Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 25·2.17(a)
Extract fan rate limits for gas appliances with open-flued combustion
For rooms containing open-flued gas appliances, extract fan rate must not exceed 20 litres/second (72 m³/hour), and a spillage test to BS 5440: 1 should be carried out.
for a gas appliance – where a room contains an open-flued appliance, the room extract fan rate should not exceed 20 litres/second (72 m3/hour), and a spillage test as recommended in BS 5440: 1 should be carried out.
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