Combustion heater fire protection.

CFR · 2024-01-01 · US · Title 14

(a) (1) The region surrounding the heater, if this region contains any flammable fluid system components (excluding the heater fuel system), that could— (i) Be damaged by heater malfunctioning; or (ii) Allow flammable fluids or vapors to reach the heater in case of leakage. (2) The region surrounding the heater, if the heater fuel system has fittings that, if they leaked, would allow fuel or vapors to enter this region. (3) The part of the ventilating air passage that surrounds the combustion chamber. However, no fire extinguishment is required in cabin ventilating air passages. (b) (1) Unless isolation is provided by fireproof valves or by equally effective means, the ventilating air duct downstream of each heater must be fireproof for a distance great enough to ensure that any fire originating in the heater can be contained in the duct; and (2) Each part of any ventilating duct passing through any region having a flammable fluid system must be constructed or isolated from that system so that the malfunctioning of any component of that system cannot introduce flammable fluids or vapors into the ventilating airstream. (c) (1) No combustion air duct may have a common opening with the ventilating airstream unless flames from backfires or reverse burning cannot enter the ventilating airstream under any operating condition, including reverse flow or malfunctioning of the heater or its associated components; and (2) No combustion air duct may restrict the prompt relief of any back

official document · source cfr-2024 · id 14:§ 25.859