Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 49·3.26
Hearth location and non-combustible surface requirement
Combustion appliances must be located on a hearth surrounded by a non-combustible surface, with edges marked by a change in level to warn occupants and prevent combustible floor finishes from being laid too close.
An appliance should be located on a hearth so that it is surrounded by a surface free of combustible material as shown in Diagram 3.9. This surface may be part of the surface of the constructional hearth or it may be the surface of a superimposed hearth laid wholly or partly upon a constructional hearth. The edges of this surface should be marked with a change in level to provide a warning to the building occupants and to discourage combustible floor finishes such as carpet from being laid too close to the appliance.
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