3.1.5.19.Combustible Piping Materials

(1) Except as permitted by Clause 3.1.5.2.(1)(d) and Article 3.1.5.25. and Sentences (2) and (3), combustible piping and tubing and associated adhesives are permitted to be used in a building required to be of noncombustible construction provided that, except when concealed in a wall or concrete floor slab, they (a) have a flame-spread rating not more than 25, and (b) if used in a building described in Subsection 3.2.6., have a smoke developed classification not more than 50. (2) Combustible sprinkler piping is permitted to be used within a sprinklered floor area in a building required to be of noncombustible construction. (See also Article 3.2.5.13.) (3) Polypropylene pipes and fittings are permitted to be used for drain, waste and vent piping for the conveyance of highly corrosive materials and for piping used to distribute distilled or dialyzed water in laboratory and hospital facilities in a building required to be of noncombustible construction, provided (a) the building is sprinklered throughout, (b) the piping is not located in a vertical shaft, and (c) piping that penetrates a fire separation is sealed at the penetration by a firestop that has an FT rating not less than the fire-resistance rating of the fire separation when subjected to the fire test method in CAN/ULC-S115, “Standard Method of Fire Tests of Firestop Systems,” with a pressure differential of 50 Pa between the exposed and unexposed sides, with the higher pressure on the exposed side.