Welders
All Welders who use electrical systems to “Weld, Cut, or Braze” must have a working knowledge of the
electrical hazards that’s an inherent part of their job and take positive steps to eliminate and/or mitigate
those hazards – see Figure below. The following are some of the safety rules and guidelines that apply to
welders and may be used in other disciplines.
because the equipment isn't properly grounded, direct contact with energized leads or from
contact with the welding leads via moist gloves or clothing, damp floors or humid air. The
environmental conditions of the welder (such as wet or cramped spaces) may make the likelihood of a
shock greater. Even if the shock itself isn't too serious, the jolt could throw a welder out of position
causing major injuries. Falls and other accidents can result from even a small shock; brain damage and
death can result from a large shock.
Always wear dry hole-free insulating gloves to protect against or reduce electric shock. The welder
should also wear rubber-soled shoes, and use an insulating layer, such as a dry board or a rubber mat, for
protection on surfaces that can conduct electricity.
Arc Welding and Cutting 29 Code of Federal Regulation (CFR) 1910.254(d)(7): Manufacturer’s
Instructions: Printed rules and instruction covering the operation of the equipment supplied by the
manufacturer shall be strictly followed. Mr. Dave Werba, Miller Electric Co. - Technical Support,
stated that “insulating gloves” referred to both protection from heat, sparks, etc. and electrical insulating
properties. He suggested using “Electrical Line-man’s Gloves.”
Ground the piece being welded and the frame of all electrically powered machines. The insulation on
electrode holders and electrical cables should be kept dry and in good condition. Do not change
electrodes with bare hands, wet gloves, when standing on wet floors or grounded surfaces.
Welders must protect themselves and OTHERS in the vicinity from electrical shock. OSHA requires
the welding machines to be turned off when it is left for appreciable/extended periods of time. 29 CFR
1926.351(d)(3): When the arc welder or cutter has occasion to leave his work or to stop work for any
appreciable length of time, or when the arc welding or cutting machine is to be moved, the power supply
switch to the equipment shall be opened.
In order to protect those in the vicinity of welding/plasma arc operations, you must prevent the general
population from coming in contact with the ENERGIZED ELECTRODES – see Figure 17. The
electrode and work circuit is electrically live whenever the output is on (power switch is in the ON
position. 29 CFR1910.254 para (d)(7) and 1926.254: Electrode holders. Electrode holders when not in
use shall be so placed that they cannot make electrical contact with persons, conducting objects, fuel or
compressed gas tanks.
Z49.1 3.2.3.3 Safe Conditions. Welders shall cut or weld only where all safety precautions have been
met.
E3.2.3.3 Do not work alone where conditions are especially hazardous, such as where electric
shock is a hazard, or where ventilation is poor, etc. (Electric Shock is always a hazard and is an
ever present danger!)
3.2.3 Welders
3.2.3.1 Safe Handling of Equipment. Welders shall understand the hazards of the operation to be
performed and the procedures being used to control hazardous conditions. Welders shall handle
the equipment safely and use it so as not to endanger lives and property.
4. Protection of Personnel and the General Area
4.1 Protection of the General Area
4.1.1 Equipment. Welding equipment, machines, cable, and other apparatus shall be located so
that it does not present a hazard to personnel. Good housekeeping shall be maintained.
4.1.2 Signs. Signs shall be posted designating welding areas, and indicating that eye protection
and other applicable protective devices shall be worn.
Personnel assigned to work in areas where there may be electrical hazards, should be informed of the
nature of the hazard and personal protective measures necessary. They must be familiar with protective
equipment, alerting techniques and emergency assistance methods. Para 5.: Use safety signs, tags,barricades or standby attendants as needed to keep unauthorized persons out of a work area where
electrical hazards might exist. A physical barrier is always the preferred method of keeping personnel
away from the dangerous electrical potential/current encountered/available during welding evolutions.
Each welder shall be familiar with the area used for performing welding and shall take the proper
precautions to prevent fires, electrical shock, eye injury, inhalation of hazardous fumes, burns,
excessive noise, and heat exhaustion to themselves and others who may occupy the area.
Specific Electrical Measures
The avoidance of electrical shock is largely within the control of the welder. Therefore, it is especially
important that the welder be thoroughly trained on safe welding procedures. Safe procedures must be
observed at all times when working with equipment having voltages necessary for arc welding. These
voltages can be dangerous to life. Even mild shocks can cause involuntary muscular contractions.
Electric shock from welding can kill!! Any electric welder, AC or DC, has the power to cause
electrocution if the electrode touches your bare skin while you are grounded.
To avoid electric shocks and possible electrocution, personnel should take the following precautions:
• Welders must always be concerned about the possibility of electrical shock. Wet
working conditions must be avoided because water is an excellent conductor and
electricity will always follow the path of least resistance. Even a person’s perspiration
can lower the body’s resistance to electrical shock. Standing on a dry rubber mat, or
when welding outdoors, standing on a dry board, is always advisable.
• Poor connections and bare spots on cables further increase the possibility of electrical
shock, so equipment operators should routinely inspect for effective ground connections.
A proper ground connection is always necessary because it provides a safety connection
from a welding machine frame to the earth.
• Connections typically used for grounding an engine-driven welding machine include a
cable connected from a ground stud on the welding machine to a metal stake
driven/placed into/in the ground.
• The workpiece being welded and the frame or chassis of all electrically powered
machines must be connected to a good electrical ground. This can be accomplished by
connecting it to a properly grounded building frame or other appropriate ground. Chains,
wire ropes, cranes hoists and elevators must never be used as grounding connectors.
• The work lead is not the grounding lead. The work lead connects the work terminal on the power source to the workpiece. A separate lead is required to ground the workpiece
or power source.
• When arc welding equipment is properly grounded, a voltage may exist between the
electrode and any conducting object. Examples of conducting objects include buildings;
power tools, work benches, welding power source cases, and work pieces.
• Never touch the electrode and any metal object unless the welding power source is OFF.
• When installing a welding system, connect the frames of each unit such as welding power
source, control, worktable and water circulator to the building ground. Conductors must
be adequate to carry ground currents safely. Equipment made electrically hot by stray
current may deliver a powerful shock.
• Never ground to an electrical conduit or to a pipe carrying any gas or flammable liquid
such as oil or fuel.
• Use proper precautionary measures and recommended safe practices at all times. Train
personnel using welding and cutting equipment to reduce the risk of injuries, fatalities,
and electrical accidents.
• Read all instructions, labels and installation manuals before installing, operating or
servicing the equipment.
• Do not strike the arc without covering the face and eyes. Give warning to others before
striking the arc.
• All of the following are electrically energized when the power is “on”: electrode and
welding circuit, input power circuit and machine internal circuits, the wire, reel of wire,
drive rolls, and all other metal parts touching the energized electrode.
• Have all installation, operation, maintenance, and repair work performed only by
qualified people.
• Do not work alone.
• Wear dry, hole-free, insulating gloves in good condition and protective clothing.
• Isolate/Insulate yourself from the workpiece and ground by wearing high top rubber
soled shoes or standing on a dry insulated mat or platform.
• Use fully insulated electrode holders. Never dip the holder into water to cool it or lay it
on conductive surfaces or the work surface.
• Do not touch holders connected to two welding machines at the same time.
• Do not allow the holder or electrode to come in contact with any other person.
• Do not use worn, damaged, undersized, or poorly spliced cables, welding gun cables, or
torch cables. Make sure all connections are tight, clean, and dry.
• Do not wrap cables carrying electric current around any part of your body.
• Ground the workpiece to a good electrical earth ground. The work lead is not a ground
lead. Do not use the work lead as a ground lead. Use a separate connection to ground
the workpiece to earth.
• Do not touch an energized electrode while you are in contact with the work circuit.
• When using auxiliary power from welding generators, it is recommended that you use a
circuit protected by a ground fault circuit interrupter (GFCI) such as receptacles in boxes,
extension cords, and the like. Use of an assured grounding system is also acceptable and
is equivalent to use of a GFCI protected circuit.
• In confined spaces or in locations that are electrically hazardous due to water or
perspiration, do not use welding equipment with AC output unless it is also equipped
with a voltage reducer and remote output control. Use equipment with DC output and do
not work alone.
• Additional safety precautions are required when welding is performed under any of the
following electrically hazardous conditions: in damp locations or while wearing wet.
clothing; on metal floors, gratings, scaffolds, or other metal structures; in cramped
positions such as sitting, kneeling, or lying; or when there is a high risk of unavoidable or
accidental contact with the workpiece or ground. Where these conditions are present, use
one of the following types of equipment presented in order of preference:
Semiautomatic DC constant voltage metal electrode (wire) welder,
DC manual covered electrode (stick) welder, or
AC welder with reduced open-circuit voltage. In most situations, use of a DC,
constant voltage wire welder is recommended. And, do not work alone!
Electrodes or welding wire should never be touched with bare hands when in the
holder or welding gun. Holders or welding guns should never be held under the
armpits. Remember, hot work increases risk due to the reduced skin resistance
when sweating occurs.
• Turn off all equipment when not in use.
• Use only well maintained equipment. Repair or replace damaged parts before further
use.
• Wet working conditions should be avoided. Even a person's perspiration can lower the
body's resistance to electrical shock.
Welding can cause other hazardous conditions, such as fires. Always take extra precaution to prevent
all accidents while welding. Simple preventive actions such as placing your welding cables and other
equipment where they will not obstruct passageways, ladders, and stairways will help prevent accidents.
Heavy Equipment Operators
Contact with overhead power lines is a major cause of fatalities in the construction industry. As many
as 100 workers are killed each year by inadvertent power line contacts, most of which occur through the
use of high reaching material-handling equipment. A study of accidents involving power line contacts
has indicated that the use of CRANES is the most common cause of fatalities as seen in Figure below.
It's easy to prevent serious accidents involving cranes and power lines. The following safety tips should
be adhered to when operating a crane near overhead power lines.
• Keep a safe distance between yourself and power lines. Ten feet is generally considered the
minimum safe distance. Always consider all power lines as energized and dangerous. Any
contact with a crane boom will probably cause serious injury to operators and workers, and
damage to equipment.
• Look up before you unload or load a crane from a truck or lowboy. Make sure there are no
overhead lines before you start.
• Educate your crew, particularly new employees about the dangers of overhead power lines.
Utility companies have a ten feet (10' ) minimum approach distance to overhead power lines. This distance is law in some states.
• Be safe! The crane's mast or boom must be kept at least 10 feet away from a normal distribution
power line at all times. And that includes the load line and the load. Skilled crane operators
know that distances in the air are hard to judge, and that a spotter is a good, safe idea. When you
must work near any power line, use the shortest boom possible. Never move a crane under a
power line unless there are adequate clearances.
If your crane boom or mast contacts a power line, the operator should immediately try to swing the
boom into the clear. If it is necessary to leave the equipment, anyone on the machine should jump
entirely clear of the unit. Jump so that both feet hit the ground at the same time, and keep them close
together. Walk away in a small step shuffle because a lot of power flowing into the ground can create
differences in electrical potential around the problem: enough difference to actually shock anyone
whose feet are too far apart. Once clear of the equipment, do not return for any reason until the power
line has been grounded or determined to be safe by your electric utility or the owner of the line. And
keep any others around from touching or approaching the equipment.
Contact with overhead power lines continues as a major cause of electrical accidents, injuries and
fatalities.
Excavators
Buried power and communication lines are more prevalent today than ever before. These lines pose a
special hazard to operators of equipment used during trenching and excavation activities. Therefore,
operators need to be aware of the hazards penetration of energized power lines poses and take positive
steps to eliminate the hazard before digging.
▪ Locate underground power lines and other utilities before digging. Utility companies will assist
with location and marking and should be contacted prior to digging.
▪ Workers must ensure that power is removed from the lines and a zero energy state has been
verified.
▪ Workers must ensure that the system is locked and tagged out.
▪ All workers must have a questioning attitude about safety and especially electrical safety.
Remember, penetration of energized underground conductors by workers can result in shock and even
death.
Warehouse Workers
Warehouse workers are exposed to a wide variety of hazards. These may include chemicals, vehicular
traffic, awkward working positions, height, and electrical shock potential. Of these the least addressed
one is electricity. Therefore workers tend to ignore electrical safety conditions because they simply
don’t recognize the hazard. This section will address some of these hazardous conditions and discuss
ways to remove them.
Electricity in warehouses is often encountered during storage and retrieval of parts that are stored at
height and involve the use of some type of lifting device such as a forklift. Warehouse workers must be
aware of the following electrical hazards and implement positive controls so that they may be avoided
▪ Use cable guards when running temporary power cords as shown in Figure 25.
▪ Verify that power lifting platforms do not raise high enough to place worker within the minimum
safe approach distance of high energy lighting and equipment conductors.
▪ Ensure that containers used to store explosive/flammable chemicals are properly grounded.
▪ Verify that the travel paths used to move stock is free from electrical outlets, controls, and power
panels that may be damaged by moving equipment.
▪ Power panels and high voltage switches and disconnects should be guarded if they are not
physically separated from the work area.
▪ All workers should know where disconnects, circuit breakers and switches are located in their area
of responsibility.
Painters
Painters are usually injured by electricity when they come in contact with energized systems through
their paint roller or their ladder. These injuries can usually be avoided simply by being more aware of
their surrounding and understanding that you must follow the basic rule when electrical energy is
present.
Painters must recognize voltage carrying conductors and stay outside the 3 ft 6 inch boundary until a deenergized
state is proven . They must be able to recognize different types of
conductors such as Cables (insulated and un-insulated), buss bars, and power carrying rails in the work place
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