What is the standard air horn evacuation signal sequence used by RVC and CAL/Fire?

• A. Continuous air horn for approximately fifty seconds.
• B. One thirty-second air horn blast from all apparatus.
• C. Two short blasts followed by ten seconds of silence.
• D. Repeated short blasts of the air horn for approximately ten seconds, followed by ten seconds of silence, three times.

Answer: (D)

The key idea is a clearly defined, attention-getting evacuation cadence. The standard signal uses short air horn blasts for about ten seconds, then ten seconds of silence, and this sequence is repeated three times. This repeating pattern creates a unmistakable alarm that crews can recognize and respond to quickly even in noisy, high-stress conditions, ensuring everyone evacuates promptly to safety. The other patterns don’t establish the same reliable cadence or repetition, so they aren’t used as the official evacuation signal by RVC and CAL/Fire.