The Ontario Building Code | Enclosure Exhaust Ventilation
220.127.116.11. Enclosure Exhaust ventilation
(a) conform to nfpa 91, "Exhaust Systems for Air Conveying of Vapors, Gases, Mists and Noncombustible Particulate Solids",
(c) confine flammable vapours and particles to the area where they are generated and exhaust them to the outdoorref ="http://thehandyforce.com/doors/" title ="Toronto Door installer">doors,
(d) not return the exhausted air to the building, and
(e) be provided with well identified control switches that are,
(i) located outside the power-ventilated enclosure, and
(ii) readily accessible in case of an emergency.