7
SAFETY INFORMATION
5.
Work in a confined space only if it is well
ventilated, or while wearing an air-supplied
respirator.
Shielding gases used for welding can
displace air causing injury or death. Be sure
the breathing air is safe.
6.
Do not weld in locations near degreasing,
cleaning, or spraying operations. The heat
and rays of the arc can react with vapors to
form highly toxic and irritating gases.
7.
Do not weld on coated metals, such as
galvanized, lead, or cadmium plated steel,
unless the coating is removed from the weld
area, the area is well ventilated, and if
necessary, while wearing an airsupplied
respirator. The coatings and any metals
containing these elements can give off toxic
fumes if welded.
Noise
Welding environments are frequently
noisy as other operations such as
grinding, etc. may also be taking
place. Some operations, such a de-
slagging may take the noise up to
such a level where it will damage hearing. In
such cases hearing protection must be used.
Fire and Explosion Prevention
Causes of fire and explosion are:
1) combustibles reached by the arc,
flame, flying sparks, hot slag or
heated material;
2) misuse of compressed gases and cylinders;
3) 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.
Sparks and slag can fly 10M.
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 area, do NOT weld or cut.
Move the work if practicable, to an area free of
combustibles.
Avoid paint spray rooms, dip tanks, storage
areas, ventilators. If the work cannot be moved,
move combustibles at least 10M, away out of
reach of sparks and heat; or protect against
ignition with suitable and snug fitting, 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:
a) appreciable combustibles (including building
construction) are within 10m.
b) appreciable combustibles are further than
10m but can be ignited by sparks.
c) openings (concealed or visible) in floors or
walls within 10m can expose combustibles to
sparks.
d) combustibles adjacent to walls, ceilings, roofs
or metal partitions can be ignited by radiant
or conducted heat.
After work is done, check that area is free of
sparks, glowing embers, and flames.
An empty container that held combustibles, or
that can produce flammable or toxic vapours
when heated, must never be welded on or cut,
unless container has first been cleaned. This
includes a thorough steam or caustic cleaning
(or a solvent or water washing, depending on
the combustible’s solubility) followed by purging
and inerting with nitrogen or carbon dioxide,
and using protective equipment.
Water filling just below working level may
substitute for inerting.
A container with unknown contents should be
cleaned (see paragraph above), do NOT depend
on sense of smell or sight to determine if it is
safe to weld or cut.
Hollow castings or containers must be vented
before welding or cutting - they can explode.
In explosive atmospheres, never weld or cut
where the air may contain flammable dust, gas,
or liquid vapours.