Radio Amateur Civil Emergency Service

The Radio Amateur Civil Emergency Service (RACES) is an emergency radio service authorized in Part 97.407 of the Federal Communications Commission (FCC) rules and regulations governing amateur radio in the United States. The concept of a standby "Radio Amateur Civil Emergency Service" to replace the conventional "Amateur Radio Service" during wartime was developed in 1952 as result of input from the American Radio Relay League and the Department of the Army's Office of Civil Defense.

Source: Wikipedia — Radio Amateur Civil Emergency Service (CC BY-SA 4.0)