The Ontario Building Code | Wires and Cables
3.1.4.3. wires and Cables
(1) Except as permitted by Sentences (2) and (3), optical fibre cables and electrical wires and cables with combustibleinsulationhttp://thehandyforce.com/insulation/" title ="Toronto home insulation">insulation, jackets or sheathes installed in a buildingpermitted to be of combustible construction shall,
(a) not convey flame or continue to burn for more than 1 min when tested in conformance with the Vertical Flame Test in Clause 4.11.1. of CSA C22.2 No. 0.3, "Test Methods for Electrical wires and Cables" (FT1 Rating), or
(b) be located in,
(i) totally enclosed noncombustible raceways,
(ii) concealed spaces in walls,
(iii) concrete slabs, or
(iv) totally enclosed nonmetallic raceways conforming to Clause 3.1.5.20(1)(b).
(2) The requirement in Clause (1)(a) is considered to be met where the wires and cables,
(a) exhibit a vertical char of not more than 1.5 m when tested in conformance with the Vertical Flame Test – Cables in Cabletrough in Clause 4.11.4. of CSA C22.2 No. 0.3, "Test Methods for Electrical wires and Cables" (FT4 Rating), or
(b) exhibit a flame-spread of not more than 1.5 m, a smoke density of not more than 0.5 at peak optical density and a smoke density not more than 0.15 at average optical density when tested in conformance with the Flame and Smoke Test in the Appendix to CSA C22.2 No. 0.3, "Test Methods for Electrical wires and Cables" (FT6 Rating).
(3) service-entrance cables for communication and community antennae distribution systems need not conform to Sentence (1) provided,
(a) the service-entrance cables are located in a building permitted to be of combustible construction and are not more than 3 m in length from the point of entry into the building or from the point of leaving protection as required in Clause (1)(b), or
(b) the service-entrance cables enter into an electrical or telephone service roomseparated from the remainder of the building by a fire separation having a fire-resistance rating not less than 1 h.