Appendix B Rules 2-132 and 12-1602
The flame spread requirement for totally enclosed non-metallic raceways can be found in Article 3.1.5.23 of the National Building Code of Canada. The National Building Code of Canada permits the use of totally enclosed non-metallic raceways for insulated conductors and cables in buildings required to be of non combustible construction, provided that the totally enclosed non-metallic raceways do not exceed 175 mm in outside diameter, or equivalent cross-sectional area, and conform to the vertical flame test requirement specified in Clause 6.16 of CSA C22.2 No. 211.0.
The marking on totally enclosed non-metallic raceways to indicate compliance with this flame test is “FT4”.
The National Building Code of Canada also permits the use of totally enclosed non-metallic raceways in plenums of buildings. Where a totally enclosed non-metallic raceway is installed in a plenum of a building permitted to be of combustible construction, such a raceway should meet, as a minimum, the requirements of an FT4 rating. Where a totally enclosed non-metallic raceway is installed in a plenum of a building required to be of non-combustible construction, such a raceway should meet the requirements of an FT6 rating.
Source: Appendix B Rule 2-132, CSA C22.1:21, Canadian Electrical Code, Part 1 (25th Edition), Safety Standard for Electrical Installations. © 2021 Canadian Standards Association. Please visit store.csagroup.org
