Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 15
Definitions: Chimney, Combustion Appliance, and Designation
Definitions of key terms used in the technical booklet: chimney as an enclosing structure for flues; combustion appliance as defined in Building Regulations Part L; and designation as the performance code for flues per BS EN 1443.
Chimney – a structure consisting of a wall or walls enclosing one or more flues. See Diagram 1.1.
Combustion appliance – has the meaning assigned to it by regulation 69 in Part L of the Building Regulations.
Designation – BS EN 1443 expresses the performance characteristics of a flue or its components, as assessed in accordance with an appropriate European product standard, by means of a code such as "EN 1234 T400 P1 S W 1 R22 C50". This code is known as the designation for the flue or its components. See Appendix B.
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