The storage of flammable liquids in tanks (HSG176) (link)
This second edition of HSG176 applies to above and below ground fixed bulk storage tanks. It applies to premises where flammable liquids are stored in individual tanks or groups of tanks. It may also be applied to portable or skid-mounted vessels with capacities in excess of 1000 litres.
It also gives guidance on the design, construction, operation and maintenance of installation used for the storage of flammable liquids in fixed and transportable tanks operating at or near atmospheric pressure.
Source: HSE