DS EN 12285-1:2003 Workshop Fabricated Steel Tanks - Part 1: Horizontal Cylindrical Single Skin And Double Skin Tanks For The Underground Storage Of Flammable And Non-Flammable Water Polluting Liquids Defines 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).