Arc

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Arc Welding Safety Notes
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Before starting actual arc welding the student
should be fully aware of the dangers involved.
The high temperature arc and hot metal can cause
severe burns. In addition the electric arc
itself provides an additional safety hazard.
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The electric arc emits large amounts of ultra
violet and infra-red rays. Both types of rays
are invisible to the naked eye just as the same
type of rays emitted by the sun are invisible.
However they both have the identical properties
of causing sunburn on the human skin, except that
the arc burns much more rapidly and deeply.
Since these rays are produced very close to the
operator they can cause very severe burns to the
eyes in a short exposure time.
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When welding with the electric arc, there is
added danger that the small globules or droplets
of molten metal may leave the arc and fly in all
directions. These so called sparks range in
temperature from 2000 to 3000 Fahrenheit and
in size from very small to as large as ¼ inch.
They present a personal burn hazard plus a fire
hazard if they fall in inflammable material.
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The welding operator needs to protect himself,
by means of a helmet and other protective devices
from the harmful rays of the arc and flying
sparks. The filter plates in the welding helmet
will remove 99 of the harmful rays if the proper
shade lens is used.
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Other dangers associated with electric arc
welding are a. Electric shock-which may be
caused by standing in damp areas, welding without
gloves, bare cables, uninsulated holder, etc. b.
Harmful fumes given off in welding process
especially when welding on galvanized or other
coated materials.
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The operator should be familiar with all safety
precautions and take care to adequately protect
himself at all times against any hazards
associated with arc welding by wearing protective
clothing and equipment, working in dry
conditions, providing adequate ventilation and in
general using good common sense.
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Following is a list of safety precautions that
should be observed in the use of the arc welding
equipment.
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a. Electric Shock

• Make sure machine is properly grounded.
• Never permit live parts of the electric welder
  to touch bare skin or wet clothing.
• Do not cool electrode holders by emersion in
  water.
• Turn off power supply when welder is not in use.
• Do not stand on wet areas while welding.
• Wear leather gloves.
• Make sure cable are covered and in good
  condition.
• Make certain that electrode holders are properly
  insulated.

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b. Burns

• Protect eyes and face from flying particles of
  slag by use of safety glasses or face shield.
• Wear adequate protective clothing.
• Always wear leather gloves.
• Wear high top shoes.
• Keep collar, shirt pockets, etc buttoned.
• Do not touch the electrode or metal where welding
  has taken place.
• Handle hot metal with pliers or tongs.
• Keep electrode stubs properly disposed of.

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c. Radiant Energy (utlra violet rays, etc.)

• Use a welding helmet with the correct shade lens
  in good condition.
• Wear suitable clothingdo not leave bare skin
  exposed to the rays of the arc.
• Do not strike the arc without covering the face
  and eyes. Give warning to others before striking
  the arc.
• Avoid looking directly at the arc where others
  are welding without proper eye protection.

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d. Gases and Fumes

• Work only in well-ventilated areas.
• Use great care when working on metals covered
  with lead or zinc.
• If working in a confined area use respirator or
  other approved breathing devices.

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e. Combustible Materials

• Keep shop clean in areas where welding is to be
  done.
• Do not weld near combustible materials of any
  kind.
• Never weld on covered containers which may have
  held combustible materials without first taking
  adequate safety precautions. For example, fill
  them with water, steam clean or fill with an
  inert gas.

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f. Fire Protection

• Be familiar with location and types of fire
  extinguishers.
• Report any unsafe conditions that might start a
  fire.
• Do not weld near inflammable materials.
• Do not weld on containers that have held
  inflammable materials.
• Do not weld near electrical fittings or lines.