The Ontario Building Code | Fire Dampers
18.104.22.168. Fire Dampers
(1) Except as permitted in Sentences (2) to (5) and Sentence 22.214.171.124.(4), a duct that penetrates an assembly required to be a fire separationwith a fire-resistance rating shall be equipped with a fire damper in conformance with Articles 126.96.36.199. and 188.8.131.52.
(2) Afire damper is not required where a noncombustible branch duct pierces a required fire separation provided the duct,
(a) has a melting point not below 760°C,
(b) has a cross-sectional area less than 130 cm², and
(c) supplies only air-conditioning units or combined air-conditioningand heating units discharging air at not more than 1.2 m above the floor.
(3) Afire damper is not required where a noncombustible branch duct pierces a required fire separation around an exhaust duct riser in which the air flow is upward provided,
(a) the melting point of the branch duct is not below 760°C,
(b) the branch duct is carried up inside the riser at least 500 mm, and
(c) the exhaust duct is under negative pressure as described in Article 184.108.40.206.
(4) Noncombustible ducts that penetrate a fire separation separating a vertical service space from the remainder of the buildingneed not be equipped with a fire damper at the fire separation provided,
(a) the ducts have a melting point above 760°C, and
(b) each individual duct exhausts directly to the outside at the top of the vertical service space.
(5) A duct serving commercial cooking equipment and piercing a required fire separation need not be equipped with a fire damper at the fire separation.