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Parts & Service: 020 8988 7400 / E-mail: Parts@clarkeinternational.com or Service@clarkeinternational.com

TOXIC FUME PREVENTION

Severe discomfort, illness or death can result from fumes, vapours, heat, or

oxygen enrichment or depletion that welding (or cutting) may produce.

Prevent them with adequate ventilation. NEVER ventilate with oxygen. Lead-,

cadmium-, zinc-, mercury- and beryllium-, bearing materials, when welded (or

cut) may produce harmful concentrations of toxic fumes. Adequate local

exhaust ventilation must be used, or each person in the area as well as the

operator must wear an air- supplied respirator. For beryllium, both must be

used. Metals coated with or containing materials that emit toxic fumes should

not be heated unless coating is removed from the work surface, the area is

well ventilated, or the operator wears an air-supplied respirator. Work in a

confined space only while it is being force ventilated and, if necessary, while

wearing an air-supplied respirator. Vapours from chlorinated solvents can be

decomposed by the heat of the arc (or flame) to form PHOSGENE, a highly

toxic gas, and other lung and eye irritating by-products. The ultraviolet

(radiant) energy of the arc can also decompose trichloroethylene and

perchloroethylene vapours to form phosgene. DO NOT WELD where solvent

vapours can be drawn into the welding atmosphere or where the radiant

energy can penetrate to atmospheres containing even minute amounts of

trichloroethylene or perchloroethylene.

FIRE AND EXPLOSION PREVENTION

Causes of fire and explosion are:

1. Combustibles reached by the arc, flying sparks, hot slag or heated

material;

2. Short circuits.

BE AWARE that flying sparks or falling slag can pass through cracks, along

pipes, through windows or doors, and through wall or floor openings, out of

sight of the goggled operator.

To prevent fires and explosion: keep equipment clean and operable, free of

oil, grease, and (in electrical parts) of metallic particles that can cause short

circuits. If combustibles are in the area, DO NOT weld. Move the work if

practicable, to an area free of combustibles.

Avoid working in paint spray rooms, dip tanks, storage areas, ventilators. If the

work cannot be moved, move combustibles away from sparks and heat; or

protect against ignition with suitable fire- resistant covers or shields.

Walls, ceilings, and floor near work should be protected by heat resistant

covers or shields. Fire watcher must be standing by with suitable fire

extinguishing equipment during and for some time after welding or cutting if:

1. Appreciable combustibles (including building construction) are within 10m.

2. Appreciable combustibles are further than 10m, but can be ignited by

sparks.