Interpretation #6684

Original Request

Code Version: 2007
Code: BUILDING
Code Description: Building
Chapter: 7
Section: 710.5.2 and 716.5.4.1
Topic: Fire Rating of elevator machine rooms

Question

I have two questions. First question: Is it the intent of FBCB 710.5.2 to require smoke and draft control doors in exit access corridors in a fully sprinklered public education facility? The second question: Is it the intent of FBCB 716.5.4.1 to require smoke dampers for all air ducts penetrating an exit access corridor enclosure when using a standard [non- fire /smoke rated] acoustical tile suspended ceiling grid system instead of walls extending to the underside of the roof /floor assembly above?

Answer Published 12/06/2011 at 12:55 PM

Question 1: Section 710.5.2 does not address where smoke
and draft control doors are required. You must go to
715.4.3 to determine if smoke and draft control doors are
required in the corridor. Essentially, if the corridor is
required to be fire resistance rated, then smoke and draft
control doors are also required.
Question 2: 716.5.4.1 only requires smoke dampers in duct
penetrations of corridors if smoke and draft control
doors are required by 715.4.3. Again, this would mean only
if the corridor walls are required to be fire resistance
rated.

Commentary

Comment 2: This is a building official’s call. In a smoke partition, smoke dampers are only required in air transfer openings, not at duct penetrations, per 710.7. The duct penetration need only be sealed (filled) with an approved material to limit the free passage of smoke.