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alert - warning

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Emergency Alert System

The Emergency Alert System (EAS) is a national public warning system that requires radio and TV broadcasters, cable TV, wireless cable systems, satellite and wireline operators to provide the President with capability to address the American people within 10 minutes during a national emergency.

Broadcast, cable, and satellite operators are the stewards of this important public service in close partnership with state, local, tribal, and territorial authorities.

FEMA, in partnership with the Federal Communications Commission and National Oceanic and Atmospheric Administration, is responsible for implementing, maintaining and operating the EAS at the federal level.

Emergency Alert System Details

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Messages can interrupt radio and television to broadcast emergency alert information.

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Messages cover a large geographic footprint. Emergency message audio/text may be repeated twice, but EAS activation interrupts programming only once, then regular programming continues.

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Messages can support full message text for screen crawl/display, audio attachments in mp3 format, and additional languages.

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It is important for authorities who send EAS messages to have a relationship with their broadcasters to understand what will be aired via radio, TV and cable based on their policies. Policies vary from station to station.

Tests of the Emergency Alert System

FEMA is also responsible for national-level EAS tests and exercises.

National-level tests of EAS evaluate the readiness of the system and our national alerting capability in the absence of internet connectivity.

 Why Do a National EAS Test?

  • The IPAWS Modernization Act of 2015 (Public Law 114-143) requires FEMA  to conduct, not less than once every three years, a nationwide EAS test. The Act, which became law in April 2016, requires FEMA to help ensure that under all conditions the President can alert and warn the civilian population in areas endangered by natural disasters, acts of terrorism and other man-made disasters or threats to public safety.
  • The testing process is designed to evaluate the effectiveness of the IPAWS Open Platform for Emergency Networks and assess the operational readiness of the infrastructure for distribution of a national message and determine whether technological improvements are needed.
  • Testing will help ensure an effective and reliable system exists to provide timely and accurate alerts to the public. After each test, an after-action report and improvement plan is created and incorporated into future testing to ensure continual advancement of alert and warning capabilities.
  • The national tests encourage communication and strengthen relationships between the broadcast, wireless and emergency management communities.

Before a national EAS test is conducted, there is significant coordination with radio and television broadcasters, cable systems, satellite radio and television providers, wireline video providers, and emergency managers.

Nationwide Tests

On Aug. 7, 2019 FEMA, in coordination with the FCC, conducted the fifth nationwide test of the EAS. Previous EAS national tests were conducted in November 2011, September 2016 and 2017, and October 2018, in collaboration with the Federal Communications Commission, radio and television stations,, and emergency management officials.

The audio test message was similar to regular monthly EAS test messages with which the public is familiar: “This is a test of the national Emergency Alert System.”  The intent of 2019’s test was to evaluate the readiness of the national alerting capability in the absence of internet connectivity.