The Ontario Building Code | Exhaust Ducts Serving More Than One Fire Compartment
9.10.9.18. Exhaust Ducts Serving More Than One Fire Compartment
(1) Where a vertical service space contains an exhaust duct that serves more than one fire compartment, the duct shall have a fan located at or near the exhaust outlet to ensure that the duct is under negative pressure.
(2) Individualfire compartments referred to in Sentence (1) shall not have fans that exhaust directly into the duct in the vertical service space.
In Plain Language
Exhaust ducts serving more than one fire compartment must meet the requirements set out in this article, since a shared duct could otherwise let fire or smoke bypass a fire separation.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.