BS EN 12285-1:2003 specifies the requirements for shop fabricated cylindrical, horizontal steel tanks, single and double skin for the underground storage of water polluting liquids (both flammable and non-flammable) within the following limits:
- from 800 mm up to 3 000 mm nominal diameter
- up to a maximum overall length of 6 times the nominal diameter
- for liquids with a maximum density of up to 1,9 kg/l and with an operating pressure of maximum 1,5 bar (abs.)
- for double skin tanks with a vacuum leak detection system where the kinematic viscosity does not exceed 5 x 10-3 m2/s.
This standard is applicable for normal operating temperature conditions (-20 degrees C to +50 degrees C). Where temperatures are outside of this range, additional requirements should be taken into account.