June 27, 1984
BCAB #753
Re: Termination of Kitchen Exhaust Ducts, NFPA 96
With reference to your letter of February 7, 1984, regarding the rooftop termination of an exhaust duct serving commercial cooking equipment.
The matter is covered by Section 3.3 of NFPA 96-1978 "Vapour Removal of Cooking Equipment". This sets out clearances to provide safety in the vent of duct originating fires, and also to prevent fumes re-entering the building.
For the purposes of this particular situation we consider that 3-3.1, 3.2, and 3.3 all have application. With respect to clearance from the roof surface we would consider a duct acceptable in a depressed well, provided that the installation also met the provisions of 3-3.1. For this circumstance we would regard the ten foot clearance as applicable to an adjacent section of the same building.
While we appreciate that the duct system in question is provided with automatic washdown and other safety features, we are unable to accept that this permits relaxation of Section 3-3.
From the information submitted we must conclude that the installation does not conform with the required standard.
J.C. Currie, Chair