Goto Section: 11.21 | 11.32 | Table of Contents
FCC 11.31
Revised as of October 2, 2015
Goto Year:2014 |
2016
§ 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. Unused characters must be ASCII space characters. 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. 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 + TTTTpJJJHHMM-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 is 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 codes described in the American National Standards
Institute (ANSI) standard, ANSI INCITS 31-2009 (“Information
technology—Codes for the Identification of Counties and Equivalent Areas of
the United States, Puerto Rico, and the Insular Areas”). 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 EAS Participant, 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
EAS Participant 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.
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.
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.
^1Effective May 16, 2002, analog radio and television broadcast stations,
analog 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. EAS
Participants that install or replace their EAS equipment after February 1,
2004 must install equipment that is capable of receiving and transmitting
these event codes.
(f) The All U.S., State, Territory and Offshore (Marine Area) ANSI number
codes (SS) are as follows. County ANSI numbers (CCC) are contained in the
State EAS Mapbook.
ANSI No.
All U.S. 00
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 from Canadian border
to Mexican border 57
North Pacific Ocean near Alaska, and along Alaska coastline, including the
Bering Sea and the Gulf of Alaska 58
Central Pacific Ocean, including Hawaiian waters 59
South Central Pacific Ocean, including American Samoa waters 61
Western Pacific Ocean, including Mariana Island waters 65
Western North Atlantic Ocean, and along U.S. East Coast, from Canadian
border south to Currituck Beach Light, N.C. 73
Western North Atlantic Ocean, and along U.S. East Coast, south of Currituck
Beach Light, N.C., following the coastline into Gulf of Mexico to Bonita
Beach, FL., including the Caribbean 75
Gulf of Mexico, and along the U.S. Gulf Coast from the Mexican border to
Bonita Beach, FL 77
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
^1Effective May 16, 2002, analog radio and television broadcast stations,
analog 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. EAS Participants that install or 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; 69 FR 72031 , Dec. 10, 2004; 70 FR 71033 , Nov.
25, 2005; 77 FR 16701 , Mar. 22, 2012; 80 FR 37174 , June 30, 2015]
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Goto Year: 2014 |
2016
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