Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 67·4.36
Shielding of gas-fired appliances
Gas-fired appliances must be located to prevent accidental contact and surrounded by non-combustible surfaces with adequate separation from combustible materials, either through a 25 mm non-combustible shield or a 75 mm air space.
A gas-fired appliance should be located where accidental contact is unlikely and it should be surrounded by a non-combustible surface which provides adequate separation from combustible materials. The appliance should be installed –
(a) with a shield of non-combustible material with a minimum thickness of 25 mm, between the appliance and the combustible material. See Diagram 4.8; or
(b) with an air space of not less than 75 mm between the appliance and the combustible material. See Diagram 4.8.
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