Fire Alarm

[LeviDixon]

Does anyone know where in the NEC is the topic of decibel levels discussed? Ive looked all over the book but have had no luck. I think that it is 85db but need to see it in a code book to be satisfied.

Can anyone give me an article and section number?

 

[david]

Not sure you may want to look in NFPA 72

 

[Hv&Lv]

You looking for the audible characteristics? Look at NPFA 72 4-3.1

 

[WorkSafe]

NFPA 72

18.4.3.1* To ensure that audible public mode signals are clearly heard, unless otherwise permitted by 18.4.3.2 through 18.4.3.5, they shall have a sound level at least 15 dB above the average ambient sound level or 5 dB above the maximum sound level having a duration of at least 60 seconds, whichever is greater, measured 5 ft (1.5 m) above the floor in the area required to be served by the system using the A-weighted scale (dBA).

 

[LeviDixon]

Thank you for the responses. Does the NFPA read anything along the lines of 85db?

 

[ron]

Thank you for the responses. Does the NFPA read anything along the lines of 85db?

It does not indicate an absolute, it is 15dB above ambient as shown by Worksafe's quote from 72. There is an absolute max, but no min, unless it is really quiet, then the min could be 15 ......

 

[kwired]

Thank you for the responses. Does the NFPA read anything along the lines of 85db?

It does not indicate an absolute, it is 15dB above ambient as shown by Worksafe's quote from 72. There is an absolute max, but no min, unless it is really quiet, then the min could be 15 ......

That only makes sense. If ambient was already 85 what good would an alarm of 85 be?