The Ontario Building Code | Basements
3.3.5.3. basements
(1) A basement shall not be used for the storage, manufacture or handling of volatile solids, liquids or gases that generate explosive air-vapour mixtures or for processes that involve explosive dusts.
(2) Entrances and exits to a basement and to rooms containing buildingservices shall be separate from the remainder of the buildingin a building in which,
(a) the storage, manufacture or handling of volatile materials can generate explosive air-vapour mixtures, or
(b) processes occur that produce explosive dusts.
(3) Basements and rooms referred to in Sentence (2) shall be separated from the remainder of the building with a vapour-tight separation.