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SAFETY
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WELDING SPARKS can cause fire or explosion.
4.a. Remove fire hazards from the welding area. If this is not possi- ble, cover them to prevent the welding sparks from starting a fire. Remember that welding sparks and hot materials from welding can easily go through small cracks and openings to adjacent areas. Avoid welding near hydraulic lines. Have a fire extinguisher readily available.
4.b. Where compressed gases are to be used at the job site, special precautions should be used to prevent hazardous situations. Refer to “Safety in Welding and Cutting” (ANSI Standard Z49.1) and the operating information for the equipment being used.
4.c. When not welding, make certain no part of the electrode circuit is touching the work or ground. Accidental contact can cause overheating and create a fire hazard.
4.d. Do not heat, cut or weld tanks, drums or con- tainers until the proper steps have been taken to insure that such procedures will not cause flam- mable or toxic vapors from substances inside. They can cause an explosion even though they have been “cleaned”. For information, purchase “Recommended Safe Practices for the Preparation for Welding and Cutting of Containers and Piping That Have Held Hazardous Substances”, AWS F4.1 from the American Welding Society (see address above).
4.e.Vent hollow castings or containers before heat- ing, cutting or welding. They may explode.
4.f.Sparks and spatter are thrown from the welding arc. Wear oil free protective garments such as leather gloves, heavy shirt, cuffless trousers, high shoes and a cap over your hair. Wear ear plugs when welding out of position or in confined places. Always wear safety glasses with side shields when in a welding area.
4.g.Connect the work cable to the work as close to the welding area as practical. Work cables con- nected to the building framework or other loca- tions away from the welding area increase the possibility of the welding current passing through lifting chains, crane cables or other alternate cir- cuits. This can create fire hazards or overheat lifting chains or cables until they fail.
ELECTRIC SHOCK can kill.
5.a.The electrode and work (or ground) circuits are electrically “hot” when the welder is on. Do not touch these “hot” parts with your bare skin or wet clothing. Wear dry,
5.b. Insulate yourself from work and ground using dry insulation. Make certain the insulation is large enough to cover your full area of physical contact with work and ground.
In addition to the normal safety precautions, if welding must be performed under electrically hazardous conditions (in damp locations or while wearing wet clothing; on metal structures such as floors, gratings or scaffolds; when in cramped positions such as sitting, kneeling or lying, if there is a high risk of unavoidable or accidental contact with the workpiece or ground) use the following equipment:
•Semiautomatic DC Constant Voltage (Wire) Welder.
•DC Manual (Stick) Welder.
•AC Welder with Reduced Voltage Control.
5.c. In semiautomatic or automatic wire welding, the electrode, electrode reel, welding head, nozzle or semiautomatic welding gun are also electrically “hot”.
5.d. Always be sure the work cable makes a good elec- trical connection with the metal being welded. The connection should be as close as possible to the area being welded.
5.e. Ground the work or metal to be welded to a good electrical (earth) ground.
5.f. Maintain the electrode holder, work clamp, welding cable and welding machine in good, safe operating condition. Replace damaged insulation.
5.g. Never dip the electrode in water for cooling.
5.h. Never simultaneously touch electrically “hot” parts of electrode holders connected to two welders because voltage between the two can be the total of the open circuit voltage of both welders.
5.i. When working above floor level, use a safety belt to protect yourself from a fall should you get a shock.
5.j. Also see Items 4.c. and 1.
MAR95