CAN3-B255-M81 (R2012)

1. Scope 1.1 This Standard applies to mechanical flue-gas exhausters intended to be installed in a flue pipe, breeching, or chimney and serving appliances burning natural gas, propane, or fuel oil. 1.2 This Standard covers the mechanical and electrical features of mechanical flue-gas exhausters for indoor or outdoor installations. 1.3 This Standard classifies mechanical flue-gas exhausters as Type 1, 2, or 3 suitable for maximum operating temperatures of 300°C (575°F), 550°C (1000°F), or 850°C (1600°F), respectively. 1.4 This Standard is not intended to cover mechanical flue-gas exhausters with motor ratings exceeding 375 W (1/2 hp). 1.5 This Standard is not intended to cover mechanical flue-gas exhausters for use with incinerators, incinerating toilets, or condensing type or solid fuel burning appliances. 1.6 This Standard may also be applied to such equipment as air circulators and boosters. 1.7 Metric units of measurement in this Standard are in accordance with the International System of Units (SI). If a value for measurement as given in this Standard is followed by an equivalent value in other units, the first stated is to be regarded as the requirement. A given equivalent value may be approximate.