Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 37·3.1
Air supply to appliances
Rooms or spaces containing combustion appliances must have permanent air vent openings sized according to Table 3.1, with consideration for the fuel type that produces the highest heating output.
Any room or space containing a combustion appliance should have a permanent air vent opening of a size not less than that shown in Table 3.1. For an appliance designed to burn a range of different solid fuels, the air supply should be designed to accommodate burning the fuel that produces the highest heating output.
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