How many air horn blasts indicate an evacuation order within a fire building?

Three one-second blasts of the air horn are the established signal for an evacuation order within a fire building. This specific signal is critical for ensuring that all personnel are aware of the need to evacuate promptly and safely from a potentially dangerous environment. The use of three distinct blasts minimizes confusion and enhances the urgency of the evacuation order, as it is distinct from other signals used in operations and communications.

The protocol for signaling an evacuation is designed to be clear and unambiguous to ensure that all members respond appropriately, as time is often of the essence in fire incidents. Firefighters are trained to recognize this auditory cue in the midst of high-stress situations, facilitating a swift and coordinated response to safeguard lives.