Goto Section: 11.21 | 11.32 | Table of Contents
FCC 11.31
Revised as of October 1, 2011
Goto Year:2010 |
2012
§ 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+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 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
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
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 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 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]
Goto Section: 11.21 | 11.32
Goto Year: 2010 |
2012
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