3.1.5.16.

(1) Except as permitted by Clause 3.1.5.2.(1)(d) , Sentences (2) and (3), and Article 3.1.5.22., 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.v1, 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.

(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,

(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 fire stop system that, when subjected to the fire test method in CAN4-S115-M, “Fire Tests of Firestop Systems”, has an FT rating not less than the fire-resistance rating of the fire separation.