Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 33·2.42
Openings in flues for inspection and cleaning
Flues should not open into more than one room or space except when necessary for inspection, cleaning, or fitting devices such as explosion doors, draught breaks, draught stabilisers or draught diverters.
A flue should not have an opening into more than one room or space except for the purposes of – (a) inspection or cleaning; or (b) fitting an explosion door, draught break, draught stabiliser or draught diverter.
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