(1)
Except as permitted by Sentence (2) and Articles 3.1.5.22. and 3.1.5.25., optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes are permitted in a building required to be of noncombustible construction, provided
(a)
the wires and cables exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test – Cables in Cable Trays (FT4 rating) in CSA C22.2 No. 0.3, “Test methods for electrical wires and cables,”
(b)
the wires and cables are located in
(i)
totally enclosed noncombustible raceways, (See Note A-3.1.4.3.(1)(b)(i))
(ii)
masonry walls,
(iii)
concrete slabs,
(iv)
a service room separated from the remainder of the building by a fire separation having a fire-resistance rating not less than 1 h, or
(v)
totally enclosed non-metallic raceways conforming to Clause 3.1.5.23.(1)(b), or
(c)
the wires and cables are communication cables used at the service entry to a building and are not more than 3 m long. (See Note A-3.1.5.21.(1))
(2)
Except as permitted in Sentences (3) and (4), optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes that are used for the transmission of voice, sound or data and are not located in totally enclosed noncombustible raceways are permitted to be installed in a plenum in a building required to be of noncombustible construction, provided the wires and cables exhibit a horizontal flame distance of not more than 1.5 m, an average optical smoke density of not more than 0.15, and a peak optical smoke density of not more than 0.5 when tested in conformance with CAN/ULC-S102.4, “Standard Method of Test for Fire and Smoke Characteristics of Electrical Wiring, Cables and Non-Metallic Raceways,” (FT6 rating).
(3)
Except as permitted in Sentence (4), where totally enclosed noncombustible raceways are used in a plenum, exposed components of wiring systems with combustible insulation, jackets or sheathes, including optical fibre cables and electrical wires and cables that are used for the transmission of voice, sound or data, that are installed in the plenum or that extend not more than 9 m from the plenum including drop down to the floor level, are permitted provided they exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test – Cables in Cable Trays (FT4 rating) in CSA C22.2 No. 0.3, “Test methods for electrical wires and cables.”
(4)
Cables or wires within plenums that are used for the transmission of signals in fire alarm systems need not comply with the requirements of Sentences (2) and (3).