Code Library › Volume 1 › Section 3.3 — Safety Within Floor Areas (See Note A-3.3.)
PART 3 — FIRE PROTECTION, OCCUPANT SAFETY AND ACCESSIBILITYUpdated for the 2024 Ontario Building Code

3.3.1.21.Exhaust Ventilation and Explosion Venting

(1) Except as provided in Sentence (2), an exhaust ventilation system designed in conformance with the appropriate requirements of Part 6 shall be provided in a building or part of a building in which dust, fumes, gases, vapour or other impurities or contaminants have the potential to create a fire or explosion hazard. (See also Article 4.2.4.13.) (2) Where a fire separation required to have a fire-resistance rating is penetrated by a ventilation system required by Sentence (1) for power-ventilated enclosures in laboratories, the ducts shall be (a) continuously enclosed from the first penetrated fire separation to any subsequent fire separations or concealed spaces and all the way through to the outdoors so that the highest fire-resistance rating of all the penetrated fire separations is maintained, and (b) exempted from the requirement to be equipped with a fire damper, smoke damper and combination smoke/fire damper as stated in Article 3.1.8.7. (3) Explosion relief devices, vents or other protective measures conforming to Subsection 6.3.1. and Article 6.9.1.2. shall be provided for a space in which substances or conditions that have the potential to create an explosion hazard are present as a result of the principal use of a building.
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Code text is reproduced for reference from the Ontario Building Code (O. Reg. 163/24, 2024 Building Code Compendium). This page is provided for general information and is not an official copy. Always verify requirements against the official Ontario Building Code and confirm with your local building department.