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Subchapter 4. Construction Safety Orders
Article 32. Oxygen, Acetylene, and Fuel Gas

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§1740. Storage and Use of Cylinders.

(a) All gas cylinders shall be protected against undue absorption of heat.
(b) Acetylene and Fuel gas cylinders, including but not limited to welding and cutting fuel gas cylinders, shall be stored and used with the valve end up.
Exception: Fuel gas cylinders containing fuel gas used to power industrial trucks regulated by Article 25 of the General Industry Safety Orders.
Cylinders containing oxygen, acetylene or fuel-gases shall not be taken into confined spaces.
(c) Gas cylinders in portable service shall be conveyed by suitable hand trucks to which they are securely fastened, or safely carried where job conditions require. All gas cylinders in service shall be securely held in substantial fixed or portable racks, or placed so they will not fall or be knocked over.
Valve protection caps, when provided for, shall be put in place before cylinders are moved, transported or stored.
(d) Gas cylinders raised or lowered by crane, hoist, or derrick must be handled in suitable cradles, nets, or skip boxes, and shall never be lifted by magnet or by rope or chain slings.
(e) Cylinders must not be placed where they might form a part of any electric circuit.
(f) No attempt shall be made to transfer acetylene from one cylinder to another, or to mix gases in a cylinder.
(g) Oxygen cylinders in storage shall be separated from fuel-gas cylinders or combustible materials (especially oil or grease), a minimum distance of 20 feet or by a noncombustible barrier at least 5 feet high having a fire-resistance rating of at least one-half hour.
(h) Cylinders shall be kept far enough away from the actual welding or cutting operation so that sparks, hot slag, or flame will not reach them. When this is impractical, fire resistant shields shall be provided.
(i) LP-Gas vessels used for roofer's tar pots, plumber's pots and torches, space heaters, etc., shall be so installed that heat from the burner will not increase the temperature of the tank more than 10 degrees Fahrenheit after one hour of operation of the burner at full capacity.
(j) LP-Gas vessels installed on mobile equipment shall have the bottom of the container, and/or any outlet connection, not lower than the lowest horizontal edge of the vehicle axle when fully loaded. Such units shall be adequately secured to prevent jarring loose, slipping, or rotating.
(k) Use of Fuel Gas.
(1) The employer shall instruct employees in the safe use of fuel gas.
(2) Before a regulator to a cylinder valve is connected, the valve shall be opened slightly and closed immediately. (This action is generally termed “cracking” and is intended to clear the valve of dust or dirt that might otherwise enter the regulator.)
(3) The person cracking the valve shall stand to one side of the outlet, not in front of it. The valve of a fuel gas cylinder shall not be cracked where the gas would reach welding work, sparks, flame, or other possible sources of ignition.
(l) The cylinder valve shall be opened slowly to prevent damage to the regulator. For quick closing, valves on fuel gas cylinders shall not be opened more than 1 1/2 turns. When a special wrench is required, it shall be left in position on the stem of the valve while the cylinder is in use so that the fuel gas flow can be shut off quickly in case of an emergency. In the case of manifolded or coupled cylinders, at least one such wrench shall be available for immediate use. Nothing shall be placed on top of a fuel gas cylinder, when in use, which may damage the safety device or interfere with the quick closing of the valve.
(m) When the valve on a fuel gas cylinder is opened and there is found to be a leak around the valve stem, the valve shall be closed and the gland nut tightened. If this action does not stop the leak, the use of the cylinder shall be discontinued, and it shall be properly tagged and removed from the work area. In the event that fuel gas should leak from the cylinder valve, rather than from the valve stem, and the gas cannot be shut off, the cylinder shall be properly tagged and taken outdoors, to an isolated area, away from personnel and sources of ignition. The supplier shall promptly be notified of the leaking cylinder valve and the supplier's instructions shall be followed.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
1. Amendment filed 5-21-75; effective thirtieth day thereafter (Register 75, No. 21).
2. Amendment filed 1-5-87; effective thirtieth day thereafter (Register 87, No. 2).
3. Amendment of subsection (m) filed 1-6-99; operative 2-5-99 (Register 99, No. 2).
4. Amendment of subsection (b) filed 8-21-2007; operative 9-20-2007 (Register 2007, No. 34).

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