USER’S MANUAL
EN
4
Arc welding and allied processes produce wel-
ding fume which may pollute the atmosphere
surrounding the work. Welding fume is a vary-
ing mixture of airborne gases and fine particles
which, if inhaled or swallowed, constitute a
health hazard.
The degree of risk is depend on:
• the composition of the fume;
• the concentration of the fume;
• the duration of exposure.
A systematic approach to the assessment of
exposure is necessary, taking into account the
particular circumstances of the operator and the
ancillary worker who can be exposed.
Welding fume may be controlled by a wide
range of measures, e.g. process modifications,
engineering controls, methods of work, personal
protection and administrative action.
First it is necessary to consider whether ex-
posure can be prevented by eliminating the
generation of welding fume altogether. Where
this cannot be done, measures for reducing the
quantity of welding fume generated should be
investigated, after which the control of welding
fume at source should be considered. The use
of respiratory equipment should not be con-
templated until all other possibilities have been
eliminated. Normally, respiratory protective
equipment should be used only as an interim
measure. However, there cannot be a situation
in which, in addition to ventilation, the use of
personal protection is necessary.
1.4.1 VAPOURS AND GASES.
ADDITIONAL PRECAUTIONS
• Welding operations can involve generation
of vapours and gases that are hazardous
to health. Inhaling the vapours should be
avoided. Keep your head away from vapours
during welding operations. Ensure proper
ventilation and/or mechanical welding ex-
haust draught to keep vapours and gases
away from the breathing zone.
• When welding is carried out in a confined
space, operators should only be permitted
to weld when other persons, who have
been instructed and who are able to react
in case of an emergency, are in the imme-
diate vicinity.
• In closed rooms or in certain circumstances
during outdoor operations, it may be re-
quired to use individual equipment for the
protection of the welder’s airways, e.g. a re-
spirator. Additional safety measures are also
required when galvanized steel is welded.
• Welding operations must not be performed
in the vicinity of chlorinated hydrocarbons
generated during degreasing, cleaning or
spraying. Heat and radiation generated
by the arc may enter into a reaction with
vapours of solvents, which may lead to the
formation of phosgene – a highly toxic gas.
• The shielding gas used during arc welding
may force the air out of a room. This may
lead to a health hazard or even death. Pro-
per ventilation, especially in closed rooms,
should always be provided, to ensure appro-
priate amount of air that is indispensable for
safe breathing.
1.5
NOISE CAN BE HARMFUL
In the welding environment, damaging levels of
noise can exist. Continued exposure to a high
noise level on the unprotected ear is injurious.
The noise levels should be reduced to the lo-
west practicable level.
High levels may be tolerated for very short
periods by wearing adequate ear protection in
accordance with the national or local regulation.
In case of doubt, checks by an expert should be
made to establish noise levels in any particular
environment, and, if these are in excess of the
prescribed limit, one of the following alterna-
tives may apply:
a) insulation of the noise source as far as po-
ssible, e.g. by fitting silencers or sound proof
enclosures,
b) insulation of the operator from the noise
