[Title 47 CFR 11.31]
[Code of Federal Regulations (annual edition) - October 1, 2004 Edition]
[Title 47 - TELECOMMUNICATION]
[Chapter I - FEDERAL COMMUNICATIONS COMMISSION]
[Subchapter A - GENERAL]
[Part 11 - EMERGENCY ALERT SYSTEM (EAS)]
[Subpart B - Equipment Requirements]
[Sec. 11.31 - EAS protocol.]
[From the U.S. Government Printing Office]


47TELECOMMUNICATION12004-10-012004-10-01false11.31Sec. 11.31TELECOMMUNICATIONFEDERAL COMMUNICATIONS COMMISSIONGENERALEMERGENCY ALERT SYSTEM (EAS)Equipment Requirements
Sec. 11.31  EAS protocol.

    (a) The EAS uses a four part message for an emergency activation of 
the EAS. The four parts are: Preamble and EAS Header Codes; audio 
Attention Signal; message; and, Preamble and EAS End Of Message (EOM) 
Codes.
    (1) The Preamble and EAS Codes must use Audio Frequency Shift Keying 
at a rate of 520.83 bits per second to transmit the codes. Mark 
frequency is 2083.3 Hz and space frequency is 1562.5 Hz. Mark and space 
time must be 1.92 milliseconds. Characters are ASCII seven bit 
characters as defined in ANSI X3.4-1977 ending with an eighth null bit 
(either 0 or 1) to constitute a full eight-bit byte.
    (2) The Attention Signal must be made up of the fundamental 
frequencies of 853 and 960 Hz. The two tones must be transmitted 
simultaneously. The Attention Signal must be transmitted after the EAS 
header codes.
    (3) The message may be audio, video or text.
    (b) The ASCII dash and plus symbols are required and may not be used 
for any other purpose. FM or TV call signs must use a slash ASCII 
character number 47 (/) in lieu of a dash.
    (c) The EAS protocol, including any codes, must not be amended, 
extended or abridged without FCC authorization.

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The EAS protocol and message format are specified in the following 
representation.

Examples are provided in FCC Public Notices.

[PREAMBLE]ZCZC-ORG-EEE-PSSCCC+TTTT-JJJHHMM-LLLLLLLL-(one second pause)
[PREAMBLE]ZCZC-ORG-EEE-PSSCCC+TTTT-JJJHHMM-LLLLLLLL-(one second pause)
[PREAMBLE]ZCZC-ORG-EEE-PSSCCC+TTTT-JJJHHMM-LLLLLLLL-(at least a one 
second pause)
(transmission of 8 to 25 seconds of Attention Signal)
(transmission of audio, video or text messages)
(at least a one second pause)
[PREAMBLE]NNNN (one second pause)
[PREAMBLE]NNNN (one second pause)
[PREAMBLE]NNNN (at least one second pause)

    [PREAMBLE] This is a consecutive string of bits (sixteen bytes of AB 
hexadecimal [8 bit byte 10101011]) sent to clear the system, set AGC and 
set asynchronous decoder clocking cycles. The preamble must be 
transmitted before each header and End Of Message code.
    ZCZC--This is the identifier, sent as ASCII characters ZCZC to 
indicate the start of ASCII code.
    ORG--This is the Originator code and indicates who originally 
initiated the activation of the EAS. These codes are specified in 
paragraph (d) of this section.
    EEE--This is the Event code and indicates the nature of the EAS 
activation. The codes are specified in paragraph (e) of this section. 
The Event codes must be compatible with the codes used by the NWS 
Weather Radio Specific Area Message Encoder (WRSAME).
    PSSCCC--This the Location code and indicates the geographic area 
affected by the EAS alert. There may be 31 Location codes in an EAS 
alert. The Location code uses the Federal Information Processing 
Standard (FIPS) numbers as described by the U.S. Department of Commerce 
in National Institute of Standards and Technology publication FIPS PUB 
6-4. Each state is assigned an SS number as specified in paragraph (f) 
of this section. Each county and some cities are assigned a CCC number. 
A CCC number of 000 refers to an entire State or Territory. P defines 
county subdivisions as follows: 0 = all or an unspecified portion of a 
county, 1 = Northwest, 2 = North, 3 = Northeast, 4 = West, 5 = Central, 
6 = East, 7 = Southwest, 8 = South, 9 = Southeast. Other numbers may be 
designated later for special applications. The use of county 
subdivisions will probably be rare and generally for oddly shaped or 
unusually large counties. Any subdivisions must be defined and agreed to 
by the local officials prior to use.
    +TTTT--This indicates the valid time period of a message in 15 
minute segments up to one hour and then in 30 minute segments beyond one 
hour; i.e., +0015, +0030, +0045, +0100, +0430 and +0600.
    JJJHHMM--This is the day in Julian Calendar days (JJJ) of the year 
and the time in hours and minutes (HHMM) when the message was initially 
released by the originator using 24 hour Universal Coordinated Time 
(UTC).
    LLLLLLLL--This is the identification of the broadcast station, cable 
system, MDS/MMDS/ITFS station, NWS office, etc., transmitting or 
retransmitting the message. These codes will be automatically affixed to 
all outgoing messages by the EAS encoder.
    NNNN--This is the End of Message (EOM) code sent as a string of four 
ASCII N characters.

    (d) The only originator codes are:

------------------------------------------------------------------------
                  Originator                            ORG Code
------------------------------------------------------------------------
Broadcast station or cable system.............  EAS
Civil authorities.............................  CIV
National Weather Service......................  WXR
Primary Entry Point System....................  PEP
------------------------------------------------------------------------

    (e) The following Event (EEE) codes are presently authorized:

------------------------------------------------------------------------
             Nature of Activation                      Event Codes
------------------------------------------------------------------------
National Codes (Required):
Emergency Action Notification (National only).  EAN
Emergency Action Termination (National only)..  EAT
National Information Center...................  NIC
National Periodic Test........................  NPT
Required Monthly Test.........................  RMT
Required Weekly Test..........................  RWT
State and Local Codes (Optional):
Administrative Message........................  ADR
Avalanche Warning.............................  AVW\1\
Avalanche Watch...............................  AVA\1\
Blizzard Warning..............................  BZW
Child Abduction Emergency.....................  CAE\1\
Civil Danger Warning..........................  CDW\1\
Civil Emergency Message.......................  CEM
Coastal Flood Warning.........................  CFW\1\
Coastal Flood Watch...........................  CFA\1\
Dust Storm Warning............................  DSW\1\
Earthquake Warning............................  EQW\1\
Evacuation Immediate..........................  EVI
Fire Warning..................................  FRW\1\
Flash Flood Warning...........................  FFW
Flash Flood Watch.............................  FFA
Flash Flood Statement.........................  FFS
Flood Warning.................................  FLW
Flood Watch...................................  FLA
Flood Statement...............................  FLS
Hazardous Materials Warning...................  HMW\1\
High Wind Warning.............................  HWW
High Wind Watch...............................  HWA
Hurricane Warning.............................  HUW
Hurricane Watch...............................  HUA
Hurricane Statement...........................  HLS
Law Enforcement Warning.......................  LEW\1\

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Local Area Emergency..........................  LAE\1\
Network Message Notification..................  NMN\1\
911 Telephone Outage Emergency................  TOE\1\
Nuclear Power Plant Warning...................  NUW\1\
Practice/Demo Warning.........................  DMO
Radiological Hazard Warning...................  RHW\1\
Severe Thunderstorm Warning...................  SVR
Severe Thunderstorm Watch.....................  SVA
Severe Weather Statement......................  SVS
Shelter in Place Warning......................  SPW\1\
Special Marine Warning........................  SMW\1\
Special Weather Statement.....................  SPS
Tornado Warning...............................  TOR
Tornado Watch.................................  TOA
Tropical Storm Warning........................  TRW\1\
Tropical Storm Watch..........................  TRA\1\
Tsunami Warning...............................  TSW
Tsunami Watch.................................  TSA
Volcano Warning...............................  VOW\1\
Winter Storm Warning..........................  WSW
Winter Storm Watch............................  WSA
------------------------------------------------------------------------
\1\ Effective May 16, 2002, broadcast stations, cable systems and
  wireless cable systems may upgrade their existing EAS equipment to add
  these event codes on a voluntary basis until the equipment is
  replaced. All models of EAS equipment manufactured after August 1,
  2003 must be capable of receiving and transmitting these event codes.
  Broadcast stations, cable systems and wireless cable systems which
  replace their EAS equipment after February 1, 2004 must install
  equipment that is capable of receiving and transmitting these event
  codes.

    (f) The State, Territory and Offshore (Marine Area) FIPS number 
codes (SS) are as follows. County FIPS numbers (CCC) are contained in 
the State EAS Mapbook.

------------------------------------------------------------------------
                                                           FIPS
------------------------------------------------------------------------
State:
  AL.....................................................          01
  AK.....................................................          02
  AZ.....................................................          04
  AR.....................................................          05
  CA.....................................................          06
  CO.....................................................          08
  CT.....................................................          09
  DE.....................................................          10
  DC.....................................................          11
  FL.....................................................          12
  GA.....................................................          13
  HI.....................................................          15
  ID.....................................................          16
  IL.....................................................          17
  IN.....................................................          18
  IA.....................................................          19
  KS.....................................................          20
  KY.....................................................          21
  LA.....................................................          22
  ME.....................................................          23
  MD.....................................................          24
  MA.....................................................          25
  MI.....................................................          26
  MN.....................................................          27
  MS.....................................................          28
  MO.....................................................          29
  MT.....................................................          30
  NE.....................................................          31
  NV.....................................................          32
  NH.....................................................          33
  NJ.....................................................          34
  NM.....................................................          35
  NY.....................................................          36
  NC.....................................................          37
  ND.....................................................          38
  OH.....................................................          39
  OK.....................................................          40
  OR.....................................................          41
  PA.....................................................          42
  RI.....................................................          44
  SC.....................................................          45
  SD.....................................................          46
  TN.....................................................          47
  TX.....................................................          48
  UT.....................................................          49
  VT.....................................................          50
  VA.....................................................          51
  WA.....................................................          53
  WV.....................................................          54
  WI.....................................................          55
  WY.....................................................          56
Terr.:
  AS.....................................................          60
  FM.....................................................          64
  GU.....................................................          66
  MH.....................................................          68
  MH.....................................................          68
  PR.....................................................          72
  PW.....................................................          70
  UM.....................................................          74
  VI.....................................................          78
Offshore (Marine Areas) \1\:
  Eastern North Pacific Ocean, and along U.S. West Coast           57
   from Canadian border to Mexican border................
  North Pacific Ocean near Alaska, and along Alaska                58
   coastline, including the Bering Sea and the Gulf of
   Alaska................................................
  Central Pacific Ocean, including Hawaiian waters.......          59
  South Central Pacific Ocean, including American Samoa            61
   waters................................................
  Western Pacific Ocean, including Mariana Island waters.          65
  Western North Atlantic Ocean, and along U.S. East                73
   Coast, from Canadian border south to Currituck Beach
   Light, N.C............................................
  Western North Atlantic Ocean, and along U.S. East                75
   Coast, south of Currituck Beach Light, N.C., following
   the coastline into Gulf of Mexico to Bonita Beach,
   FL., including the Caribbean..........................
  Gulf of Mexico, and along the U.S. Gulf Coast from the           77
   Mexican border to Bonita Beach, FL....................
  Lake Superior..........................................          91
  Lake Michigan..........................................          92
  Lake Huron.............................................          93
  Lake St. Clair.........................................          94
  Lake Erie..............................................          96
  Lake Ontario...........................................          97
  St. Lawrence River above St. Regis.....................         98
------------------------------------------------------------------------
\1\ Effective May 16, 2002, broadcast stations, cable systems and
  wireless cable systems may upgrade their existing EAS equipment to add
  these marine area location codes on a voluntary basis until the
  equipment is replaced. All models of EAS equipment manufactured after
  August 1, 2003, must be capable of receiving and transmitting these
  marine area location codes. Broadcast stations, cable systems and
  wireless cable systems which replace their EAS equipment after
  February 1, 2004, must install equipment that is capable of receiving
  and transmitting these location codes.


[59 FR 67092, Dec. 28, 1994, as amended at 60 FR 55999, Nov. 6, 1995; 61 
FR 54952, Oct. 23, 1996; 63 FR 29663, June 1, 1998; 67 FR 18508, Apr. 
16, 2002; 67 FR 77174, Dec. 17, 2002]

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