Covers design and construction of flue linings and flue structures serving appliances of 45 kW output and above, burning solid, liquid or gaseous fuels. Applies to flue structures within a space enclosed by a building or which are an integral part of the building.Cross References:BS 784BS 835BS 1449:Part 2BS 1470BS 1758BS 2869BS 4076BS 4207CP 3:Chapter V:Part 1CP 3:Chapter V:Part 2CP 111:Part 2CP 326