UL 51 PDF

1.1 These requirements cover power-operated pumps for anhydrous ammonia and liquefied petroleum gas (LP-Gas) for use in liquid transfer operations in nonrefrigerated systems in installations covered by the:

Safety Requirements for the Storage and Handling of Anhydrous Ammonia, CGA/GAS K61.1 and Standard for Liquefied Petroleum Gas Code, NFPA No. 58.

1.2 These requirements do not cover:

Pumps or compressors intended for handling anhydrous ammonia or LP-Gas in the gaseous phase and Pumps or compressors for anhydrous ammonia or LP-Gas for use in chemical, petro-chemical, petroleum, or utility power plants; nor pipeline or marine terminals; nor related storage facilities at such plants or terminals.

1.3 A pump complying with these requirements is intended for use in applications where the vapor pressure of the liquid handled is not more than 200 pounds per square inch gauge (psig) (1380 kPa) at 37.8° C (100° F) and the maximum discharge pressure in the pumping system does not exceed 350 psig (2415 kPa).