The Ontario Building Code | Walls in Exits

9.10.17.3. walls in Exits

(1) Except as provided in Sentence (2), at least 90% of the exposed surfaces of every wall in an exit shall have a surface flame-spread rating of not more than 25.

(2) At least 75% of the wall surface of a lobby used as an exitin Article 9.9.8.5. shall have a surface flame-spread rating of not more than 25.