General Precautions; Fire Prevention; Toxic Fumes; Electric Shock - USAG 998 140A Manual Del Usuario

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1.2 GENERAL PRECAUTIONS

1.2.1 Prevention of burns
Sparks, slag, hot metal and radiations produced by the welding arc can be seriously damaging to the eyes and skin. As the
operator or any other person comes close to the welding area, the level of exposure increases rapidly. Proper protective
clothing and equipment must be worn by the operator and any other persons working in the vicinity of the arc. Gauntlet
gloves designed for use in welding, safety shoes, and a hat are required. Flame retardant clothing which covers all exposed
areas and cuffless trousers to prevent entry of sparks and slag are recommended. Proper safety goggles or glasses with side
shields of the appropriate welding lens shade MUST be worn to protect the operator's eyes from radiant energy and flying
sparks or hot metal.

1.2.2 Fire prevention

Since electric welding arc produces hot metal, sparks, and slag, precautions must be taken to prevent fire and/or explosions.
Make sure that appropriate fire extinguishing equipment is available in the immediate welding area. All combustible
materials must be removed from the immediate welding area to a distance of at least 10 meters(35 feets) away. Never arc
weld empty containers which have held toxic or potentially explosive materials. Those containers must be thoroughly
cleaned prior to welding. Never arc weld in an atmosphere which contains heavy concentrations of dust, flammable gas, or
combustible liquid vapors(such as gasoline). After each welding operation make sure to let welded material to cool down
before touching it or putting it in contact with combustible or flammable materials.

1.2.3 Toxic Fumes

Proper precautions must be exercised to prevent the exposure of the operator or others in the surrounding area to possible
toxic fumes which may be generated during electric are welding.
Certain chlorinated solvents will decompose under ultraviolet radiations to form phosgene gas. Care must be exercised to
avoid the use of these solvents on materials being weld with electric arc welding equipment. Containers of these solvents
and other degreasing agents must be removed from the immediate area near the welding arc.
Metals coated with or containing significant amounts of lead, cadmium, zinc, mercury, and beryllium can produce harmful
concentration of toxic fumes when subject to electric arc welding operations. Adequate local exhaust ventilation must be
used or the operator must be wearing special equipment to guarantee a supply of fresh air as a respirator or air supplied
helmet.
Do not weld metals coated with materials which emit toxic fumes unless 1) the coating is removed prior to welding, 2) the
area is adequately ventilated, or 3) the operator is supplied with fresh-air breathing equipment.
1.2.4 Radiation
Ultra-violet radiations created by the arc may be harmful to the eyes and burn the skin; it is therefore imperative to wear
protective clothing and helmet.
Contact lenses should not be used as the intense heat coming from the arc may cause them to stick to the cornea.
The mask used during welding should be equipped with grade DIN 10 safety lenses at least and they should immediately be
replaced whenever damaged or broken.
Since the arc may damage the eyes it is considered dangerous up to a distance of 15 meters (50 feets) and it should never be
locked at with the naked eye.

1.2.5 Electric shock

All electric shocks are potentially fatal and therefore live wires and/or parts should never be touched.
Insulation must be kept from the piece to be welded and from the ground by wearing insulation gloves and clothing.
Garments such as gloves, shoes, hats, clothings and body must be kept dry at all times and it is to be avoided working in
humid or wet areas.
Never touch or hold the piece to be welded by hand; if the slightest electric shock is felt, welding should be stopped
immediately; the unit is not to be used until the problem is identified and solved by qualified personnel.
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