UL 125

Flow Control Valves for Anhydrous Ammonia and LP-Gas

UL 125

1 Scope

1.1 These requirements cover the following types of anhydrous ammonia and liquefied petroleum gas (LP-Gas) valves that are used to control the flow of liquid and/or vapor into and out of containers, or in piping systems between containers, or between containers and utilization equipment, and are for use at temperatures within the range of minus 40°F (minus 40°C) to 130°F (55°C):

• Shut-off Valves (primary or secondary, and manual or automatic),
• Excess Flow Valves,
• Back Pressure Check Valves,
• Filler Valves,
• Vapor Return Valves,
• Actuated Liquid Withdrawal Excess-Flow Valves;
• Multiple function valves;
• Internal valve;
• Emergency shutoff valve; and
• Lever operated transfer valve.

1.2 Valves covered by these requirements are for use in systems and facilities covered in the following Standards:

• Safety Requirements for the Storage and Handling of Anhydrous Ammonia, ANSI/CGA G-2.1 ( ANSI K61.1);
• Liquefied Petroleum Gas Code, NFPA 58; and
• Utility LP-Gas Plant Code, NFPA 59.

1.3 These requirements do not cover shut-off valves of the type commonly referred to as “cylinder valves” used on containers constructed under Department of Transportation (DOT) Specifications. Requirements for these valves are contained in the Standard for Cylinder Valves, UL 1769.

1.4 These requirements do not cover safety relief valves. Requirements for these valves are contained in the Standard for Safety Relief Valves for Anhydrous Ammonia and LP Gas, UL 132.

1.5 These requirements do not cover automatic shutoff valves that use electricity to actuate the valve member. Requirements for these valves are contained in the Standard for Electrically Operated Valves, UL 429.

1.6 These requirements do not apply to LP-Gas valves for use on containers or in systems for the following:

• Refrigerated storage systems and
• Marine and pipeline terminals, chemical plants, natural gas processing plants, refineries or tank farms, where “tank farms” do not include storage at industrial locations.

1.7 These requirements do not apply to valves for anhydrous ammonia for use on containers or in systems for the following:

• Refrigerated storage systems,
• Ammonia manufacturing plants,
• Refrigeration plants where ammonia is used solely as a refrigerant, and
• Ammonia transportation pipelines.

1.8 Except for such observations as are required to ascertain performance characteristics, the assigning of flow capacity ratings, other than for excess flow valves, is not within the scope of these requirements.