; and
(3) Each design has been qualified by successfully passing the
cycling and burst tests specified in paragraph (h) of this section.
(f) Wall thickness. The minimum wall thickness must be such that
the wall stress at the prescribed minimum test pressure does not exceed
80 percent of the minimum yield strength nor 67 percent of the minimum
tensile strength of the cylinder material as determined by the
mechanical properties tests prescribed in Sec. 178.69(i)(7), but in no
case may the minimum wall thickness be less than 4mm (0.156 inch).
[[Page 58500]]
(g) Heat treatment. Prior to any test, each cylinder must be
subjected to a solution heat treatment and aging treatment appropriate
for the type of aluminum used.
(h) Design qualification tests. The following design qualification
tests described in Sec. 178.69 apply:
(1) Cycle test. Cylinders representative of the design must
withstand, without distortion or failure, at least 10,000
pressurizations to the prescribed minimum test pressure.
(2) Burst test. Cylinders representative of the design, must have a
minimum burst of 1.6 times test pressure.
(i) Production tests and verifications. The following examinations
and tests apply. Unless otherwise noted in this section, acceptable
results are prescribed in Sec. 178.69.
(1) Volumetric expansion test.
(2) Ultrasonic examination. The examination must be performed in
accordance with ASTM E 213 for measurement of sidewall defects. Any
cylinder having a discontinuity greater than two times in length and 5
percent in depth of the design minimum wall thickness must be rejected.
(3) Mechanical tests. Mechanical tests must be performed as
follows: The two tensile specimens must be one of the following: Flat
specimen, 50 mm (2-inch) gauge length; Flat specimen, 24t gauge length
by 6t width; or Round specimen, 4D gauge length with diameter ``D''.
When the cylinder sidewall is greater than 5 mm (\3/16\-inch), a retest
without reheat treatment using this ``4D'' specimen is authorized if
the test using the 2-inch specimen fails to meet elongation
requirements. The 4D specimen must meet requirements of ASTM E 8.
Tensile strength must be at least 260 Mpa (38000 psi). Yield strength
must be at least 240 Mpa (35,000 psi). Elongation must be at least 14
percent for 50 mm (2-inch) gauge length specimen, at least 10 percent
for 24t by 6t specimen, and at least 14 percent for the ``4D''
specimen.
(4) Flattening and bend test. A flattening or bend test must be
performed as follows:
(i) The flattening test must be performed by placing the test
cylinder between wedge-shaped knife edges having a 60 degree included
angle, and rounded in accordance with the following table. The
longitudinal axis of the cylinders must be at an angle of 90 degrees to
the knife edges during the test. The test cylinder must withstand
flattening to 9 times wall thickness without cracking. The table
follows:
Table.--Flattening Test
------------------------------------------------------------------------
Rounded
Cylinder wall thicknesses (inches) radius
(inches)
------------------------------------------------------------------------
Under 0.150................................................ 0.500
0.150 to 0.249............................................. 0.875
0.250 to 0.349............................................. 1.500
0.350 to 0.449............................................. 2.125
0.450 to 0.549............................................. 2.750
0.550 to 0.649............................................. 3.500
0.650 to 0.749............................................. 4.125
------------------------------------------------------------------------
(ii) An alternate bend test, in accordance with ASTM E 290 using a
mandrel diameter not more than 6 times the wall thickness, is
authorized. This test may be used to qualify a lot that has failed the
flattening test. Reheat treatment is not required for this test. If
used, this test must be performed on 2 samples from one cylinder taken
at random out of each production lot. The test specimens shall remain
uncracked when bent inward around a mandrel in the direction of
curvature of the cylinder wall, until the interior edges are at a
distance apart not greater than the diameter of the mandrel.
58. Section 178.73 would be added to Subpart C to read as follows:
Sec. 178.73 Specification for DOT 3FM; seamless steel metric-marked
cylinders.
The construction of a cylinder to this specification also meets the
requirement of draft ISO 9809-2, Transportation of Seamless Steel Gas
Cylinders--Design Construction and Testing--Part 2: Quenched and
Tempered Steel with Tensile Strength Greater Than or Equal to 1100 MPa.
(a) General requirements and definitions. Each Specification DOT
3FM seamless steel cylinder must meet the general requirements
contained in Secs. 178.69, 178.70 and the specific requirements
contained in this section.
(b) Authorized material and identification of materials. All
tubing, billet or cast stock must conform to Grade B or Grade E
material specified in Table 1 of Appendix A of this subpart.
(c) Manufacture. Closures formed by spinning are prohibited.
(d) Wall thickness. The minimum wall thickness must be such that
the wall stress at the prescribed minimum test pressure does not exceed
the lesser of 483 Mpa (70,000 psi) for Grade B material or 624 MPa
(90,500 psi) for Grade E material, or 67 percent of the minimum tensile
strength as determined from the mechanical properties tests prescribed
in paragraph 178.69(i)(7), but in no case may the minimum wall
thickness be less than 1.5 mm (.058 inch).
(e) Heat treatment. Each cylinder must be suitably quench and
temper heat treated and held at that temperature for a suitable period
of time. Each cylinder must then be air cooled under conditions
recommended for the steel. The minimum tempering temperature of the
metal must be at least 570 deg.C (1058 deg.F).
(f) Design qualification tests. The following design qualification
tests described in Sec. 178.69 apply:
(1) Cycle test. Cylinders representative of the design must
withstand, without distortion or failure, at least 10,000
pressurizations to the prescribed minimum test pressure.
(2) Burst test. Cylinders representative of the design, must have a
minimum burst of 1.6 times the marked test pressure.
(g) Production tests and verifications: The following examinations
and tests apply. Unless otherwise noted in this section, acceptable
results are prescribed in Sec. 178.69.
(1) Volumetric expansion test.
(2) Ultrasonic examination. The examination must be performed in
accordance with ASTM E 213 for the measurement of sidewall defects. Any
cylinder having a discontinuity greater than 24 mm (1 inch) in length
and a depth greater than 5 percent of the design minimum wall thickness
must be rejected.
(3) Hardness test. A hardness test must be performed on the
cylindrical section of each cylinder after heat treatment. The tensile
strength equivalent of the hardness number obtained from the test may
not be more than 1,140 MPa (166,000 psi). The hardness number may not
exceed 37 HRC or 344 HBS. If the hardness number is exceeded, then the
lot must be rejected.
(4) Mechanical tests. (i) Specimen size must be gauge length 50 mm
(2 inches) and a maximum width of 38 mm (1.5 inches). For cylinders
over 454 kg (1,000 pounds) water capacity, specimens may be the
Standard Round Tension Specimen as specified in ASTM A-370 (0.357
inches minimum diameter).
(ii) Elongation must be at least 16 percent for the 50 mm (2
inches) gauge length specimen. Tensile strength may not exceed 1,069
MPa (155,000 psi). For round specimens, the minimum elongation must be
at least 15 percent.
(5) Impact tests. (i) Three specimens must be impact tested per
lot. Each specimen must be taken from the sidewall of the cylinder or
test ring. The axis of the specimen must be perpendicular to the
longitudinal axis of the cylinder, with the axis of the notch in the
``T-L'' orientation as illustrated in figure 3 of ASTM E 399. Each
specimen must be Charpy V-Notch type, size 10
[[Page 58501]]
mm (.40 inch) x 5 mm (.20 inch) or 4 mm (.16 inch).
(ii) For cylinders over 454 kg (1,000 pounds) water capacity, the
axis of the specimen must be parallel to the longitudinal axis of the
cylinder, with the axis of the notch in the ``L-C'' orientation as
illustrated in figure 3 in ASTM E 399. Each specimen must be Charpy V-
Notch type, size 10 mm (.40 inch) x 10 mm (.40 inch) if cylinder
thickness permits. When only a reduced size specimen can be obtained,
it must be the largest standard size obtainable but not smaller than 10
mm (.40 inch) x 5 mm (.20 inch).
(iii) For cylinders constructed of Grade E material, the Charpy V-
Notch impact properties for the three specimens must be tested at minus
50 deg.C (minus 60 deg.F), or colder; and the values obtained may be
not less than the values shown in the following table. For cylinders
constructed of Grade B material, the Charpy V-Notch impact properties
for the three specimens must be tested at minus 50 deg.C (minus
60 deg.F ), or colder; and the values obtained must not be less than
the values shown in the following table:
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average value for acceptance Minimum value for acceptance
for 3 specimens for one specimen only of the 3
Size of specimen (mm) -------------------------------- specimens
-------------------------------
(ft-lb) (j/cm2) (ft-lb) (j/cm2)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Grade B
10.0 x 10.0................................ 25 42 20 34
10.0 x 7.5................................. 21 48 17 39
10.0 x 5.0................................. 17 58 14 47
Grade E
10.0 x 5.0................................. 15 50 12 40
10.0 x 4.0................................. 12 40 9.5 32
--------------------------------------------------------------------------------------------------------------------------------------------------------
59. Section 178.81 would be added to Subpart C to read as follows:
Sec. 178.81 Specification for DOT 4M; Welded metric-marked cylinders.
(a) General. DOT specification 4M cylinders must meet the
requirements contained in this section and Sec. 178.69.
(1) The design test pressure for DOT specification 4M cylinders
must be less than or equal to 140 bar (2030 psi).
(2) [Reserved]
(b) Lot size. For cylinders manufactured under the provisions of
this section, in no case may a lot size exceed 500.
(c) Authorized materials and identification of materials. For an
aluminum cylinder only Aluminum Association alloy 5154 is authorized.
For a steel cylinder, stock must conform to a material listed in Table
1 as follows:
[[Page 58502]]
[GRAPHIC] [TIFF OMITTED] TP30OC98.001
[[Page 58503]]
(d) Manufacture. (1) A DOT-4M specification cylinder must be
manufactured only by a process specifically authorized by and conform
to the applicable requirements of this section.
(2) The manufacturing process must produce cylinders that are free
of defects which are likely to weaken the finished cylinder. Heads must
be seamless, hemispherical or ellipsoidal in shape with the major
diameter not more than two times the minor diameter, or a dished shape
falling within these limits. For heads concave to pressure, the minimum
head thickness may not be less than 90 percent of the required
thickness of the sidewall. For heads convex to pressure, the minimum
thickness must be not less than two times the required thickness of the
sidewall. The bottom thicknesses must be measured within an area
bounded by a line representing the points of contact between the
cylinder and floor when the cylinder is in a vertical position. For
cylinders with a wall thickness less than 2.5 mm (0.100 inch), the
ratio of tangential length to outside diameter may not exceed 4.0.
(3) Welding processes and machine operators shall meet
qualification standards and comply with operating procedures specified
in CGA Pamphlet C-3.
(i) Circumferential seams must be butt welded with one member
offset (joggle butt) or lapped with minimum overlap of at least four
times wall thickness. Other butt joints must be authorized in writing
by the Associate Administrator. Fillet weld beads must be flat or
convex and the leg of any fillet weld subjected to shear stress must be
at least 1.3 times the shell wall thickness. For spheres, the maximum
joint efficiency for design calculations is 0.85. Heat affected zones
are considered to extend a distance of six times the wall thickness
from the center line of the weld.
(ii) Longitudinal seams must have complete penetration, and must be
free from undercuts, overlaps or abrupt ridges or valleys. Misalignment
of mating butt edges must not exceed 0.166 of the wall thickness or 0.8
mm (0.031-inch), whichever is less. For cylinders with nominal wall
thickness up to and including 3.2 mm (0.125 inch), joints must be
tightly butted. When wall thickness is greater than 3.2 mm (0.125
inch), the joint must be gapped with maximum distance equal to one-half
the wall thickness or 0.8 mm (0.031 inch) whichever is less.
(iii) The joint efficiency is 1.0, .90 or .75, as appropriate, for
welded joint described in paragraph (i)(6) of this section.
(iv) The tensile strength of welded joints must be equal to or
greater than the minimum required tensile strength of the shell
material of the finished cylinder.
(v) Attachments may not be welded to the sidewall of the cylinder.
Welding of attachments must be completed prior to all pressure tests
and prior to heat treatment when required. Attachments must be made of
weldable material of an alloy which is compatible with the cylinder.
The carbon content for steel attachments may not exceed 0.25 percent.
(e) Wall thickness. The minimum wall thickness of a DOT 4M cylinder
must be the greater of the thickness as determined by the following
criteria:
(1) The minimum wall thickness for a carbon steel, HSLA steel or
stainless steel cylinder with an outside diameter greater than 127 mm
(5 inches) must be 2.0 mm (0.078 inch) and for an aluminum cylinder
with an outside diameter greater than 127 mm (5 inches) must be 4 mm
(0.156 inch).
(2) The minimum wall thickness for a carbon steel, HSLA steel or
stainless steel cylinder with an outside diameter less than or equal to
127 mm (5 inches) must be 1.5 mm (.058 inch) and for an aluminum
cylinder 2.5 mm (0.097 inch).
(3) Each cylinder must have a wall thickness such that the wall
stress calculated at test pressure using the formula listed in
paragraph (e)(4)(i) and (ii) of this section may not exceed the
following allowable stresses at test pressure:
(i) For DOT 4M cylinders made from HSLA steel, 260 Mpa (37,000
psi).
(ii) For DOT 4M cylinders made from carbon steel, 165 Mpa (24,000
psi).
(iii) For DOT 4M cylinders made from aluminum alloy 5154, 138 Mpa
(20,000 psi).
(iv) For DOT 4M cylinders made from 4130X steel, 255 Mpa (70,000
psi).
(v) For DOT 4M cylinders made from stainless steel cylinders, 410
Mpa (60,000 psi).
(4) For minimum wall thickness calculations, one of the following
formula must be used:
(i) For cylinders that are cylindrical in shape:
S(MPa) = (P(1.3D\2\ + .4d\2\))/E(10(D\2\-d\2\))
Where:
S = Wall stress in MPa.
P = Minimum test pressure in bar, as prescribed for the hydrostatic
test.
D = Outside diameter in mm.
d = Inside diameter in mm.
E = Joint efficiency of the longitudinal seam.
(ii) For cylinders that are spherical in shape:
S(MPa) = PD / 40tE
Where:
S = wall stress in MPa.
P = Minimum prescribed test pressure in bar.
D = Outside diameter in mm.
t = Minimum wall thickness in mm.
E = weld efficiency factor.
(f) Openings. Openings must conform to the following:
(1) Openings are permitted in heads only. The opening must be
circular or elliptical.
(2) Openings must be provided with adequate fittings, bosses or
pads, integral with or securely attached to the cylinder by welding.
Each fitting, boss or pad must be compatible with the cylinder
material. Method of attachment must be the same as the method of
construction.
(3) When more than one opening exists in the head or bottom of the
cylinder, these openings must be separated by ligaments of at least
three times the average of their hole diameters.
(g) Heat treatment. When a completed cylinder is required to be
heat treated, each cylinder in a lot must be uniformly and properly
heat treated under similar conditions of time, temperature, cooling
rate and atmosphere prior to all tests. The furnace temperature for
heat treatment must be controlled on a continuous basis by use of
automated instrumentation to control performance.
(1) Heat treatment must follow all forming and welding operations.
(2) Each completed cylinder must be heat treated, as follows:
(i) Quench and temper heat treatment is authorized only for a DOT
4M cylinder made from 4130X steel.
(A) Tempering must be accomplished by reheating the quenched
cylinder to a temperature below the transformation range, and holding
at that temperature for at least one hour per 25 mm (1 inch) of
thickness, based on the shell thickness of the cylinder. Each cylinder
must then be air cooled under uniform conditions.
(B) The tempering temperature of the 4130X steel must be at least
538 deg.C (1000 deg.F).
(ii) Stress relieving heat treatment for HSLA steel and carbon
steel cylinders must be at a temperature of at least 593 deg.C (1100
deg.F).
(iii) Normalizing heat treatment for HSLA steel and carbon steel
cylinders must be at a temperature of at least 870 deg.C (1600
deg.F).
(iv) Heat treatment is not required for a stainless steel.
(v) For an aluminum alloy 5154 cylinder, heat treatment is not
required.
[[Page 58504]]
(h) Design qualification tests. The following design qualification
test described in Sec. 178.69 apply. Burst test: five representative
cylinders of each design, or any significant change to a previously
tested design, must be burst tested. Each test cylinder must achieve
the minimum burst pressure as specified in Table 2 of paragraph (i) of
this section without leakage or rupture.
(i) Production tests. The following examinations and tests apply.
Unless otherwise noted in this section, procedures and acceptable
results are prescribed in Sec. 178.69.
(1) Pressure test. Pressure testing must conform to the frequency,
schedules and pressures as specified in Table 2 of this paragraph (i).
(2) Leak test. Each fully assembled cylinder must be subjected to a
gas leakage test, using a dry inert gas, at one half the design test
pressure while the cylinder is immersed in water, by coating it with a
leak detecting solution, or by an alternate test method approved by the
Associate Administrator. Table 2 follows:
Table 2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Volumetric \1\ expansion test
---------------------------------------------------
DOT spec. Lot size Maximum Proof test pressure \3\ Minimum burst
Test pressure(TP) permitted PVE/ pressure \4\
TVE \2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
4M \5\............................. 500 As marked........................ 10% @ TP....................... 2 x TP
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ At least one cylinder per lot must be subjected to volumetric expansion test. If each cylinder is subjected to the volumetric expansion test the
proof test is not required.
\2\ PVE = permanent volumetric expansion; TVE = total volumetric expansion.
\3\ Each cylinder must be proof tested at the TP.
\4\ One cylinder per lot must be pressurized to destruction; minimum burst is expressed in multiples of TP.
\5\ See Secs. 173.302b and 173.304b of this subchapter for fill (service) pressure of DOT 4M cylinders.
(3) Mechanical tests. Mechanical tests must be taken from a minimum
of two sample cylinders per lot selected at random after pressure test
and heat treatment, if required. Test specimens must be taken as
depicted in figures 1 through 5 of Appendix C of this subpart for the
specific design utilized for construction.
(i) For cylinders and spherical shapes which are not of sufficient
size to secure test specimens, an alternate testing protocol must be
approved in writing by the Associate Administrator.
(ii) A test cylinder need represent only one of the heats of
material of construction in the lot, provided that other heats in the
lot have been tested and passed when heat treated under similar
conditions.
(iii) If, due to welded attachments on the heads, there is
insufficient surface from which to take specimens, specimens may be
taken from a cylinder prepared as a test cylinder which does not have
the attachments but is the same as the other cylinders in the lot and
is heat treated with the lot it represents.
(iv) Minimum elongations are specified in Table 3 or Table 4 of
this paragraph (i), as appropriate.
(v) Acceptable results. The yield strength may not exceed 73
percent of tensile strength for carbon steel and 80 percent of tensile
strength for aluminum alloy 5154.
(4) Flattening test. A flattening test must be performed on a test
cylinder selected from each lot. Cylinders must be flattened, without
cracking, between knife edges as specified in Sec. 178.69(i)(1) to six
times the wall thickness for steel cylinders and ten times the wall
thickness for aluminum cylinders. The minimum distance is to be
measured between the knife edges or plates while the specimens are
under compression. For spherical shapes, flattening is to be performed
on a press, between parallel steel plates with the welded seam at right
angles to the plates. Alternatively, a test ring cut from the sphere
which includes the weldment and at least one inch of material on each
side may be crushed between parallel steel plates with welded seam at
right angles to the plates. Any projecting appurtenances may be removed
prior to flattening. Removal must not produce a temperature exceeding
204 deg.C (400 deg.F).
(5) Burst test. For production testing one cylinder selected at
random from each lot must be burst tested. Each test cylinder must
achieve the minimum burst pressure as specified in Table 2 of this
paragraph (i) without leakage or rupture.
(6) Joint efficiency. (i) The joint efficiency is 1.0 when all weld
seams, both longitudinal and circumferential, are completely
radiographically examined and defects removed. Weld repair areas must
be reinspected to confirm that defects have been removed and the
repaired area is of acceptable weld quality.
(ii) The joint efficiency is 0.90 when one cylinder from the first
10 production cylinders and one cylinder from each 100 consecutively
welded cylinders thereafter are completely radiographically examined
and show no defects. When defects are found in the sample cylinder all
cylinders welded since the last acceptable sampling must be inspected
completely and defects removed and repaired. When welding operations
are suspended for more than four hours one cylinder must be inspected
completely from the first 10 production cylinders after resumption of
welding.
(iii) The joint efficiency is 0.75 when there is no radiographic
weld examination.
(iv) A cylinder which is less than 21.4 kg (48 lbs) water capacity
and test pressure less than 34.5 bar (500 psig) manufactured to a two
piece design has a joint efficiency of 1.0 and requires no radiographic
examination.
(v) Radiographic examination is required for DOT 4M cylinders
constructed from 4130X steel and all DOT 4M cylinders with design test
pressure equal to or greater than 70 bar (1015 psi). Radiographic
examination must be performed on all welded joints which are subjected
to internal pressure.
(vi) As an alternative to radiographic examination, an ultrasonic
examination may be used in accordance with Appendix B of this subpart.
(7) Mechanical test of welds. Tests must be performed on specimens
taken, as illustrated in Figure 1 through 5 of Appendix C of this
subpart, from a cylinder chosen at random from each lot. Acceptable
results:
(i) Tensile test results must meet acceptance criteria specified in
CGA Pamphlet C-3 with specimen failure at a stress of not less than two
times the wall stress at test pressure, calculated using the actual
wall thickness.
(ii) Guided bend test results must meet acceptance criteria
specified in CGA Pamphlet C-3.
[[Page 58505]]
(iii) Alternate guided bend test results must meet acceptance
criteria specified in CGA Pamphlet C-3 and Sec. 178.69(i)(8)(iii).
Tables 3 and 4 follow:
Table 3.--Elongation
----------------------------------------------------------------------------------------------------------------
Minimum elongation (in percent)
-----------------------------------------------
Gauge length Gauge length
x width ((50 x width \1\
Material mm x 38 mm)(2 38 of 24t x
inch x 1.5 inch)) 1.5 6t
inch))
----------------------------------------------------------------------------------------------------------------
Aluminum, alloy 5154............................................ 12 12 12
Steel (tensile strength <3447 MPA (50,000 psi))................. 40 20 20
----------------------------------------------------------------------------------------------------------------
Note 1: A gauge length of at least 24 times shell thickness and a width of not greater than six times shell
thickness is authorized when cylinder wall is not greater than 4.7 mm (0.188 inch) thick.
Table 4.--Alternate Minimum Elongation
----------------------------------------------------------------------------------------------------------------
Alternate minimum elongation (in percent)
-----------------------------------------------------------------------------------------------------------------
Shell tensile strength Having tensile strength >3447 MPA (50,000 psi)
----------------------------------------------------------------------------------------------------------------
Gauge length
x width ((50 Gauge length
mm x 38 mm) (2 ((200 mm x Gauge length
MPA PSI inch x 38 of 24t x
thn-eq>1.5 mm)(8 inch x width\1\ of 6t
inch)) 1.5
inch))
----------------------------------------------------------------------------------------------------------------
3964....................... 57500........ 38 19 19
4482....................... 65000........ 36 18 18
5000....................... 72500........ 34 17 17
5520....................... 80000........ 32 16 16
----------------------------------------------------------------------------------------------------------------
Note 1: A gauge length of at least 24 times shell thickness and a width of not greater than six times shell
thickness is authorized when cylinder wall is not greater than 4.7 mm (0.188 inch) thick.
(j) [Reserved]
(k) Cylinder Rejection. Each test cylinder or each lot represented
by a test cylinder that does not meet the acceptable test results must
be rejected. When a lot of cylinders is rejected, due to failure of the
mechanical, flattening, or weld test, the lot may be reheat treated and
retested as if it were a new lot. Reheat treatment is limited to two
times.
(l) Leakage test. A spun cylinder rejected under paragraph (i)(2)
of this section must be scrapped, condemned or rendered incapable of
holding pressure.
(m) Repairs. A repair of weld seams is authorized using the same
process as that used for the original welding. A rewelded cylinder must
be reheat treated and pass all prescribed tests.
60. Appendices A, B and C would be added to Subpart C of Part 178
to read as follows:
Appendix A to Subpart C of Part 178--Specifications for Steel,
Nickel and Aluminum
Table 1.--Steel and Nickel--Heat Analysis--Chemical Composition in Weight Percent
[For grades A-E, incidental elements to be within the limits specified in the AISI Manual 1for Semifinished Steel Products.]
--------------------------------------------------------------------------------------------------------------------------------------------------------
B min/
Grade Type of material C min/max Mn min/max P max S max Si min/max Cr min/max Mo min/max Ni min/max max Fe
--------------------------------------------------------------------------------------------------------------------------------------------------------
A........... Carbon \3\ 0.10/0.50 --/1.75 0.035 0.025 --/0.30 ........... ........... ........... ....... Bal.
Manganese.
B........... Chrome Moly Type... 0.25/0.50 0.40/1.05 0.035 0.025 0.15/0.35 0.80/1.15 0.15/0.25 ........... ....... Bal.
C........... Stainless \2\...... --/0.080 --/2.00 0.035 0.030 --/1.00 16.0/20.0 2.00/3.00 8.0/15.0 ....... Bal.
D........... Nickel............. ........... ........... ....... ....... ........... ........... ........... 99.0/-- ....... Bal.
E........... Chrome \4\ Moly 0.32/0.38 0.60/1.05 0.015 0.010 0.15/0.35 0.80/1.15 0.15/0.25 ........... ....... Bal.
Type.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The AISI manual referenced in the heading means ``American Iron and Steel Institute'' Steel Products Manual--Alloy, Carbon, and High Strength Low
alloy Steels; Semifinished: dated March 1986.
\2\ The minimum for molybdenum (2.00) shown, applies only to Stainless Steel type 316.
\3\ Forging or drawing quality steel required; rimmed steel not authorized.
\4\ Forging or drawing quality steel required; produced to predominantly fine grain practice.
Table 2.--Aluminum--Heat or Cast Analysis for Aluminum; Similar to ``Aluminum Association'' \1\ Alloy 6061 Chemical Analysis in Weight Percent \2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Other
------------------
Si min/max Fe max Cu min/max Mn max Mg min/max Cr min/max Zn max Ti max Pb max Bi max Each Total Al
max max
--------------------------------------------------------------------------------------------------------------------------------------------------------
0.40/0.80.. 0.70 0.15/0.40 0.15 0.80/1.20 0.04/0.35 0.25 0.15 0.005 0.005 0.05 0.15 Bal.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The ``Aluminum Association'' refers to ``Aluminum Standards and Data 1993'', published by the Aluminum Association Inc.
[[Page 58506]]
\2\ Except for ``Pb'' and ``Bi'', the chemical composition corresponds with that of Table 1 of ASTM B221M for Aluminum Association alloy 6061.
Mechanical Properties
[Aluminum in conformance with the specification in Table 2 above,
thermally treated to ``T6'' temper]
------------------------------------------------------------------------
Elongation, percent
Tensile strength Yield strength minimum minimum, for 2 inch or
minimum (Mpa) \1\ (Mpa) \1\ 4D \2\ size specimen
------------------------------------------------------------------------
262.................... 241 14 \3\
------------------------------------------------------------------------
\1\ MPA x 145 = psi.
\2\ ``D'' represents specimen diameter. When the cylinder is over 3/16
inch thick, a retest without reheat treatment, using the 4D specimens
is authorized, if the test using the 2 inch size specimen fails to
meet elongation requirements.
\3\ ``10 percent'' minimum elongation is authorized, when using a 24t x
6t test specimen if the cylinder sidewall is not over 3/16 inch thick.
Appendix B To Subpart C of Part 178--Ultrasonic Examination of
Cylinders
Ultrasonic examination (UT) includes straight beam pulse echo
testing that measures 100 percent of the cylinder's sidewall
thickness and angle beam (shear wave) pulse echo that identifies and
measures cracks, pits, laminations, laps, and other defects.
a. UT equipment. The UT equipment shall consist of a pulse-echo
test instrument that is capable at a minimum, of generating,
receiving, and presenting high energy pulses in an A-scan
presentation on a display. It must have a minimum frequency of 1.0
MHZ and a minimum frequency range of 1.0 to 5.0 MHZ.
1. The UT equipment must continually monitor the acoustic
coupling to assure 100% cylinder sidewall coverage during the
testing and automatically terminate the testing if the coupling is
lost. The equipment also must be capable of providing a linear
presentation of crack depth. The equipment calibration must be
verified for each type of cylinder to be examined using the
calibration standard in paragraph b of this Appendix prior to
testing. At a minimum, the equipment calibration must be verified at
the beginning of each work shift, not to exceed 10 continuous hours.
2. The UT equipment must have multiple focused array transducers
to perform both straight beam and angle beam testing of the cylinder
sidewall and sidewall to base transition. A straight-beam search
unit consists of a piezoelectric crystal mounted to a fixture that
is perpendicular to the longitudinal axis of the cylinder. A shear
wave search unit consists of piezoelectric crystals mounted to a
fixture that are angled at 45 deg. or 60 deg. to the longitudinal
axis of the cylinder sidewall. The frequency and angle of each
search unit must be determined during calibration based on material,
diameter, and wall thickness of the cylinder. A proper search unit
must be selected to obtain a good resolution and a minimum accuracy
of +/-5% of the defect depth. A search unit frequency of 2.25 MHZ to
10.0 MHZ must be used. The equipment used must be calibrated to
detect a discontinuity 25.4 mm (1 inch) in length and a depth of 5
percent of the prescribed minimum wall thickness.
b. Calibration standard. A cylinder used as a calibration
standard must be of the same diameter (+/-10%), surface finish,
metallurgical type, and specification as the cylinders to be tested,
for example, a DOT 3FM calibrated cylinder must be used for 3FM
cylinders. The calibration cylinder must be machined with features
that simulate defects such as pits, fatigue cracks, and reduced wall
thickness. The size of the defect feature shall be approximately the
same as the applicable pass-fail criteria identified in Table II of
Sec. 180.207 of this subchapter for requalification of metric-marked
cylinders, as identified in Table II of Sec. 180.209 of this
subchapter for requalification of nonmetric-marked cylinders or as
identified in the applicable cylinder specification. The minimum
wall thickness and defect sizes in the calibration cylinder must be
confirmed by mechanical measurements and certified by a non-
destructive testing (NDT) Level III in UT. The size of the defect
features in the calibration cylinder shall be measured every five
years to confirm that the defect sizes have not been changed. A
certification statement signed by a person certified to NDT Level
III in UT must be maintained for each calibration standard and made
available for review, upon request, by an authorized RSPA
representative.
c. Couplant. The same couplant must be used for both calibration
and actual testing.
d. UT procedure and reporting requirements. The UT procedure and
reporting requirements used must be in accordance with ASTM E 797
for wall thickness measurement and ASTM E 213 for sidewall defect
measurement. The UT program must be approved in writing by the
Associate Administrator.
1. The surface of the cylinder to be inspected shall be free of
extraneous loose material such as scale, loose paint, and dirt.
2. The rotational speed of the cylinder under examination may
not exceed the rotational speed used during calibration.
3. The UT results must be evaluated in accordance with pass-fail
criteria identified in Table II of Sec. 180.207 of this subchapter
for requalification of metric-marked cylinders, as identified in
Table II of Sec. 180.209 of this subchapter for requalification of
nonmetric-marked cylinders or as identified in the applicable
cylinder specification.
e. Personnel Qualifications and Responsibilities: Each facility
where testing is to be performed must be under the managerial
direction of a Senior Review Technologist (SRT).
1. The SRT must define the overall test program, provide
supervisory training and technical guidance to operators, review and
certify test results and maintain proof of qualifications for each
``qualified tester''. The SRT must have a Level III, UT
Certification, in accordance with the ASNT Recommended Practice SNT-
TC-1A and a thorough understanding of this subchapter pertaining to
the qualification and use of DOT cylinders.
2. The person performing cylinder testing, the ``qualified
tester'', must be at a minimum a qualified Level II, UT in
accordance with ASNT-TC-1A. The ``qualified tester'' may perform
system startup, calibrate the system, and review and validate the
test results.
3. A person with Level I certification may perform a system
startup, check calibration, and perform UT only under the direct
guidance, supervision, and observation of a Level II or Level III
Operator.
4. Each ``qualified tester'' must have written procedures for
conducting UT, for operation of equipment, a copy of this
subchapter, proof of qualifications, and records of all tests
performed at the facility where testing is performed.
[[Page 58507]]
[GRAPHIC] [TIFF OMITTED] TP30OC98.002
[[Page 58508]]
[GRAPHIC] [TIFF OMITTED] TP30OC98.003
[[Page 58509]]
[GRAPHIC] [TIFF OMITTED] TP30OC98.004
[[Page 58510]]
[GRAPHIC] [TIFF OMITTED] TP30OC98.005
[[Page 58511]]
[GRAPHIC] [TIFF OMITTED] TP30OC98.006
BILLING CODE 4910-60-C
[[Page 58512]]
PART 180--CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS
61. The authority citation for Part 180 would continue to read as
follows:
Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.
62. Subpart C would be added to Part 180 to read as follows:
Subpart C--Qualification, Maintenance and Use of Cylinders
Sec.
180.201 Applicability.
180.203 Definitions.
180.205 General requirements for requalification of cylinders.
180.207 Requirements for requalification of metric-marked
specification cylinders.
180.209 Requirements for requalification of nonmetric-marked
specification cylinders.
180.211 Repair, rebuilding and reheat treatment of nonmetric-marked
DOT-4 series specification cylinders.
180.213 Requalification markings.
180.215 Reporting and record retention requirements.
Subpart C--Qualification, Maintenance and Use of Cylinders
Sec. 180.201 Applicability.
This subpart prescribes requirements, in addition to those
contained in Parts 107, 171, 172, 173 and 178 of this chapter,
applicable to any person responsible for the continuing qualification,
maintenance, or periodic requalification of DOT specification and
exemption cylinders.
Sec. 180.203 Definitions.
In addition to the definitions contained in Secs. 171.8 and 178.69
of this subchapter, the following definitions apply to this subpart:
Associate Administrator means Associate Administrator for Hazardous
Materials Safety.
Commercially free of corrosive components means a hazardous
material having a dew point at or below minus 46.7 deg.C (minus 52
deg.F) at 101kPa (1 atmosphere) and free of material that will
adversely react with the cylinder (e.g. chemical stress corrosion).
Condemn means a determination that a cylinder is unserviceable for
the continued transportation of hazardous materials in commerce and
that the cylinder may not be restored by repair, rebuilding,
requalification or any other procedure.
Defect means an imperfection that requires removal of a cylinder
from service.
Elastic expansion means the temporary increase in a cylinder's
volume, due to application of pressure, which is lost when pressure is
released.
Filled means an introduction or presence of a hazardous material in
a cylinder.
Non-corrosive service means a hazardous material that is not
corrosive to the materials of construction of a cylinder (including
valve, pressure relief device, etc.) when moisture is introduced into
the cylinder.
Over-heated means a condition in which any part of a cylinder has
been subjected to a temperature in excess of 176 deg.C (350 deg.F).
Over-pressurized means a condition in which a cylinder has been
subjected to an internal pressure in excess of 30% of its test
pressure.
Permanent expansion means the permanent increase in a cylinder's
volume after the test pressure is released (permanent expansion = total
expansion minus elastic expansion).
Proof pressure test means a pressure test by interior
pressurization without the determination of the cylinder's expansion.
Rebuild means the replacement of a pressure part (e.g. a wall, head
or pressure fitting) by welding.
Rejected cylinder means a cylinder that can not be used for the
transportation of a hazardous material in commerce without repair,
rebuild or requalification.
Repair means a procedure for correction of a rejected cylinder and
may involve welding.
Requalification means the completion of a visual inspection and or
the test(s) that are required to be performed on a cylinder to
determine its suitability for continued service.
Requalification identification number or RIN means a code assigned
by DOT to uniquely identify a cylinder requalification, repair or
rebuilding facility.
Test pressure means the pressure used for the requalification of a
cylinder.
Total expansion means the total increase in a cylinder's volume due
to application of the test pressure.
Visual inspection means an internal or external visual examination,
or both, performed as part of the cylinder requalification process.
Volumetric expansion test means a pressure test by interior
pressurization to measure a cylinder's expansion by using the water
jacket or direct expansion methods:
(1) Water jacket method means a volumetric expansion test to
determine a cylinder's total and permanent expansion by measuring the
difference between the volume of water the cylinder externally
displaces at test pressure and the volume of water the cylinder
externally displaces at ambient pressure.
(2) Direct expansion method means a volumetric expansion test to
calculate a cylinder's total and permanent expansion by measuring the
amount of water forced into a cylinder at test pressure, adjusted for
the compressibility of water, as a means of determining the expansion.
Sec. 180.205 General requirements for requalification of cylinders.
(a) General. Each cylinder used for the transportation of hazardous
materials must be an authorized packaging. To qualify as an authorized
packaging, each cylinder must conform to this subpart, the applicable
requirements specified in part 173 of this subchapter, and the
applicable requirements of subpart C of part 178 of this subchapter.
(b) Persons performing requalification functions. No person may
represent that a repair or requalification of a cylinder has been
performed unless that person holds a current approval issued under the
procedural requirements prescribed in subpart I of part 107 of this
chapter. No person may mark a cylinder with a RIN and a requalification
date or otherwise represent that a DOT specification or exemption
cylinder has been requalified unless all applicable requirements of
this subpart have been met. A person who requalifies cylinders shall
maintain, at each location at which it inspects, tests or marks
cylinders, the records prescribed in Sec. 180.215.
(c) Periodic requalification of cylinders. Each cylinder bearing a
DOT specification marking must be requalified and marked as specified
in the Requalification Table in this subpart. Each cylinder bearing a
DOT exemption number must be requalified and marked in conformance with
this section and the terms of the applicable exemption. No cylinder may
be charged or filled with a hazardous material and offered for
transportation in commerce unless that cylinder has been successfully
requalified and marked in accordance with this subpart. A cylinder may
be requalified at any time during the month and year that the
requalification is due. However, a cylinder that was charged or filled
before the requalification became due may remain in service until it
has been emptied.
(1) Each cylinder that successfully passes requalification
specified in this section must be marked in accordance with
Sec. 180.213.
(2) Each cylinder that fails requalification must be:
[[Page 58513]]
(i) Rejected and may be requalified in accordance with
Sec. 180.211; or
(ii) Condemned in accordance with paragraph (i) of this section.
(3) For nonmetric-marked DOT specification cylinders, the marked
service pressure may be changed upon application to the Associate
Administrator and receipt of written procedures.
(4) For a metric-marked cylinder, the start-to-discharge pressure
of a pressure relief device must not be less than the marked test
pressure of the cylinder. For a nonmetric-marked DOT-3 series cylinder,
the start-to-discharge pressure of a pressure relief device must be set
to not less than 100% of the minimum required test pressure at the
first requalification due on and after [EFFECTIVE DATE OF THE FINAL
RULE]. To ensure that the relief device does not open below its set
pressure, the allowable tolerances for all the pressure relief devices
must range from zero to plus 10% of its setting.
(d) Conditions requiring test and inspection of cylinders. Without
regard to any other periodic requalification requirements, a cylinder
must be tested and inspected in accordance with this section prior to
further use if--
(1) The cylinder shows evidence of dented, corroded, cracked or
abraded areas, leakage, thermal damage or any other condition that
might render it unsafe for use in transportation.
(2) The cylinder has been in an accident and has been damaged to an
extent that may adversely affect its lading retention capability.
(3) The cylinder has been over-heated or over-pressurized.
(4) The Associate Administrator determines that the cylinder may be
in an unsafe condition.
(e) Cylinders containing Class 8 materials. A cylinder that
previously contained a Class 8 material may not be used to transport a
Class 2 material in commerce unless the cylinder is--
(1) Visually inspected, internally and externally, in accordance
with paragraph (f) of this section and the inspection is recorded as
prescribed in Sec. 180.215;
(2) Requalified in accordance with this section, regardless of the
date of the previous requalification;
(3) Marked in accordance with Sec. 180.213;
(4) Decontaminated and the decontamination removes all significant
residue or impregnation of the Class 8 material.
(f) Visual inspection. Except as otherwise provided in this
subpart, each time a cylinder is pressure tested, it must be given an
internal and external visual inspection. When a pressure test is not
performed, the cylinder must be given an external visual inspection.
(1) The visual inspection must be performed in accordance with the
following CGA Pamphlets: C-6 for steel and nickel cylinders; C-6.1 for
seamless aluminum cylinders; C-6.2 for fiber reinforced exemption
cylinders; C-6.3 for low pressure aluminum cylinders; C-8 for DOT 3HT
cylinders, and C-13 for DOT 8 series cylinders.
(2) Each cylinder with a vinyl or plastic coating must have the
coating completely removed prior to performing the visual inspection.
(3) Each cylinder subject to visual inspection must be approved,
rejected or condemned according to the criteria in the applicable CGA
pamphlet.
(4) In addition to other requirements prescribed in this paragraph,
DOT 3AL cylinders must be inspected for evidence of sustained load
cracking in the neck and shoulder area in accordance with the cylinder
manufacturer's written recommendations which have been approved in
writing by the Associate Administrator.
(g) Pressure test. Unless otherwise excepted, the pressure test
must be conducted in accordance with the procedures in paragraphs 4, 5
and 6 and Appendices A and B of CGA Pamphlet C-1. Bands and other
removable attachments must be loosened or removed before testing so
that the cylinder is free to expand in all directions.
(h) Cylinder rejection. A cylinder must be rejected when, after a
visual inspection, it meets a condition for rejection under the visual
inspection requirements of paragraph (f) of this section.
(1) A cylinder that is rejected may not be marked as meeting the
requirements of this section.
(2) The requalifier shall notify the cylinder owner, in writing,
that the cylinder has been rejected and, unless requalified as provided
in Sec. 180.211, may not be filled with a hazardous material for
transportation in commerce where use of a specification packaging is
required.
(3) A rejected nonmetric-marked cylinder with a service pressure of
less than 900 psig may be requalified and marked if the cylinder is
repaired or rebuilt and subsequently inspected and tested in
conformance with--
(i) The visual inspection requirements of paragraph (f) of this
section;
(ii) Part 178 of this subchapter and this part;
(iii) Any exemption covering the manufacture, requalification, and
or use of that cylinder; and
(iv) Any approval required under Sec. 180.211.
(i) Cylinder condemnation. (1) A cylinder must be condemned when--
(i) The cylinder meets a condition for condemnation under the
visual inspection requirements of paragraph (f) of this section;
(ii) The cylinder leaks through its wall;
(iii) Evidence of cracking exists to the extent that the cylinder
is likely to be weakened appreciably;
(iv) A DOT specification cylinder (including 4M), other than a DOT
4E aluminum cylinder or an exemption cylinder, permanent expansion
exceeds 10 percent of total expansion;
(v) A DOT 3HT cylinder--
(A) Yields an elastic expansion exceeding the marked rejection
elastic expansion (REE) value during the pressure test. A cylinder made
before January 17, 1978, and not marked with an REE in cubic
centimeters near the marked original elastic expansion must be so
marked before the next test date. The REE for the cylinder is 1.05
times its original elastic expansion;
(B) Shows evidence of denting or bulging; or
(C) Bears a manufacture or an original test date older than twenty-
four years or after 4,380 pressurizations, whichever occurs first. If a
cylinder is refilled, on average, more than once every other day, an
accurate record of the number of rechargings must be maintained by the
cylinder owner or the owner's agent;
(vi) A DOT 4E or 4M aluminum cylinder's permanent expansion exceeds
12 percent of total expansion;
(vii) A DOT exemption cylinder's permanent expansion exceeds the
limit in the applicable exemption, or the cylinder meets another
criterion for condemnation in the applicable exemption;
(viii) An aluminum or an aluminum-lined composite exemption
cylinder is exposed to a temperature exceeding 177 deg.C (350 deg.F);
or
(ix) A DOT specification cylinder requalified by ultrasonic
examination that exceeds the minimum rejection criteria set forth in
Table II of Sec. 180.207 or Sec. 180.209, as applicable.
(2) When a cylinder is required to be condemned, the requalifier
shall stamp a series of X's over the DOT specification number and the
marked pressure or stamp ``CONDEMNED'' on the shoulder, top head, or
neck using a steel stamp. Alternatively, at the direction of the owner,
the requalifier may render the cylinder incapable of
[[Page 58514]]
holding pressure. In addition, the requalifier shall notify the
cylinder owner, in writing, that the cylinder is condemned and may not
be filled with hazardous material for transportation in commerce where
use of a specification packaging is required.
(3) No person may remove or obliterate the ``CONDEMNED'' marking.
Sec. 180.207 Requirements for requalification of metric-marked
specification cylinders.
(a) Each metric-marked cylinder that becomes due for periodic
requalification as specified in Table I of this section must be
inspected, tested, and marked in conformance with the requirements of
this subpart. The ultrasonic examination must meet the requirements in
Table II of this section. The recordkeeping requirements for an
ultrasonic examination must be in accordance with Sec. 180.215. The
ultrasonic examination procedures and equipment must be approved by the
Associate Administrator and meet the requirements set forth in Appendix
B of Subpart C of Part 178 of this subchapter. Other nondestructive
examinations (NDE) may be used only if approved in writing by the
Associate Administrator.
(b) Except as otherwise provided, DOT 3FM, 3ALM and 3M cylinders
must have 100% of the cylindrical section tested by straight-beam and
angle-beam. For a DOT 4M cylinder with a marked test pressure greater
than 70 bar or tensile strength greater than or equal to 830 Kpa
(120,000 psi), 100% of the cylindrical section must be tested by
straight-beam and angle-beam. For a DOT 4M cylinder with a marked test
pressure of 70 bar or less and tensile strength less than 830 Kpa
(120,000 psi), 100% of the cylindrical section must be tested by
straight beam if an ultrasonic examination is performed.
Tables to Sec. 180.207
Table I to Sec. 180.207.--Requalification of Metric-Marked Cylinders
--------------------------------------------------------------------------------------------------------------------------------------------------------
Type of service
Interval period (years) Test of inspection Specifications -------------------------
First subseq.
--------------------------------------------------------------------------------------------------------------------------------------------------------
External visual inspection.............. DOT-3M, 3FM, 3ALM, 4M.......... External visual inspections in accordance with the ........... ...........
applicable CGA pamphlet must be performed in
conjunction with the ultrasonic examination.
INTERNAL and EXTERNAL VISUAL INSPECTION. DOT-4M......................... Except as otherwise provided, the internal and ........... ...........
external visual inspections must be performed in
conjunction with the pressure test and in
accordance with the applicable CGA pamphlet.
Ultrasonic EXAMINATION.................. DOT 3M, 3FM, 3ALM, 4M.......... All, except cylinders used exclusively for the 5 5
material listed below:.
DOT 3M, 3FM, 3ALM.............. (1) Nonliquefied or liquefied, noncorrosive,
nontoxic (the LC50 of the lading is not less than
5000 ppm) gases that are commercially free from
corrosive components, and in cylinders protected
externally by a suitable corrosion-resistant
coating. A coating on a stainless steel or
aluminum cylinder is optional.
(2) Class 3 (flammable) liquids without
pressurization that are nontoxic (except 6.1 PG
III) and are commercially free from corroding
components.
(3) Class 8 (corrosive) liquids without 10 10
pressurization that are nontoxic (except 6.1 PG
III) and do not meet the criteria of Sec.
173.137(c)(2) of this subchapter. See restriction
in Sec. 180.205(e).
DOT 3M......................... Anhydrous ammonia commercially free from corrosive 10 10
components, and in cylinders protected externally
by a suitable corrosion-resistant coating.
DOT 4M (DOT 4M cylinders with a (1) Nonliquefied or liquefied, noncorrosive,
test pressure of 70 bar or nontoxic (the LC50 of the lading is not less than
less may be tested by a 5000 ppm) gases that are commercially free from
volumetric expansion test). corrosive components, and in cylinders protected
externally by a suitable corrosion-resistant
coating. A coating on a stainless steel or
aluminum cylinder is optional.
(2) Class 3 liquids without pressurization that are 15 15
nontoxic (except 6.1 PG III) and are commercially
free from corrosive components.
(3) Class 8 (corrosive) liquids without
pressurization that are nontoxic (except 6.1 PG
III) and do not meet the criteria of Sec.
173.137(c)(2) of this subchapter. See restriction
in Sec. 180.205(e).
DOT 3M and 4M (DOT 4M cylinders Specification cylinders used exclusively as fire 12 12
with a test pressure of 70 bar extinguishers and meeting the limitations in
or less may be tested by a special provision 18 in Sec. 172.102(c)(1) of
volumetric expansion test). this subchapter.
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 58515]]
Table II to Sec. 180.207.--Criteria for Periodic Ultrasonic Examination of Metric Marked Cylinders
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rejected area
for reduced wall
Coverage area Rejectable crack Rejectable crack thickness (t)
of cylinder by Coverage area Rejectable crack length in size in the Rejectable pit reduced wall
DOT specification straight beam of cylinder by depth in sidewall sidewall circumferential size diameter t=any value less
(longitudinal angle beam (% of wall (multiple of welded joint (D) x depth than design min.
wave) (shear wave) thickness) wall thickness) (depth x wall t\1\
length) D=diameter of
the cylinder
--------------------------------------------------------------------------------------------------------------------------------------------------------
3FM.......................... 100% of 100% of 10% of Wall...... 4 times Wall.... NA.............. 3 mm x \1/3\ 161 mm\2\ or
sidewall. sidewall. Thickness........ Thickness....... of the Designed 0.002D\2\.
Wall Thickness.
3ALM......................... 100% of 100% of 15% of Wall...... 5 times Wall.... NA.............. 3 mm x \1/3\ 323 mm\2\ or
sidewall. sidewall. Thickness........ Thickness....... of the Designed 0.004D\2\.
Wall Thickness.
3M........................... 100% of 100% of 15% of Wall...... 5 times Wall.... NA.............. 3 mm x \1/3\ 323 mm\2\ or
sidewall. sidewall. Thickness........ Thickness....... of the Designed 0.004D\2\.
Wall Thickness.
4M with a marked test 100% of 100% of 10% of Wall...... 4 times Wall.... 10% of Wall 3 mm x \1/3\ 323 mm\2\ or
pressure >70 bar or tensile sidewall. sidewall. Thickness........ Thickness....... Thick (Depth) of the Designed 0.004D\2\.
strength 830 MPa. and 2 times of Wall Thickness.
Wall Thick,
(Length).
4M with a marked test 100% of NA............ NA............... NA.............. NA.............. NA.............. 323 mm\2\ or
pressure 70 bar sidewall. 0.004D\2\.
or tensile strength <830 MPa.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Term wall thickness in this table means the minimum design wall thickness provided in the manufacturers inspection report.
Sec. 180.209 Requirements for requalification of nonmetric-marked
specification cylinders.
(a) Periodic qualification of cylinders. (1) Each nonmetric-marked
cylinder that becomes due for periodic requalification, as specified in
the following table, must be requalified and marked in conformance with
the requirements of this subpart. The recordkeeping requirements must
be in accordance with Sec. 180.215. Table I follows:
Table I.--Requalification of Nonmetric-marked Cylinders \1\
------------------------------------------------------------------------
Specification under which Minimum test
cylinder was made \2\ pressure (p.s.i.) Test period (years)
---------------------------------------\3\------------------------------
DOT-3....................... 3,000 p.s.i......... 5.
DOT-3A, 3AA................. 5/3 times service 5, 10, or 12 (see
pressure, except Sec. 180.209 (b),
noncorrosive (f), (h) and (j)).
service (see Sec.
180.209(g)).
DOT-3AL..................... 5/3 times service 5 or 12 (see
pressure. 180.209(j)).
DOT-3AX, 3AAX............... 5/3 times service 5.
pressure.
3B, 3BN..................... 2 times service 5 or 10 (see Sec.
pressure (see Sec. 180.209(f)).
180.209(g)).
3E.......................... Test not required.
3HT......................... 5/3 times service 3 (see Sec.
pressure. 180.209(i) and
180.213(c)).
3T.......................... 5/3 times service 5.
pressure.
4AA480...................... 2 times service 5 or 10 (see Sec.
pressure (see Sec. 180.209(e)(14)).
180.209(g)).
4B, 4BA, 4BW, 4B-240ET...... 2 times service 5, 10 or 12 (see
pressure, except Sec. 180.209(e),
non-corrosive (f) and (j)).
service (see Sec.
180.209(g)).
4D, 4DA, 4DS................ 2 times service 5.
pressure.
DOT-4E...................... 2 times service 5.
pressure, except
non-corrosive
service (see Sec.
180.209(g)).
4L.......................... Test not required
8, 8AL...................... .................... 10 or 20 (See Sec.
180.209(i)).
Exemption Cylinder Foreign See current See current
cylinder (see Sec. exemption as marked exemption 5 (see
173.301(j) for restrictions on the cylinder, Sec. 180.209(k)
on use. but not less than 5/ and Sec.
3 of any service or 180.213(d)(iii)).
working pressure
marking.
------------------------------------------------------------------------
\1\ Any cylinder not exceeding two inches outside diameter and less than
two feet in length is excepted from hydrostatic test.
\2\ After January 1, 2005, DOT-3T and 3HT specification cylinders must
be inspected by a non-destructive testing method approved by the
Associate Administrator.
\3\ For cylinders not marked with a service pressure, see Sec.
173.301(e)(1) of this subchapter.
[[Page 58516]]
(2) In lieu of a hydrostatic pressure test (i.e. volumetric
expansion or proof pressure tests) as required by this section, each
DOT specification cylinder that becomes due for periodic
requalification, as specified in Table I of paragraph (a)(1) of this
section, may be requalified by using one of the following methods:
(i) Ultrasonic examination: Ultrasonic examination must be in
conformance with the requirements of the Appendix B of Subpart C of
part 178 of this subchapter and Table II of paragraph (a)(2) of this
section. Minimum wall thickness of each cylinder examined by UT must be
equal to or greater than the design minimum wall thickness. For each
cylinder, the minimum wall thickness data from the cylinder
manufacturer's inspection report must be available and used during UT
examination. An external visual inspection in accordance with the
applicable CGA pamphlet is required to be performed in conjuction with
the ultrasonic examination. The recordkeeping requirements for an
ultrasonic examination must be in accordance with Sec. 180.215. The
marking requirements for an ultrasonic examination must be in
accordance with Sec. 180.213.
Note to paragraph (a)(2)(i): The test interval for the
requalification of a nonmetric-marked DOT specification cylinder
subjected to UT examination is the same as specified in Table I of
paragraph (a)(1) of this section. The ultrasonic examination only
replaces the hydrostatic pressure test.
(ii) Other nondestructive examinations (NDE) as approved in writing
by the Associate Administrator. Table II follows:
Table II.--Criteria for Periodic Ultrasonic Examination of Non-metric Marked Cylinders
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rejected area for
reduced wall
thickness (t)
Coverage area of Coverage area of Rejectable defect Rejectable defect Rejectable pit reduced wall t =
DOT spec cylinder by cylinder by angle depth in sidewall length in sidewall size diameter (D) any value less
straight beam beam (shear wave) (% of wall (multiple of wall x depth than design min.
(longitudinal wave) thickness) thickness) wall t\1\ D =
diameter of the
cylinder
--------------------------------------------------------------------------------------------------------------------------------------------------------
3T............................. 100% of sidewall... 100% of sidewall.. 10% of Wall....... 4 times Wall...... 3 mm x \1/3\ of 161 mm\2\ or
Thickness......... Thickness......... the Designed Wall 0.002D\2\.
Thickness.
3AL (mfg. after 1989).......... 100% of sidewall... 100% of sidewall.. 15% of Wall....... 5 times Wall...... 3 mm x \1/3\ of 323 mm\2\ or
Thickness......... Thickness......... the Designed Wall 0.004D\2\.
Thickness.
3AA,3A, 3AX, 3AAX.............. 100% of sidewall... 100% of sidewall.. 15% of Wall....... 5 times Wall...... 3 mm x \1/3\ of 323 mm\2\ or
Thickness......... Thickness......... the Designed Wall 0.004D\2\.
Thickness.
4B,4BA,4BW4D,4DS,4DA........... 100% of sidewall... NA................ NA................ NA................ 3 mm x \1/3\ of 323 mm\2\ or
the Designed Wall 0.004D\2\.
Thickness.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Term wall thickness in this table means the minimum design wall thickness provided in the manufacturers inspection report.
(b) DOT-3A or 3AA cylinders. (1) A cylinder conforming to
specification DOT-3A or 3AA with a water capacity of 125 pounds or less
that is removed from any cluster, bank, group, rack, or vehicle each
time it is filled, may be requalified every ten years instead of every
five years, provided the cylinder meets all of the following--
(i) The cylinder was manufactured after December 31, 1945;
(ii) The cylinder is used exclusively for air, argon, cyclopropane,
ethylene, helium, hydrogen, krypton, neon, nitrogen, nitrous oxide,
oxygen, sulfur hexafluoride, xenon, permitted mixtures of these gases
(see Sec. 173.301(d) of this subchapter), and permitted mixtures of
these gases with up to 30 percent by volume of carbon dioxide, provided
that the gas has a dew point at or below minus (52 deg.F) at 1
atmosphere;
(iii) Before each refill, the cylinder is removed from any cluster,
bank, group, rack or vehicle and passes the hammer test specified in
CGA Pamphlet C-6;
(iv) The cylinder is dried immediately after hydrostatic testing to
remove all traces of water;
(v) The cylinder is not used for underwater breathing; and
(vi) Each cylinder is stamped with a five-pointed star at least
one-fourth of an inch high immediately following the test date.
(2) If, since the last required requalification, a cylinder has not
been used exclusively for the gases specifically identified in
paragraph (b)(1)(ii) of this section, but currently conforms with all
other provisions of paragraph (b)(1) of this section, it may be
requalified every 10 years instead of every five years, provided it is
first requalified and examined as prescribed by Sec. 173.302a(b)(2),
(3) and (4) of this subchapter.
(3) Except as specified in (b)(2) of this section, if a cylinder,
marked with a star, is filled with a compressed gas other than as
specified in paragraph (b)(1)(ii) of this section, the star following
the most recent test date must be obliterated. The cylinder must be
requalified five years from the marked test date, or prior to the first
filling with a compressed gas, if the required five-year
requalification period has passed.
[[Page 58517]]
(c) DOT 4-series cylinders. A DOT 4-series cylinder, except 4L
cylinders, that at any time shows evidence of a leak or of internal or
external corrosion, denting, bulging or rough usage to the extent that
it is likely to be weakened appreciably; or that has lost five percent
or more of its official tare weight must be requalified before being
refilled and offered for transportation. (Refer to CGA Pamphlet C-6 or
C-6.3, as applicable, regarding cylinder weakening.) After testing, the
actual tare weight must be recorded as the new tare weight.
(d) Cylinders 12 pounds or less with service pressures of 300 psi
or less. A cylinder of 12 pounds or less water capacity authorized for
service pressure of 300 psi or less must be given a complete external
visual inspection at the time periodic requalification becomes due.
External visual inspection must be in accordance with CGA Pamphlet C-6
or C-6.1. The cylinder may be hydrostatically tested without a water
jacket and without determining total and permanent expansions. The test
is successful if the cylinder, when examined under test pressure, does
not display a defect described in Sec. 180.205(i)(1)(ii) or (iii).
(e) Proof pressure test. A cylinder made in compliance with
specification DOT 4B, DOT 4BA, DOT 4BW, DOT 4E that is used exclusively
for anhydrous dimethylamine; anhydrous methylamine; anhydrous
trimethylamine; methyl chloride; liquefied petroleum gas;
methylacetylene-propadiene stabilized; or dichlorodifluoromethane,
difluoroethane, difluorochloroethane, chlorodifluoromethane,
chlorotetrafluoroethane, trifluorochloroethylene, or mixture thereof,
or mixtures of one or more with trichlorofluoromethane; and that is
commercially free from corroding components and protected externally by
a suitable corrosion-resistant coating (such as galvanizing or
painting) may be requalified every 12 years instead of every five
years. Alternatively, the cylinder may be subjected to internal
hydrostatic pressure of at least two times the marked service pressure
without determination of expansion, but this latter type of test must
be repeated every seven years after expiration of the first 12-year
period. When subjected to the latter test, the cylinder must be
carefully examined under test pressure and removed from service if a
leak or other harmful defect exists. A cylinder requalified by the
proof pressure test method must be marked after a test or an inspection
with the appropriate RIN and the date of requalification or
reinspection on the cylinder followed by an ``S''.
(f) Poisonous materials. A cylinder conforming to specification
DOT-3A, DOT-3AA, DOT-3B, DOT-4BA or DOT-4BW having a service pressure
of 300 psi or less that is used exclusively for methyl bromide, liquid;
mixtures of methyl bromide and ethylene dibromide, liquid; mixtures of
methyl bromide and chlorpicrin, liquid; mixtures of methyl bromide and
petroleum solvents, liquid; or methyl bromide and nonflammable,
nonliquefied compressed gas mixtures, liquid; that is commercially free
of corroding components, and that is protected externally by a suitable
corrosion resistant coating (such as galvanizing or painting) and
internally by a suitable corrosion resistant lining (such as
galvanizing) may be tested every 10 years instead of every five years,
provided that a visual internal and external examination of the
cylinder is conducted every five years in accordance with CGA Pamphlet
C-6. The cylinder must be examined at each filling, and rejected if a
dent, corroded area, leak or other condition indicates possible
weakness.
(g) Visual inspections. A cylinder conforming to a specification
listed in the table in this paragraph and used exclusively in the
service indicated may, instead of a periodic hydrostatic test, be given
a complete external visual inspection at the time periodic
requalification becomes due. External visual inspection must be in
accordance with CGA Pamphlet C-6 or C-6.3, as applicable. When this
inspection is used instead of hydrostatic pressure testing, subsequent
inspections are required at five-year intervals after the first
inspection. Inspections must be made only by persons holding a current
RIN and the results recorded and maintained in accordance with
Sec. 180.215. Records shall include: date of inspection (month and
year); DOT specification number; cylinder identification (registered
symbol and serial number, date of manufacture, and owner); type of
cylinder protective coating (including statement as to need of
refinishing or recoating); conditions checked (e.g., leakage,
corrosion, gouges, dents or digs in shell or heads, broken or damaged
footring or protective ring or fire damage); disposition of cylinder
(returned to service, returned to cylinder manufacturer for repairs or
condemned). A cylinder passing requalification by the external visual
inspection must be marked in accordance with Sec. 180.213.
Specification cylinders must be in exclusive service as follows:
------------------------------------------------------------------------
Cylinders made in compliance with-- Used exclusively for--
------------------------------------------------------------------------
DOT-3A, DOT-3AA, DOT-3A480X, DOT-4AA480 Anhydrous ammonia of at least
99.95% purity.
DOT-3A, DOT-3AA, DOT-3A480X, DOT-3B, Butadiene, inhibited, which is
DOT-4B, DOT-4BA, DOT-4BW. commercially free from
corroding components.
DOT-3A, DOT-3A480X, DOT-3AA, DOT-3B, Cyclopropane which is
DOT-4AA480, DOT-4B, DOT-4BA, DOT-4BW. commercially free from
corroding components.
DOT-3A, DOT-3AA, DOT-3A480X, DOT-4B, Fluorinated hydrocarbons and
DOT-4BA, DOT-4BW, DOT-4E. mixtures thereof which are
commercially free from
corroding components.
DOT-3A, DOT-3AA, DOT-3A480X, DOT-3B, Liquefied hydrocarbon gas which
DOT-4B, DOT-4BA, DOT-4BW, DOT-4E. is commercially free from
corroding components.
DOT-3A, DOT-3AA, DOT-3A480X, DOT-3B, Liquefied petroleum gas which
DOT-4B, DOT-4BA, DOT-4BW, DOT-4E. is commercially free from
corroding components.
DOT-3A, DOT-3AA, DOT-3B, DOT-4B, DOT- Methylacetylene-propadiene,
4BA, DOT-4BW, DOT-4E. stabilized, which is
commercially free from
corroding components.
DOT-3A, DOT-3AA, DOT-3B, DOT-4B, DOT- Anhydrous mono, di,
4BA, DOT-4BW. trimethylamines which are
commercially free from
corroding components.
DOT-4B240, DOT-4BW240.................. Ethyleneimine, inhibited.
------------------------------------------------------------------------
(h) Cylinders containing anhydrous ammonia. A cylinder made in
compliance with specification DOT-3A, DOT-3A480X, or DOT-4AA480 used
exclusively for anhydrous ammonia, commercially free from corroding
components, and protected externally by a suitable corrosion-resistant
coating (such as painting) may be requalified every 10 years instead of
every five years.
[[Page 58518]]
(i) Requalification of DOT 8 series cylinders. (1) Each owner of a
DOT 8 series cylinder used to transport acetylene must have the
cylinder shell and the porous filler requalified in accordance with CGA
Pamphlet C-13. Requalification must be performed in accordance with the
following schedule:
----------------------------------------------------------------------------------------------------------------
Shell (visual inspection) Porous filler requalification
requalification ------------------------------------------
Date of cylinder manufacture --------------------------------------
Initial Subsequent Initial Subsequent
----------------------------------------------------------------------------------------------------------------
Before January 1, 1991......... Before January 1, 10 years......... Before January 1, Not required.
2001. 2011.
On or after January 1, 1991.... 10 years \1\..... 10 years......... 3 to 20 years \2\ Not required.
----------------------------------------------------------------------------------------------------------------
\1\ Years from date of cylinder manufacture.
\2\ For a cylinder manufactured on or after January 1, 1991, requalification of the porous filler must be
performed no sooner than 3 years, and no later than 20 years, from the date of manufacture.
(2) Unless requalified and marked in accordance with CGA Pamphlet
C-13 before October 1, 1994, an acetylene cylinder must be requalified
by a person who holds a current RIN.
(3) If a cylinder valve is replaced, a cylinder valve of the same
weight must be used or the tare weight of the cylinder must be adjusted
to compensate for valve weight differential.
(4) The person performing a visual inspection, or requalification
must record the results as specified in Sec. 180.215.
(5) The person performing a visual inspection, or requalification
must mark the cylinder as specified in Sec. 180.213.
(j) Cylinders used as a fire extinguisher. Only DOT specification
cylinders used as fire extinguishers and meeting Special Provision 18
in Sec. 172.102(c)(1) of this subchapter may be requalified in
accordance with this paragraph (j).
(1) A DOT specification 4B, 4BA, 4B240ET or 4BW cylinder may be
tested as follows:
(i) For a cylinder with a water capacity of 12 pounds or less by
volumetric expansion test using the water jacket method or by proof
pressure test. A requalification must be performed 12 years after the
original test date and at 12-year intervals thereafter.
(ii) For a cylinder having a water capacity over 12 pounds--
(A) By proof pressure test. A requalification must be performed 12
years after the original test date and at 7-year intervals; or
(B) By volumetric expansion test using the water jacket method. A
requalification must be performed 12 years after the original test date
and at 12-year intervals thereafter.
(2) A DOT specification 3A, 3AA, or 3AL cylinder must be
requalified by volumetric expansion test using the water jacket method.
A requalification must be performed 12 years after the original test
date and at 12-year intervals thereafter.
(k) Requalification of foreign cylinders filled for export.
(1) A cylinder manufactured outside the United States, other than
as provided in Sec. 171.12a of this subchapter, that has not been
manufactured, inspected, tested and marked in accordance with part 178
of this subchapter may be filled with compressed gas in the United
States, and shipped solely for export if it meets the following
requirements, in addition to other requirements of this subchapter:
(i) It has been inspected, tested and marked (with only the month
and year of test) in conformance with the procedures and requirements
of this subpart or the Associate Administrator has authorized the
filling company to fill foreign cylinder under an alternative method of
qualification; and
(ii) It is offered for transportation in conformance with the
requirements of Sec. 173.301(l) of this subchapter.
(2) [Reserved]
Sec. 180.211 Repair, rebuilding and reheat treatment of nonmetric-
marked DOT-4 series specification cylinders.
(a) General requirements for repair and rebuilding. Any repair or
rebuilding of a DOT 4B, 4BA or 4BW cylinder must be performed by a
person holding an approval as specified in Sec. 107.805 of this
chapter. A person performing a rebuild function shall be considered a
manufacturer subject to the requirements of Sec. 178.2(a)(2) and
subpart C of part 178 of this subchapter. The person performing a
repair, rebuild, or reheat treatment must record the test results as
specified in Sec. 180.215. Each cylinder that is successfully repaired
or rebuilt must be marked in accordance with Sec. 180.213.
(b) General repair requirements. Any repair of a cylinder must be
made in accordance with the following:
(1) The repair and the inspection of the work performed must be
made in accordance with the requirements of the cylinder specification.
(2) The person performing the repair shall use the procedure,
equipment, and filler metal or brazing material as authorized by the
approval issued under Sec. 107.805 of this chapter.
(3) Welding and brazing shall be performed on an area free from
contaminants.
(4) A weld defect, such as porosity in a pressure retaining seam,
shall be completely removed before rewelding. Puddling may be used to
remove a weld defect only by the tungsten inert gas shielded arc
process.
(5) After removal of a non-pressure attachment and before its
replacement, the cylinder shall be given a visual inspection in
accordance with Sec. 180.205(f).
(6) Reheat treatment of DOT-4B, 4BA or 4BW specification cylinders
after replacement of non-pressure attachments is not required when the
total weld material does not exceed 8 inches. Individual welds must be
at least three inches apart.
(7) After repair of a DOT 4B, 4BA or 4BW cylinder, the weld area is
to be leak tested at the service pressure of the cylinder.
(8) Repair of weld defects must be free of cracks.
(9) When a non-pressure attachment with the original cylinder
specification markings is replaced, all markings must be transferred to
the attachment on the repaired cylinder.
(10) Walls, heads or bottoms of cylinders with defects or leaks in
base metal may not be repaired, but may be replaced as provided for in
paragraph (d) of this section.
(c) Additional repair requirements for 4L cylinders. (1) Repairs to
a DOT 4L cylinder are limited to the following:
(i) The removal of either end of the insulation jacket to permit
access to the cylinder, piping system, or neck tube.
(ii) The replacement of the neck tube. At least a 13 mm (0.51 inch)
piece of the original neck tube must be protruding above the cylinder's
top end. The original weld attaching the neck tube to the cylinder must
be sound and the replacement neck tube must be welded to this remaining
piece of the original neck tube.
(iii) The replacement of material such as, but not limited to, the
insulating material and the piping system within
[[Page 58519]]
the insulation space is authorized. The replacement material must be
equivalent to that used at the time of original manufacture.
(iv) Other welding procedures which are qualified by CGA Pamphlet
C-3, and not excluded by the definition of rebuild, are authorized.
(2) After repair, the cylinder must be:
(i) Pressure tested in accordance with the specifications under
which the cylinder was originally manufactured;
(ii) Leak tested before and after assembly of the insulation jacket
using a mass spectrometer detection system; and
(iii) Tested for heat conductivity requirements.
(d) General rebuilding requirements. (1) The rebuilding of a
cylinder must be made in accordance with the following requirements:
(i) The person rebuilding the cylinder must use the procedures and
equipment as authorized by the approval issued under Sec. 107.805 of
this chapter.
(ii) After removal of a non-pressure component and before
replacement of any non-pressure component, the cylinder must be
visually inspected in accordance with CGA Pamphlet C-6.
(iii) The rebuilder may rebuild a DOT 4B, 4BA or 4BW cylinder
having a water capacity of 20 pounds or greater by replacing a head of
the cylinder using a circumferential joint. When this weld joint is
located at other than an original welded joint, a notation of this
modification shall be shown on the Manufacturer's Report of Rebuilding
in Sec. 180.215(d)(2). Weld joint must be on the cylindrical section of
the cylinder.
(iv) Any welding and the inspection of the rebuilt cylinder must be
in accordance with the requirements of the applicable cylinder
specification and the following requirements:
(A) Rebuilding of any cylinder involving a joint subject to
internal pressure may only be performed by fusion welding;
(B) Welding shall be performed on an area free from contaminants;
and
(C) A weld defect, such as porosity in a pressure retaining seam,
shall be completely removed before rewelding. Puddling may be used to
remove a weld defect only by the tungsten inert gas shielded arc
process.
(2) Any rebuilt cylinder must be--
(i) Heat treated in accordance with paragraph (f) of this section;
(ii) Subjected to a volumetric expansion test on each cylinder as
specified in CGA Pamphlet C-1, paragraphs 4 or 5, and Appendices A and
B. The results of the tests must conform with the applicable cylinder
specification;
(iii) Inspected and have test data reviewed to determine
conformance with the applicable cylinder specification; and
(iv) Made of material that conforms to the specification.
Determination of conformance shall include chemical analysis,
verification, inspection and tensile testing of the replaced part.
Tensile tests must be performed on the replaced part after heat
treatment by lots defined in the applicable specification.
(3) A record of rebuilding must be completed for each cylinder
rebuilt in the format presented in Sec. 180.215(d).
(4) Rebuilding a cylinder with brazed seams is prohibited.
(5) When an end with the original cylinder specification markings
is replaced, all markings must be transferred to the rebuilt cylinder.
(e) Additional rebuilding requirements for DOT-4L cylinders. (1)
The rebuilding of a DOT 4L cylinder is:
(i) Substituting or adding material in the insulation space not
identical to that used in the original manufacture of that cylinder;
(ii) Making a weld repair not to exceed 150 mm (5.9 inches) in
length on the longitudinal seam of the cylinder or 300 mm (11.8 inches)
in length on a circumferential weld joint of the cylinder; or
(iii) Replacing the outer jacket.
(2) Reheat treatment of cylinders is prohibited.
(3) After rebuilding, each inner containment vessel must be proof
pressure tested at 2 times its service pressure. Each completed
assembly must be leak-tested using a mass spectrometer detection
system.
(f) Reheat treatment. (1) Prior to reheat treatment, each cylinder
must be given a visual inspection, internally and externally, in
accordance with Sec. 180.205(f).
(2) Cylinders must be segregated in lots for reheat treatment. The
reheat treatment and visual inspection must be performed in accordance
with the specification for the cylinders except as provided in
paragraph (f)(4) of this section.
(3) After reheat treatment, each cylinder in the lot must be
subjected to a volumetric expansion test and meet the acceptance
criteria in the applicable specification or be scrapped.
(4) After all welding and heat treatment, a test of the new weld
must be performed as required by the original specification. The test
results must be recorded in accordance with Sec. 180.215.
Sec. 180.213 Requalification markings.
(a) General. Each cylinder that has been requalified in accordance
with this subpart with acceptable results must be marked as specified
in this section. Required markings may not be altered or removed.
(b) Placement of markings. Each cylinder must be plainly and
permanently marked into the metal of the cylinder as permitted by the
applicable specification. Unless authorized by the cylinder
specification, marking on the cylinder sidewall is prohibited.
(1) Required specification markings must be legible so as to be
readily visible at all times. Markings that are becoming illegible may
be remarked on the cylinder as provided by the original specification.
The markings may be placed on any portion of the upper end of the
cylinder excluding the sidewall. No steel stamping, engraving, or
scribing may be made in the sidewall of the cylinder unless
specifically permitted in the applicable cylinder specification. A
metal plate if used, must be attached as provided by the original
specification.
(2) Markings of previous tests may not be obliterated, except when
the space originally provided for requalification dates becomes filled,
additional dates may be added as follows:
(i) All preceding test dates may be removed by peening provided
that--
(A) Permission is obtained from the cylinder owner;
(B) The minimum wall thickness is maintained in accordance with
manufacturing specifications for the cylinder; and
(C) The original manufacturing test date is not removed.
(ii) When the cylinder is fitted with a footring, additional dates
may be marked on the external surface of the footring.
(c) Marking method. The depth of markings may be no greater than
that specified in the applicable specification. The markings must be
made by stamping, engraving, scribing or any method approved in writing
by the Associate Administrator.
(1) A cylinder used as a fire extinguisher (Sec. 180.209(j)) may be
marked by using a pressure sensitive label.
(2) For a DOT 3HT cylinder, the test date and RIN must be applied
by low-stress steel stamps to a depth no greater than that prescribed
at the time of manufacture. Stamping on the sidewall is not authorized.
(d) Requalification markings. (1) Each cylinder that has
successfully passed requalification must be marked with the RIN set in
a square pattern, between the month and year of the requalification
date. The first character of the RIN must
[[Page 58520]]
appear in the upper left corner of the square pattern; the second in
the upper right; the third in the lower right, and the fourth in the
lower left. Example: A cylinder requalified in September 1998, and
approved by a person who has been issued RIN ``A123'', would be marked
plainly and permanently into the metal of the cylinder in accordance
with location requirements of the cylinder specification or on a metal
plate permanently secured to the cylinder in accordance with paragraph
(b) of this section:
[GRAPHIC] [TIFF OMITTED] TP30OC98.007
(2) Upon a written request, variation from the marking requirement
may be approved by the Associate Administrator.
(3) Exception. A cylinder subject to the requirements of
Sec. 173.301(l) of this subchapter may not be marked with a RIN.
(e) Size of markings. The size of the markings must be at least
6.35 mm (\1/4\ in.) high, except that RIN characters must be at least
3.18 mm (\1/8\ in.) high.
(f) Illustrations of the required marking information for metric-
marked cylinders and exemption cylinders after requalification are as
follows:
(1) Ultrasonic examination:
[GRAPHIC] [TIFF OMITTED] TP30OC98.008
(2) Volumetric expansion test:
[GRAPHIC] [TIFF OMITTED] TP30OC98.009
(g) Illustrations of the required marking information for
nonmetric-marked cylinders and exemption cylinders after
requalification are as follows:
(1) 5-year volumetric expansion test; 10-year volumetric expansion
test (cylinders conforming to Sec. 180.209(f) and (h)); or 12-year
volumetric expansion test(fire extinguishers conforming to
Sec. 173.309(b) of this subchapter and cylinders conforming to
Sec. 180.209(e)and Sec. 180.209(g)):
[GRAPHIC] [TIFF OMITTED] TP30OC98.010
(2) 10-year volumetric expansion test(cylinders conforming to
Sec. 180.209(b)):
[GRAPHIC] [TIFF OMITTED] TP30OC98.011
(3) Special filling limits up to 10% in excess of the marked
service pressure (cylinders conforming to Sec. 173.302a(b) of this
subchapter):
[GRAPHIC] [TIFF OMITTED] TP30OC98.012
(4) Proof pressure test (fire extinguishers conforming to
Sec. 173.309(b) of this subchapter and cylinders conforming to
Sec. 180.209(e)):
[GRAPHIC] [TIFF OMITTED] TP30OC98.013
(5) 5-year external visual inspection (cylinders conforming to
Sec. 180.209(g)):
[GRAPHIC] [TIFF OMITTED] TP30OC98.014
(6) Requalification after a repair procedure and volumetrically
tested (cylinders conforming to Sec. 180.211):
[GRAPHIC] [TIFF OMITTED] TP30OC98.015
(7) Requalification after a repair procedure and proof pressure
tested (cylinders conforming to Sec. 180.211):
[GRAPHIC] [TIFF OMITTED] TP30OC98.016
(8) Requalification after a rebuilding procedure:
[GRAPHIC] [TIFF OMITTED] TP30OC98.017
(9) DOT 8 series cylinder shell reinspection only:
[GRAPHIC] [TIFF OMITTED] TP30OC98.018
(10) DOT 8 series cylinder shell and porous filler reinspection:
[GRAPHIC] [TIFF OMITTED] TP30OC98.019
Sec. 180.215 Reporting and record retention requirements.
(a) Facility records. A person who requalifies, repairs or rebuilds
cylinders shall maintain the following records where the
requalification is performed:
(1) Current RIN issuance letter;
(2) If the RIN has expired and renewal is pending, a copy of the
renewal request;
(3) Copies of notifications to Associate Administrator required
under Sec. 107.805 of this subchapter;
(4) Current copies of those portions of this subchapter that apply
to its cylinder requalification and marking activities at that
location;
(5) Current copies of all exemptions governing exemption cylinders
requalified or marked by the requalifier at that location; and
(6) The information contained in each applicable CGA or ASTM
standard incorporated by reference in Sec. 171.7 of this subchapter
that applies to the requalifier's activities. This information must be
the same as contained in the edition incorporated by reference in
Sec. 171.7 of this subchapter.
(b) Requalification records. Daily records of visual inspection,
pressure test, and ultrasonic examination, as applicable, must be
maintained by the person who performs the requalification until either
the expiration of the requalification period or until the cylinder is
again requalified, whichever occurs first. A single date may be used
for each test sheet, provided each test on the sheet was conducted on
that date. Ditto marks or a solid vertical line may be used to indicate
repetition of the preceding entry for the following entries: date;
actual dimensions; if present, manufacturer's name or symbol; if
present, owner's name or symbol and test operator. Blank spaces may not
be used to indicate repetition of a prior entry. The records must
include the following information:
(1) Pressure test records. For each test to demonstrate
calibration, the date; serial number of the calibrated cylinder;
calibration test pressure; total, elastic and permanent expansions; and
legible identification of test operator. The test operator must be able
to demonstrate that the results of the daily calibration verification
correspond to the hydrostatic tests that were performed on that day.
The daily verification of calibration(s) may be recorded on the same
sheets as, and with, test records for that date.
(2) Pressure test and visual inspection records. The date of
requalification; serial number; DOT specification or exemption number;
marked pressure; actual dimensions; if present,
[[Page 58521]]
manufacturer's name or symbol; if present, owner's name or symbol;
result of visual inspection; actual test pressure; total, elastic and
permanent expansions; percent permanent expansion; disposition, with
reason for any repeated test, rejection or condemnation; and legible
identification of test operator. For each cylinder marked pursuant to
Sec. 173.302a(b)(5) of this subchapter, the test sheet must indicate
the method by which any average or maximum wall stress was computed.
Records must be kept for all completed, as well as unsuccessful tests.
The entry for a second test under CGA Pamphlet C-1 after a failure to
hold test pressure, must indicate the date of the earlier inspection or
test.
(3) Wall stress. Calculations of average and maximum wall stress
pursuant to Sec. 173.302a(b)(3) of this subchapter, if performed;
(4) Calibration certificates. The most recent certificate of
calibration must be maintained for each calibrated cylinder.
(5) Ultrasonic examination records. The information prescribed in
ASTM E 797 or ASTM E 213 as applicable.
(c) Repair, rebuilding or reheat treatment records. (1) Records
covering welding or brazing repairs, rebuilding or reheat treating
shall be retained for a minimum of fifteen years by the approved
facility.
(2) A record for rebuilding, in accordance with Sec. 180.211(d),
must be completed for each cylinder rebuilt. The record must be clear,
legible, and contain the following information:
Cylinder Identification
Original Manufacturer--------------------------------------------------
Cylinder Specification Number and Service
Pressure---------------------------------------------------------------
Cylinder Serial Number-------------------------------------------------
Date at Original Manufacturer------------------------------------------
Other Identification Marks---------------------------------------------
Chemical Analysis of Replacement Parts
Parts Being Replaced---------------------------------------------------
Heat Identification----------------------------------------------------
Steel Manufactured by--------------------------------------------------
Analysis Performed by--------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
C P S Si Mn Ni Cr Mo Cu Al Zn
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
Record of Physical Test of Replacement Parts
----------------------------------------------------------------------------------------------------------------
Elongation in Reduction in area
Yield PSI Tensile PSI inches % Weld bend Weld tensile
----------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------
Record of Volumetric Expansion Test
Calculated volumetric capacity of the cylinder being rebuilt-
________________ lbs.
------------------------------------------------------------------------
Percent of
Actual test Total Permanent total to Volumetric
pressure expansion expansion permanent capacity
------------------------------------------------------------------------
------------------------------------------------------------------------
(Permanent expansion may not exceed 10% of the total expansion)
(Volumetric capacity of a rebuilt cylinder must be within plus or
minus 3% at the calculated capacity)
I certify that this rebuilt cylinder is accurately represented
by the data above and complies with all of the requirements in
Subchapter C of 49 CFR.
Repair Technician------------------------------------------------------
Date-------------------------------------------------------------------
Company Representative-------------------------------------------------
Date-------------------------------------------------------------------
Issued in Washington D.C. on October 15, 1998, under authority
delegated in 49 CFR Part 106, Appendix A.
Alan I. Roberts,
Associate Administrator for Hazardous Materials Safety.
[FR Doc. 98-28118 Filed 10-26-98; 10:46 am]
BILLING CODE 4910-60-P