By Robert J. Maloney
Regardless of the type of torch used, “I just need to be able to cut one thing into two or more pieces,” Thomas Kenney told students at the Thursday morning class, “Fire and Rescue Cutting Torch Operations.” Torch types, components, fuels, safe handling, and operations were the focus.
A lieutenant with the Hyannis (MA) Fire Department, Kenney has attended FDIC for about nine years, and has taught in a heavy building collapse HOT class. He co-developed a HOT class for cutting torches one year, and since then has taught the torch cutting classroom session. “FDIC is the Super Bowl for teaching,” he said.
In torch cutting, fuels such as acetylene, propane, natural gas, propylene, gasoline are mixed with oxygen to produce the cutting flame.
“You’ve got to have a great respect for acetylene,” he said regarding the highly flammable fuel. In an incident in New Hampshire, a leaking acetylene tank was left in a car trunk overnight. Because the acetylene valve was left open, the gas accumulated in the confined space overnight. The next morning, an explosion resulted when the car’s owner pressed the vehicle’s remote starter. Photos show the rear of the car entirely destroyed, as well as damage to an adjacent mobile home, including damaged siding and shattered windows.
Kenney reviewed the types of acetylene and oxygen tanks and valve threading on which may be either male or female, depending on the manufacturer and type. Hoses are color coded green for oxygen, and red for the gas fuel lines, which are distinguished by notches on the metal fittings. Also discussed were proper ignition, oxygen/fuel pressure setting and regulation to produce the appropriate cutting flame.
Tip charts list the thickness of the piece to be cut, the appropriate torch tip size, and relevant oxygen and fuel pressure settings, and are available from manufacturers.
Kenney also touched on other torch types. Gasoline torch systems must always use fresh fuel or they will not operate. Exothermic torches use carbon steel rods with a center tube for the oxygen. They are ignited using a striker powered by a 12-volt battery, which is a drawback to the system if the battery is weak.
When cutting metal, Kenney said, always use appropriate personal protective equipment, particularly eye and ear protection. Use an appropriate USAR or leather coat (slag will burn through ordinary turnout gear), ear plugs, torch shade 5 eye goggles to cover the eyes completely, and leather gloves to protect from the slag produced in the cutting process. A firefighter helmet face shield is inadequate to protect the eyes because it is open and the eyes are not fully protected. Only ignite the torch when full protective gear is in place.
