July 20, 2006



July 20, 2006

SUMMARY OF REQUIREMENTS

The following is a brief summary of the new and revised paragraphs in the Standard for Cylinder Valves, UL 1769, which have a future Effective Date of June 30, 2008 and the action that may be required to determine compliance.

|Paragraphs |General Subject and Comment |

|5.7 |A valve for LP-Gas for use on nominal 4 – 40 pound nominal LP-Gas capacity (10.2 – 95.3 pound water capacity) shall be provided with all |

| |of the following: |

| | |

| |c) A fixed maximum liquid level gauge including a dip tube. The vent valve portion of the gauge shall be of the type that incorporates a |

| |flat-bladed screwdriver slot for operation. |

| | |

| |d) The fixed maximum liquid level gauge (vent valve) shall have the vent stem retained, such as by staking or crimping, so that it cannot |

| |be removed from the valve body by reverse rotation. |

| | |

| |Exception: Valves intended for use on cylinders used in industrial truck service (including forklift truck cylinders) and cylinders |

| |identified and used in industrial welding and cutting gas applications, are not required to comply with the requirements noted in (a), |

| |(b), and (c) above. |

|11.6 |The valve stem shall be so constructed so that it shall not fracture, break, crack or have threads stripped, in the open and closed |

| |position when subjected to the Valve Stem Torque Test, Section 24. For handwheel equipped valves, the handwheel shall not break or crack |

| |during this test. |

|Sec 24 |24 Valve Stem Torque Test |

| | |

| |24.1 Six production samples shall be tested, three each in the opened and closed position and comply with 11.6. The torque that shall be |

| |applied to each sample shall be in accordance with Table 24.1 or 150 in-lbs whichever is less. |

| | |

| |Exception: For medical gas or breathing air applications, if the valve is designed for an intentional failure mode (i.e. handwheel or |

| |stem) less than the above requirements the manufacturer shall state the maximum torque value in its literature and the valve shall be |

| |tested at the stated value. |

| | |

| |Table 24.1 |

| |Torque values |

| |Valve type |

| |Torque value (in-lbs) |

| | |

| |Valve with handwheel |

| |T = 50 x D (handwheel diameter in inches) |

| | |

| |Wrench operated valve |

| |T = 750 x L (linear distance across wrench flats) |

| | |

| | |

| |24.2 A torque wrench shall be applied to the valve wrench flat or handwheel, as appropriate and torque be applied in the closed position. |

| | |

| |24.3 A torque wrench shall be applied to the valve wrench flat or handwheel, as appropriate and torque be applied in the opened position. |

|Sec 17 |17 Hydrostatic-Pressure Test |

| |17.1 All parts of a valve, including the check modules on CGA 791 and CGA 810 connections, shall withstand, without rupture or permanent |

| |distortion, a hydrostatic pressure as specified in Table 17.1 for a minimum of one minute. The valve shall be pressurized from the inlet |

| |side of the valve. ″Without permanent distortion″ is defined as compliance with the requirements of the External Leakage Test, Section 14.|

| |Pressure relief device portions of the valve are exempt from this requirement. |

|Sec 20 |20 Accelerated Hydrogen-Pressure Aging Test |

| |20.1 An elastomeric part is to be subjected to hydrogen gas as described in 20.2. After conditioning, the part shall not crack, blister, |

| |or show visible deterioration. |

| | |

| |20.2 An elastomeric part is to be exposed for 14 days to hydrogen gas at a pressure of 300 ±15 psig (2068 ±103 kPa) and at a temperature |

| |of 80 ±1°C (168 ±1.8°F) in accordance with the Standard Test Method for Rubber – Deterioration by Heat and Oxygen, ASTM D572, except that |

| |hydrogen gas is substituted for oxygen gas in the description. |

|Sec 21 |Table 21.1 |

| |Test liquids for elastomeric rubber materials |

| | |

| |Gas in contact with part |

| |Test liquid |

| | |

| |Anhydrous ammonia |

| | |

| |Liquefied Petroleum Gas (LP-Gas) |

| | |

| |Methylacetylene-Propadiene Stabilized (MPS-Gas) |

| | |

| |Manufactured, natural gas, and hydrogen gas |

| |Added hydrogen effective June 30, 2008 |

| | |

| |Propylene Liquid propylene |

| | |

| |Liquid anhydrous ammonia |

| | |

| |n-Hexane |

| | |

| |Liquid MPS-Gas |

| | |

| |IRM 903 Oil and n-Hexane |

| | |

| |Liquid propylene |

| | |

| | |

| | |

|Sec 25 |25 BTU Flow Rating Test |

| |25.1 Three samples shall be submitted to determining the flow rating of the LP Gas OPD/cylinder valve combination for vapor withdrawal. |

| | |

| |25.2 The valve/OPD assembly shall be installed into a system of adequate capacity and pressure that includes a flowmeter, control valve(s)|

| |and a manifold. The system shall be charged and maintained at 10 psig (0.069 MPa) pressure using compressed air or nitrogen. An adapter |

| |having no flow restrictor and having a minimum 0.179 ±0.005 in. (4.5 ±0.13 mm) passageway shall be connected to the valve outlet. No |

| |other valve or device shall be connected to the adapter. The system shall be pressurized and the flow capacity shall be recorded at 1 |

| |minute and 3 minutes. |

| | |

| |25.3 The SCFH shall be converted to BTU/HR propane vapor by the following formula: |

| | |

| |SCFH x 0.81 x 2500 = BTU/HR |

| | |

| |25.4 The valve/OPD assembly shall have a minimum of 150,000 BTU/HR output at 10 psig (0.069 MPa) inlet pressure . |

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