Re: NFPA Code Question

["Michael Baker" <mbbaker@xxxxxxxxx>]

Nomen Nescio wrote:
> Mike Baker said:
>
> >See NFPA 72 Chapter 11.3.2 and A.11.3.2.
> >
> >Where the building code requires smoke detection in a one or two family
> >dwelling, one of the following two methods are allowed:
> >
> >1) Self-contained smoke alarm(s) installed in sleeping rooms and
> >outside sleeping rooms and on each additional level within the dwelling
> >or;
> >
> >2) A system of smoke detector(s) installed in sleeping rooms and
> >outside sleeping rooms and on each additional level within the
> >dwelling.
> >
> >Item number 2 requires a control panel, which in turn requires a smoke
> >detector to supervise the its location.
>
> I disagree.  You're citing section 4.4.5, which, I think, is the only NFPA
> 72 requirement concerning panel protection using a smoke detector.
> However, section 4.1.2 says:
>
> "The requirements of this chapter shall apply to fire alarm systems,
> equipment, and components addressed in Chapter 5 through Chapter 10."
>
> Household fire alarm systems are covered by Chapter 11.  Your requirement
> doesn't apply.  If it did, what other Chapter 4 requirements should also
> apply?  All of them?

Admittedly, the thread supporting my statement is disjointed.
Nonetheless, the thread exists (at least in my tiny little brain).

> I understand your point of view:  if a system uses smoke alarms, they will
> not all be disabled by a single fire, but if a system depends on a single
> control panel, a single fire at the control panel could wipe out the entire
> system.  Probably this is something that should be addressed during the
> next code development cycle.

The requirement to install a smoke detector to "protect" control
equipment was initially removed in the 2007 code cycle.  At the last
minute the requirement was reinstated with the intent to eventually
remove it once the requirement is added to the IBC/IFC.  Likewise for
the single manual box requirement.

> Personally, I think it's a bit wasteful to put a smoke detector inside a
> small residential closet.  I think 4.4.5, and any future Chapter 11
> section, should permit the use of a rate of rise detector instead of a
> smoke detector, under all conditions.  So far as I know, no fire alarm
> control panel has ever been disabled by smoke. :-)

I know, it sounds silly, however, Annex A indicates that anecdotal
evidence supports the requirement.  Smoke detection vs. heat detection
to ensure action is taken before the control is incapacitated by fire.
While the rule requires a smoke detector, the exception allows a heat
detector to be used.

> - badenov

Mike