(1) Except as provided in Sentences (2) and (3), outlet boxes are permitted to penetrate the membrane of an assembly required to have a fire-resistance rating, provided they are sealed at the penetration by a fire stop 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, “Fire Tests of Firestop Systems”.
(2) Except as provided in Sentences 3.1.9.1. (2) and (3), noncombustible outlet boxes that penetrate a vertical fire separation or a membrane forming part of an assembly required to have a fire-resistance rating need not conform to Sentence (1), provided,
(a) they do not exceed,
(i) 160 cm² in area, and
(ii) an aggregate area of 650 cm² in any 9.3 m² of surface area, and
(b) the annular space between the membrane and noncombustible electrical outlet boxes does not exceed 3 mm.
(3) In addition to the requirements of Sentence (2), outlet boxes on opposite sides of a vertical fire separation having a fire-resistance rating shall be separated by,
(a) a horizontal distance of not less than 600 mm, or
(b) a fire block conforming to Article 3.1.11.7.