Above Ground Flammable/Combustible Liquids

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1 . G SFMD Fact Sheet INS-FACT 1999-11 November 1, 1999 Page 3 of 4 Additional requirements for UL 142 AST UL 142 above ground storage tanks are plain steel tanks that may be either single or double wall. These tanks are not constructed to be fire resistive and thus have requirements for separation between the tank and buildings and also between the tank and dispenser. This page covers the additional requirements for single and double wall plain steel UL 142 tanks.Note the separation required between the tank and buildings plus the separation required between tank and dispenser. 1. A maximum of three ASTs are allowed for dispensing at any single dispensing site.AST shall no; exceed 6,000 gallons individual capacity for Class I liquids (gasoline)and 10,000 gallons individual capacity for Class H liquids (diesel fuel). 2. ASTs shall be separated from the dispenser by at least 30 feet. Exceptions: 1. Operations not open to the public and for resort operations serving re?istered ?uests oniv. dispensing of Class I liquids from one AST of 560 gallons capacity or less may have the dispenser located on top of. or adjacent to, the AST. 2. Operations not open to the public and for resort operations serving registered Quests oniv, Cwo AST of 1,000 gallons individual canacity or less may dispensing of Class II liquids from have the dispenser located on too of. or adiacent to. the AST. 3. Tanks shall be located not less than 50 feet from the nearest side of a public way, property line, building, or combustible storage located on the same property. Exception: ASTs which are separated by 30 feet or more from the dispenser may reduce the distances between the AST and the public way, property line, building, or combustible storaQe to 30 feet. !. Fuel delivery shall be -om the top or the AST with the dispensing line equipped with an approved antisyphon system. 6. Dispensing lines between a diked area or_-\.ST and a dispenser shall be Tocated underground and shall be in an approved secondary containment piping system. 6. Dispensing lines shall have an approved normally closed solenoid valve at each dispenser below the impact valve. 7. Fill pipes between a diked area or AST and the fill pipe opening shall be located underground. The fill pipe shall also be equipped with manually operated mechanical shut-off valve located inside the diked area, but can be operated from outside the dike. 3. ASTs shall be provided with lightning protection in accordance with the National Fire Protection Association Standard 780 (1994 edition). 9. When required by the local fire chief,multiple AST installations shall be protected by an approved fire protection system.