The Emergency Alert System replaced the Emergency Broadcast System in 1997. The EAS is used as an early warning system to alert citizens of possible dangers both in their local area and nationwide.
The Emergency Alert System is used to warn residents about dangerous weather, potential attacks by enemy combatants and other threats. AMBER alerts are also a service provided by the EAS. EAS alerts are broadcast via television, radio and wireless devices. When an EAS alert is triggered, a tone is transmitted before the information is provided. The message generally includes the warning or notice and, if necessary, any instructions listeners need to follow to protect themselves.