Firefighters are trained to use communications equipment to receive alarms, give and receive commands, request assistance, and report on conditions. Since firefighters from different agencies routinely provide mutual aid to each other, and routinely operate at where other emergency services are present, it is essential to have structures in place to establish a unified chain of command, and share information between agencies.
The U.S. Federal Emergency Management Agency (FEMA) has established a National Incident Management System. One component of this system is the Incident Command System.
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