Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 80·6.5 note 3
Flue termination distance from oil storage tanks
Flue termination points must be at least 1800 mm from oil storage tanks unless a fire wall is provided between them.
The terminating point of any flue should be not less than 1800 mm from an oil storage tank unless a fire wall as described in (b) above is provided between the tank and the flue termination.
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