Oxy-Fuel Torch Setup & Shutdown

An oxy-fuel torch mixes oxygen with acetylene, propane or another fuel gas to cut, heat and weld. Setting it up and shutting it down in the right order prevents leaks, flashbacks and cylinder fires. Always follow your equipment maker’s instructions.

• Welders & fabricators
• Pipefitters
• Mechanics

Setup

1. Secure the cylinders upright, chained to a cart or structure.
2. Inspect regulators, hoses, torch and fittings for damage, oil and grease. Never use oil on oxygen equipment.
3. Crack the cylinder valves briefly to blow out dirt, standing to the side and away from any ignition source.
4. Attach regulators. Oxygen fittings have right-hand threads; fuel gas fittings have left-hand threads (usually a notched nut).
5. Install flashback arrestors and check valves as the maker requires. See Flashback Arrestors.
6. Connect hoses: in the U.S., usually green for oxygen and red for fuel gas.
7. Back out the regulator adjusting screws, then open cylinder valves slowly, standing to the side of the regulator, not in front of it.
8. Open the acetylene valve no more than about 1½ turns, and leave the valve wrench on the cylinder if it doesn’t have a handwheel.
9. Set working pressures. Never use acetylene above 15 psi; it can become unstable.
10. Purge each hose briefly, one at a time, in a ventilated area.
11. Leak test all connections with leak-test solution. Never use a flame.

Lighting

• Use a friction striker, never matches or a lighter.
• Point the torch away from people, cylinders and combustibles.
• Follow the maker’s lighting sequence, and adjust to a neutral flame for most work.

Shutdown

1. Close the torch valves in the order your equipment maker specifies.
2. Close both cylinder valves.
3. Open the torch valves one at a time to bleed the lines, then close them.
4. Back out the regulator adjusting screws.
5. Coil hoses and store the outfit safely. For long breaks or transport, remove regulators and install valve caps.

PPE

• Cutting goggles or a face shield with the right shade (usually 3 to 5). See Eye & Face Protection
• Flame-resistant clothing and leather gloves
• Safety-toe boots, with pant legs over the boot tops
• Fire extinguisher and fire watch as the hot work permit requires

Last updated: October 2, 2026