Most people are familiar with the Emergency Alert System because of test broadcasts that interrupt their favorite radio station programming or TV show with jarring tones and the announcement "This is a test."
While those interruptions can be inconvenient, they are important and can carry lifesaving warnings about hazardous conditions in the local broadcast area.
EAS is designed to allow government authorities to notify the public of impending emergencies via voluntary cooperation of the broadcast media. The federal government requires broadcast stations to carry announcements by the president during times of national emergency, but all other EAS functions are voluntary, carried out as part of the industry’s public service effects.
In New Hampshire EAS is operated by the State Emergency Communications Committee, which is made up of representatives of the broadcast industry and public safety agencies, including New Hampshire Homeland Security and Emergency Management. The committee is chaired by veteran New Hampshire broadcaster Ed Brouder.
The system has three origination points: New Hampshire HSEM Communications, New Hampshire State Police Communications and the National Weather Service Office in Gray, Maine. All three origination points transmit test messages, but the National Weather Service is the most frequent user of the system for actual alerts.
From the origination points, the EAS signal is carried via microwave to Mt. Washington, the Veterans Administration Hospital in Manchester, Mt. Kearsarge in Merrimack County and Highland Hill in Cheshire County.
From the microwave relays, the signal is carried to seven primary stations: WHOM in Portland, Maine; WOKQ in Dover, WMUR-TV in Manchester, WGIR-FM in Manchester, WKNE-FM in Keene, WHDQ-FM in Claremont and WLNH-FM in Laconia. Other stations and cable TV systems monitor one of the primary stations and rebroadcast the signal from it. In all, five TV stations and 84 radio stations, and all of the state’s cable TV franchises, will broadcast a statewide message.
Many broadcast stations and all cable TV systems today are automated and designed for unattended operation. EAS is designed to operate using automated equipment. Those tones that start and end each message are designed to get the attention of human listeners, but also to trigger EAS receivers and relay the message.
As indicated above, the National Weather Service is the most frequent user of EAS. That is appropriate because most of the potential emergencies in New Hampshire are weather-related. Severe winter storms, floods, thunderstorms, hurricanes and tornadoes can be life threatening and the weather service (link to weather section) can provide advance warning. But EAS could be used with any type of natural or manmade emergency. For example, EAS is an integral part of the warning system for the Seabrook Station nuclear power plant.
The newest use for EAS is for child abduction emergencies, known in many states as Amber Alerts. Child abduction alerts are intended to enlist the public’s help in locating a kidnapped child in cases where the child’s life is believed to be in danger. According to New Hampshire’s Child Abduction Alert protocols, the system can only be used if the child being sought is 17 years old or less, there is reason to believe the child’s life is in danger and there is specific information available to identify the child or alleged abductor, such as person descriptions or a vehicle license number.
The request to use the system must come from the investigating police department and be approved by a State Police supervisor. Child Abduction Alerts have been available in New Hampshire since 2003.
The Federal Communications Commission is currently continuing technological improvements to the Emergency Alert System.