907.5.2.1.1 Average sound pressure.
BC § 907.5.2.1.1
The audible alarm notification appliances shall provide a sound pressure level of 15 decibels (dBA) above the average ambient sound level or 5 dBA above the maximum sound level having a duration of not less than 60 seconds, whichever is greater, in every occupiable space within the building. The minimum sound pressure levels shall be: 75 dBA in occupancies in Groups R and I-1; 90 dBA in mechanical equipment rooms and 60 dBA in other occupancies. For one-way voice communication system in Group R-2 occupancies, the minimum sound pressure level of the alert tone shall be 75 dBA throughout the dwelling unit.













