Safety considerations, Electric arc welding equipment – MK Products Cobramatic 42VAC User Manual
Page 3
Cobramatic
®
Safety - page i
SAFETY CONSIDERATIONS
ELECTRIC ARC WELDING EQUIPMENT
CAUTION : READ BEFORE ATTEMPTING INSTALLATION, OPERATION
OR MAINTENANCE OF THIS EQUIPMENT
1-1 INTRODUCTION
This equipment is intended for ultimate
application by commercial/industrial users
and for operation by persons trained and
experienced in the use and maintenance of
welding equipment. Operation should not be
undertaken without adequate training in the
use of such equipment. Training is available
from many public and private schools or similar
facilities.
Safe practices in the installation, operation
and maintenance of this equipment requires
proper training in the art, a careful study of the
information provided with the equipment, and
the use of common sense. Rules for safe use
are generally provided by suppliers of welding
power sources, compressed gas suppliers,
and electrode suppliers. Careful compliance
with these rules will promote safe use of this
equipment.
The following Safety Rules cover some of the
more generally found situations. READ THEM
CAREFULLY. In case of any doubt, obtain
qualified help before proceeding.
1-2 GENERAL PRECAUTIONS
A. B
urn
P
revention
ELECTRIC ARC WELDING PRODUCES
HIGH INTENSITY HEAT AND ULTRAVIOLET
RADIANT ENERGY WHICH MAY CAUSE
SERIOUS AND PERMANENT EYE DAMAGE
AND WHICH MAY DAMAGE ANY EXPOSED
SKIN AREAS.
Wear helmet with safety goggles or glasses
with side shields underneath, appropriate filter
lenses or plates (protected by clear cover
glass). This is a must for welding or cutting
(and chipping) to protect the eyes from radiant
energy and flying metal. Replace cover glass
when broken, pitted, or spattered.
Medical first aid and eye treatment. First aid
facilities and a qualified first aid person should
be available for each shift unless medical
facilities are close by for immediate treatment
of flash burns of the eyes and skin burns.
Wear protective clothing - leather (or asbestos)
gauntlet gloves, hat, and high safety-toe shoes.
Button shirt collar and pocket flaps, and wear
cuffless trousers to avoid entry of sparks and
slag.
Avoid oily or greasy clothing. A spark may
ignite them.
Flammable hair preparations should not be
used by persons intending to weld or cut.
Hot metal such as electrode stubs and work
pieces should never be handled without gloves.
Ear plugs should be worn when working on
overhead or in a confined space. A hard hat should
be worn when others work overhead.
B. t
oxic
F
ume
P
revention
WARNING: The use of this product may result
in exposure to chemicals known to the State of
California to cause cancer and birth defects or
other reproductive harm.
Adequate ventilation. Severe discomfort, illness
or death can result from fumes, vapors, 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-, beryllium-bearing
and similar 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 form 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
ventilated and, if necessary, while wearing an air-
supplied respirator.
Gas leaks in a confined space should be avoided.
Leaked gas in large quantities can change oxygen
concentration dangerously. Do not bring gas
cylinders into a confined space.
Leaving confined space, shut OFF gas supply at
source to prevent possible accumulation of gases
in the space if downstream valves have been
accidentally opened or left open. Check to be sure
that the space is safe before reentering it.
Vapors 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 products. The ultraviolet
(radiant) energy of the arc can also decompose
trichloroethylene and perchloroethylene vapors
to form phosgene. DO NOT WELD or cut where
solvent vapors can be drawn into the welding or
cutting atmosphere or where the radiant energy can
penetrate to atmospheres containing even minute
amounts of trichloroethylene or perchloroethylene.
c. F
ire
And
e
xPlosion
P
revention
Causes of fire and explosion are: combustibles
reached by the arc, flame, flying sparks, hot slag,
or heated material, misuse of compressed gases
and cylinders, and 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
can fly many feet.
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 35 feet away, out of reach of sparks and
heat; or protect against ignition with suitable
and snug-fitting, fire-resistant covers or shields.
Walls touching combustibles on opposite
sides should not be welded on (or cut).
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 35 feet.
2. Appreciable combustibles are further than
35 feet, but can be ignited by sparks.
3. Openings (concealed or visible) in floors or
walls within 35 feet may expose combustibles
to sparks.
4. Combustibles adjacent to walls, ceilings,
roofs, or metal partitions can be ignited by
radiant or conducted heat.
Hot work permit should be obtained before
operation to ensure supervisor’s approval that
adequate precautions have been taken.
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 vapors
when heated, must never be welded on or
cut, unless container has first been cleaned in
accordance with industry standards.
This includes: a thorough steam or caustic
cleaning (or a solvent of 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