Helvi 6013 Manual De Uso página 5

This pane can be frequently replaced when
incandescent spatters and deposits greatly
reduce visibility. When working with coated
plates that emit toxic fumes when heated,
use an air-supplied respirator.
- Welding should be done in a closed area
that does not open onto other working areas,
in order to protect all workers against radia-
tion and fumes. If such an area cannot be
provided, the welding area must be delimi-
ted by protective screens painted in opaque
black large enough to restrain the visibility of
any person situated near the area (Fig. 3).
- Remove all chlorinated solvents from the
welding area before welding. Certain chlori-
nated solvents decompose when exposed to
ultraviolet radiation to form phosgene gas.
- Never, under any circumstances, look at
an electric arc without suitable eye protection
(Fig. 4).
- Always wear protective goggles with tran-
sparent lenses to prevent splinters or other
foreign particles from harming the eyes (Fig.
5).
- Adequate local exhaust ventilation must
be used in the area. It should be provided
through a mobile hood or through a built-
in system on the workbench that provides
exhaust ventilation from the sides, the front
and below, but not from above the bench so
as to avoid raising dust and fumes. Local
exhaust ventilation must be provided toge-
ther with adequate general ventilation and
air circulation, particularly when work is done
in a confi ned space. (Fig.6). Any symptom of
stain or soreness to the eyes, the nose or the
throat may be cause by inadequate ventila-
tion; work must be stopped immediately and
all necessary steps must be taken to provide
adequate ventilation.
- Welding process must be performed on
metal coatings thoroughly cleaned from la-
yers of rust or paint, to avoid production of
harmful fumes. The parts degreased with a
solvent must be dried before welding.
- Do not weld metal or painted metal con-
taining zinc, lead, cadmium or beryllium un-
less the operator, or anyone else subjected to
the fumes, is wearing respiratory equipment
or an air-supplied helmet.
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