What is the minimum decibel level for a fire alarm signal?

What is the minimum decibel level for a fire alarm signal?

• A. 70db
• B. 80db
• C. 90db
• D. 75db

Answer: (D)

Audible notification signals in a fire alarm system are designed to be clearly heard above typical room noise, so the standard sets a minimum level at the occupant’s ear. Not less than 75 dBA (A-weighted) at the most remote or critical occupancy location ensures people can hear the alarm without it being excessive in calmer areas. In spaces with unusually high background noise, designers may raise levels or add other cues like strobes or voice evacuation, but the required minimum is 75 dBA. That's why the correct choice is 75 dB.

Audible notification signals in a fire alarm system are designed to be clearly heard above typical room noise, so the standard sets a minimum level at the occupant’s ear. Not less than 75 dBA (A-weighted) at the most remote or critical occupancy location ensures people can hear the alarm without it being excessive in calmer areas. In spaces with unusually high background noise, designers may raise levels or add other cues like strobes or voice evacuation, but the required minimum is 75 dBA. That's why the correct choice is 75 dB.