(1)

Fire stop flaps in ceiling membranes required in Sentence 9.10.5.1.(3) shall

(a)

conform to CAN/ULC-S112.2, “Standard Method of Fire Test of Ceiling Firestop Flap Assemblies,” and

(b)

activate at a temperature approximately 30°C above the normal maximum temperature that occurs in the ducts, whether the air duct system is operating or shut down.