Glossary of Terms and Acronyms
Activation: The initiation of the EAS by transmission of the EAS codes.
ASCII: A standard set of text characters with numerical equivalents.
Attention Signal: An eight to twenty-five second two tone signal (853 and 960 Hz) used as an audio alert.
Audio Frequency Shift Keying (AFSK): A digital modulation technique that uses two shifting audio frequencies to transmit binary data.
Authenticator Word Lists: A list of words that federal officials send prior to official EAS national activation; used to substantiate the information being sent.
Automatic Interruption: The automatic encoding and transmission of EAS codes for preselected events.
Baud Rate: The speed of data transmitted, equal to number of elements sent per second (equal to bits per second if a bit is the element).
Bit Rate: The speed of binary data transmitted, equal to the number of digital bits sent per second.
Certification: An equipment authorization issued by the FCC based on representations and test data submitted by the applicant for equipment designated to be operated without individual license under Parts 15 and 18 of the rules.
Class D FM Station: A station whose output power is 10 watts or less.
Decoder (EAS): An electronic device used by EAS participants to receive EAS alerts.
Decoder (Two-Tone): An electronic device that alerts operators to the reception of the two-tone signal.
Emergency Action Notification (EAN): The message for national EAS alerts.
Emergency Action Termination (EAT): The message for national EAS alert termination.
Encoder (EAS): An electronic device used by EAS participants to originate EAS alerts by creating the EAS codes for transmission to other participants and the public.
Encoder (Two-Tone): An electronic device that produces the two-tone signal.
EOM Code: In ASCII form >NNNN=, this burst of data, sent three times signifies the end of an EAS message and EAS activation.
Event Codes: A three character ASCII code in the EAS headers that denotes the type of emergency event.
Federal Emergency Management Agency (FEMA): One of the three federal agencies that administers EAS.
FIPS Number: A five character ASCII code in the EAS headers that represent those counties affected by an EAS activation, as defined by the Federal Information Processing System. Each state and territory has their own five digit number.
Header Code: A single string of intelligent digital EAS ASCII data that includes the originator, event, location, time period, and other basic information concerning an emergency; three header codes precede the voice warning message.
Julian Calendar: A method of specifying the date by the number of days which have passed since the first day of January in a year.
Key Source: A source which is central to the dissemination of emergency alerts and information, such as an NP, SP, or LP broadcast station or cable system.
Local Primary (LP): A key source within an EAS local area that is the primary source of EAS programming for that area.
Location Code: An ASCII code in an EAS header that specifies the location of an emergency utilizing the five character FIPS code of a state and county, and a sixth character to designate nine divisions of a county.
Low Power Television (LPTV): A television signal translator station which may also originate programming.
Mapbook: A list of broadcast stations and cable systems and their EAS designation delineated by state and local area for use by other stations to determine the best source of EAS monitoring; an FCC generated attachment to every state plan.
Mark Frequency: The audio frequency of AFSK modulation that corresponds to a digital bit of one (1)the mark frequency of EAS codes is 6250/3 Hz, or approximately 2083.33 Hz.
Monitoring Assignment: The off-air broadcast or cable sources of EAS activation=s and programming as given in the FCC Mapbook and the state plans.
National Information Center (NIC): A source of official federal government information.
National Oceanic and Atmospheric Administration (NOAA): One of the three federal agencies that participate in EAS.
National Primary (NP): A primary source of Presidential or other national EAS activation=s and programming, including broadcast stations involved with the PEP system and EAN Networks:
National Weather Service (NWS): An operation of NOAA that is directly responsible for issuing local weather-related emergency alerts and warnings in addition to day-to-day forecasts and other weather activities.
NOAA Weather Radio (NWR): A service of the National Weather Service that provides to a local area continuous broadcasts of the latest weather information and any weather-related emergency warnings using one of seven VHF radio channels.
Non-participating National (NN): An EAS source (usually a broadcast station) that has elected not to participate in the National-level EAS and removes its carrier from the air if a national-level activation occurs.
Operating Handbook: A document issued by the FCC that instructs broadcast station and cable personnel of the actions they must take during an activation of EAS.
Operator Interruption: The transmission of the EAS activation which has been manually initiated by broadcast station or cable system personnel.
Originator Code: A three character ASCII code in an EAS header which denotes the source of an activation.
Participating National (PN): Broadcast stations, cable systems, or MDS stations which monitor primary sources of EAS programming and directly feed emergency alerts to the public.
Pre-selected Code: An EAS event which the operator of EAS equipment has chosen to be automatically encoded and retransmitted upon reception.
Primary Entry Point (PEP): Key broadcast stations throughout the U.S. which together can provide national emergency information in the event that the primary national alerting methods are inoperable.
Program Priorities: The precedence of the information that must be transmitted during an EAS activation, namely national, local, and state activation=s in that order.
Radio Broadcast Data System (RBDS): A defined protocol for data that is transmitted on the 57 kHz subcarrier of FM radio broadcast stations utilized mainly by consumer devices equipped to receive it.
Required Monthly Test (RMT): A coordinated monthly test of EAS operations involving the full receiving and transmission of EAS codes, Attention Signal, EAS test programming, and EAS EOM codes.
Required Weekly Test (RWT): An independent weekly test of EAS equipment only involving the decoding and encoding of EAS header codes and EOM codes.
RS-232: A common interface standard which specifies the mechanical connection, electrical signals, and the function of the signals carried across the interface.
Space Frequency: The audio frequency of AFSK modulation that corresponds to a digital bit of zero (0); the space frequency of EAS codes is 6250/4 Hz, or 1562.5 Hz.
State/Local Plan: A document that details monitoring assignments, actions to be taken in emergency activation=s, and other guidance for broadcasters and cable personnel in use of the EAS.
State Primary (SP): A primary source of EAS state programming which can originate with a Governor or designated representative, such as a state=s emergency operations officer.
State Relay (SR): An entity which receives and retransmits EAS activation=s in a State Relay Network to assist in bringing a state activation to all EAS local areas of a state.
State Relay Network: A system of facilities used to distribute state EAS activation=s and programming across a state.
Subcarrier: An inaudible portion of the broadcast signal that is added to the program signal of the AM, FM, or TV sound and these may include 57 kHz, 67 kHz, 69 kHz, and 92 kHz subcarriers
Subsidiary Communications Services: A subcarrier of television and FM stations providing a second audio programming source.
UTC: Coordinated Universal Time, the world-wide common time standard that is used in EAS headers for time stamp.
Valid Code: An EAS header which has been matched bit-for-bit with one of two other received headers thereby checked for validity.
Weather Radio Specific Area Message Encoder (WRSAME): A device used by National Weather Service to broadcast WRSAME data on the National Weather Radio for day-to-day forecasts and weather-related emergency announcements.
AFSK: Audio Frequency Shift Keying
AM: Amplitude Modulation
AP: Associated Press
ASCII: American Standard Code for Information Interchange
BPS: Bits per Second
CATV: Cable Television
CFR: Code of Federal Regulations
EBS: Emergency Broadcast System
EOC: Emergency Operations Center
EOM: End of Message
FCC: Federal Communications Commission
FEMA: Federal Emergency Management Agency
FIPS: Federal Information Processing Standards
FM: Frequency Modulation
LP: Local Primary
LPTV: Low Power Television
MDS: Multi point Distribution System
NAC: National Advisory Committee
NAWAS: National Warning System
NIC: National Information Center
NN: Non-participating National
NOAA: National Oceanic and Atmospheric Administration
NP: National Primary
NWR: NOAA Weather Radio
NWS: National Weather Service
LECC: Local Area Emergency Communications Committee
PEP: Primary Entry Point
PN: Participating National
SAME: Specific Area Message Encoding
SECC: State Emergency Communications Committee
SP: State Primary
SR: State Relay
UTC: Coordinated Universal Time
VHF: Very High Frequency
WHCA: White House Communications Agency
WRSAME: Weather Radio Specific Area Message Encoding