Appendix B Rule 2-130
The flame spread requirements for insulated conductors and cables installed with exposed outer combustible insulation or jackets in buildings are located in the National Building Code of Canada as follows:
a) combustible building construction — Article 3.1.4.3 and Article 9.34.1.5;
b) non-combustible building construction — Article 3.1.5.21; and
c) plenum spaces in buildings — Article 3.6.4.3.
The markings for conductors and cables meeting the flame spread requirements of the National Building Code of Canada (i.e., for conductors and cables installed with exposed outer combustible insulation or jackets) are
a) FT1* — insulated conductors and cables that are suitable for installation in buildings of combustible construction;
b) FT4† — insulated conductors and cables that are suitable for installation in buildings of non combustible and combustible construction; and
c) FT6‡ — insulated conductors and cables that are suitable for installation in
i) buildings of non-combustible and combustible construction; and
ii) spaces between a ceiling and floor, or ceiling and roof, that may be used as a plenum in buildings of combustible or non-combustible construction.
* Communication and optical fiber cables marked CMP, CMR, CMG, CM, CMX, CMH, OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, OFC, OFNH, OFCH, and communication and optical fiber cables marked FT4 have been found to meet the standard criteria for FT1.
† Communication and optical fiber cables marked CMP, CMR, CMG, OFNP, OFCP, OFNR, OFCR, OFNG, and OFCG have been found to meet the standard criteria for FT4.
‡ Communication and optical fiber cables marked CMP, OFNP, and OFCP have been found to meet the standard criteria for FT6.
Armoured cables without exposed outer combustible jackets may be considered to comply with the National Building Code of Canada requirements relating to flame spread. Insulated conductors and cables with exposed outer combustible insulation or jackets that do not meet the above classifications but that are installed in
a) totally enclosed non-combustible raceways;
b) masonry walls;
c) concrete slabs;
d) a service room separated from the remainder of the building by a fire separation having not less than 1 h fire-resistance rating; or
e) totally enclosed non-metallic raceways conforming to Rule 2-132 may be considered to comply with the National Building Code of Canada requirements relating to flame spread.
It is the intent of this Rule to limit flame spread and smoke propagation of cables in plenum spaces to the values specified by Article 3.6.4.3 (1) (a) of the National Building Code of Canada. Authorities enforcing provisions of the National Building Code of Canada and the National Fire Code of Canada in each jurisdiction should be consulted in order to determine the acceptable volume of cables in plenums for the purpose of conformance with the National Building Code of Canada and the National Fire Code of Canada requirements.
Sentence 2.4.1.1 (5) of the National Fire Code of Canada (2015 edition) requires that, when located in plenum chambers, abandoned optical fiber cables and electrical cables with combustible insulation, jackets, or sheaths be removed except when
a) the cables or raceways are permanently enclosed by the structure or finish, such as inside a wall located in a plenum;
b) the cables or raceways are not capable of being removed without disturbing the building structure or finish, such as when embedded in plaster, cement, or similar finish; or
c) there is a risk that the removal of the cables or raceways will affect the performance of cables in use.
For example, if abandoned cables are located in a cable tray together with cables in use and their removal could adversely affect the safety or performance of the cables in use, then the abandoned cables can be left in place.
Source: Appendix B Rule 2-130, 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
