Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 45·3.20
Lining or relining flues in chimneys
Flue linings must meet the designation T400 N2 D3 G as specified in BS EN 1443 standard.
The lining of a flue should correspond to the designation T400 N2 D3 G, as described in BS EN 1443.
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