3.1.5.21.

(1) Optical fibre cables and electrical wires and cables with combustible insulation, jackets or sheathes, located in the space below a raised floor in a computer room, are permitted in a building required to be of noncombustible construction provided they do 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).

(2) The requirement in Sentence (1) 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).