Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 10·77
Prevention of smoke emission
Combustion appliances for heating or cooking that discharge to external air must be capable of or readily adaptable to smokeless fuel burning, unless they are a compliant furnace or an exempted appliance class.
A combustion appliance installed in a building for the purpose of heating or cooking, and which discharges its combustion products to the external air shall be capable of, or readily adaptable to, the burning of fuel smokelessly, unless it is—
(a) a furnace which complies with Article 5 of the Clean Air (Northern Ireland) Order 1981 (which requires that new furnaces shall so far as practicable be smokeless); or
(b) an appliance of a class exempted conditionally or unconditionally from the provisions of Article 17 of the Clean Air (Northern Ireland) Order 1981 (which relates to smoke control areas) by any order for the time being in force under paragraph (7) of that Article.
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