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Welder SAFETY is
the NEW HOT
TOPIC in learn not
get burned
Welding is a joining process in
which metals, or sometimes
plastics, are heated, melted
and mixed to produce a joint
with properties similar to
those of the materials being
joined.
Safety is a critical consideration for any welding project. Arc welding is a safe
occupation when proper precautions are taken, but if safety measures are ignored,
welders face an array of hazards that can be potentially dangerous, including
electric shock, fumes and gases, fire, explosions, and more.
Welding operators face an array of hazards. To Employers should ensure that all
workers have an opportunity to comply with the following important guidelines in the
workplace:
• Read and understand manufacturer instructions for equipment
• Carefully review safety data sheets
• Follow the company's internal safety practices
• Awareness of the most common welding hazards and knowing how to avoid
them ensures a safe, productive work environment for all.
Electric Shock
Electric shock is one of the most serious and immediate risks facing a welder.
Electric shock can lead to severe injury or death, either from the shock itself or from
a fall caused by the reaction to a shock.
Electric shock occurs when welders touch two metal objects that have a voltage
between them, thereby inserting themselves into the electrical circuit. For instance,
if a worker holds a bare wire in one hand and a second bare wire with another,
electric current will pass through that wire and through the welding operator,
causing an electric shock. The higher the voltage, the higher the current, and thus
the higher the risk for the electric shock to result in injury or death.
Fumes and Gases
It's no surprise that overexposure to welding fumes and gases can be hazardous to
your health. Welding fume contains potentially harmful complex metal oxide
compounds from consumables, base metal, and the base-metal coatings, so it's
important to keep your head out of the fumes and use enough ventilation and/or
exhaust to control your exposure to substances in the fume, depending on the type
of rod and base metal being used. The specific potential health effects related to the
welding consumable product being used can be found in the Health Hazard Data
section of the safety data sheet that is available from your employer or the
consumable manufacturer.
Welding areas require adequate ventilation and local exhaust to keep fumes and
gases from the breathing zone and the general area. In most situations, employers
will provide a ventilation system--such as a fan and an exhaust system or fixed or
removable exhaust hoods--to remove fumes and gases from the work area.
There are three main components needed to create a weld. These are:
•A heat source such as an electric arc, a flame, pressure, or friction. The most
common heat source is an electric arc. An arc is the physical gap between the end
of the electrode and the base metal. The physical gap causes heat due to resistance
of current flow and arc rays. The arc melts the metals to create the joint.
•Shielding, which is the use of gas, or another substance to protect the weld from air
as the weld is being formed. Oxygen from the air makes welds brittle and porous.
•Filler material, which is the material used to join to the two pieces together.
Other processes that join metals together include:
•Brazing is the joining of metals with a filler metal having a melting point above
450°C (842°F), but below the melting point of base metals.
•Soldering is the joining of metals using a filler metal with a melting point below
450°C (842°F). The joined metals can be different metals. The "filler"metals
commonly used are lead-tin alloys.
Metals can also be cut or separated by a flame or an electric arc, or removed by
"gouging" with an electric arc.
What measures can you use for skin protection from welding radiation?
•Wear tightly woven work-weight fabrics to keep UV radiation from reaching your
skin.
•Button up your shirt to protect the skin on the throat and neck.
•Wear long sleeves and pant legs.
•Cover your head with a fabric cap to protect the scalp from UV radiation.
•Protect the back of your head by using a hood.
•Protect your face from UV radiation by wearing a tight-fitting, opaque welder's
helmet.
•Make sure that all fabric garments are resistant to spark, heat and flame. Keep the
fabrics clean and free of combustible materials that could be ignited by a spark.
DO
•Wear clothing made from heavyweight, tightly woven, 100% wool or cotton to
protect from UV radiation, hot metal, sparks and open flames. Flame retardant
treatments become less effective with repeated laundering.
•Keep clothing clean and free of oils, greases and combustible contaminants.
•Wear long-sleeved shirts with buttoned cuffs and a collar to protect the neck. Dark
colours prevent light reflection.
•Tape shirt pockets closed to avoid collecting sparks or hot metal or keep them
covered with flaps.
•Pant legs must not have cuffs and must cover the tops of the boots. Cuffs can
collect sparks.
•Repair all frayed edges, tears or holes in clothing.
•Wear high top boots fully laced to prevent sparks from entering into the boots.
•Use fire-resistant boot protectors or spats strapped around the pant legs and boot
tops, to prevent sparks from bouncing in the top of the boots.
•Remove all ignition sources such as matches and butane lighters from pockets. Hot
welding sparks may light the matches or ignite leaking lighter fuel.
•Wear gauntlet-type cuff leather gloves or protective sleeves of similar material, to
protect wrists and forearms. Leather is a good electrical insulator if kept dry.
•Direct any spark spray away from your clothing.
•Wear leather aprons to protect your chest and lap from sparks when standing or
sitting.
•Wear layers of clothing. To prevent sweating, avoid overdressing in cold weather.
Sweaty clothes cause rapid heat loss. Leather welding jackets are not very
breathable and can make you sweat if you are overdressed.
•Wear a fire-resistant skull cap or balaclava hood under your helmet to protect your
head from burns and UV radiation.
•Wear a welder's face shield to protect your face from UV radiation and flying
particles.
DO NOT
•Do not wear rings or other jewellery.
•Do not wear clothing made from synthetic or synthetic blends. The synthetic fabric
can burn vigorously, melt and produce bad skin burns.
Have you covered with staff during safety meeting items like but not limited too!
• Fumes and Gases
• Radiation
• Noise
• Chromium and Nickel in Welding Fume
• Electrical Hazards
• Fire and Explosion Prevention
• Burn Protection
• Mechanical Hazards
• Tripping and Falling
• Falling Objects
• Confined Spaces
• Contact Lens Wear
• Ergonomics in the Welding Environment
• Graphic Symbols for Precautionary Labels
• Style Guidelines for Safety and Health Documents
• Pacemakers and Welding
• Electric and Magnetic Fields (EMF)
• Lockout/Tagout
• Laser Welding and Cutting Safety
• Thermal Spraying Safety
• Resistance Spot Welding
• Cadmium Exposure from Welding and Allied Processes
• Fluxes for Arc Welding and Brazing: Safe Handling and Use
• Metal Fume Fever
• Arc Viewing Distance
• Thoriated Tungsten Electrodes
• Oxyfuel Safety: Check Valves and Flashback Arrestors
• Grounding of Portable and Vehicle Mounted Welding Generators
• Cylinders: Safe Storage, Handling, and Use
• Eye and Face Protection for Welding and Cutting Operations
• Personal Protective Equipment (PPE) for Welding and Cutting
• Coated Steels: Welding and Cutting Safety Concerns
• Ventilation for Welding and Cutting
• Selecting Gloves for Welding and Cutting
• Respiratory Protection Basics for Welding Operations
• Asbestos Hazards Encountered in the Welding and Cutting Environment
• Combustible Dust Hazards in the Welding and Cutting Environment
Hazards of Electric Shock
Q: Under what circumstances can you receive an electric shock?
A: You receive an electric shock when you touch two metal objects that have a
voltage between them.
Q: At what voltage can you be injured by an electric shock?
A: 120 volts is a common voltage which is found in every home in North America. 50
volts or less may be enough to injure or kill depending upon the conditions.
Q: Which is more hazardous: AC (Alternating Current) or DC (Direct Current) current?
A: As a general rule, Alternating Current (AC) is more hazardous than Direct Current
(DC).
Q: What voltages are used in the arc welding process?
A: Arc welding involves open circuit (when not welding) voltages which are typically
from as low as 20 volts to as high as 100 volts.
Q: What voltages are normally found inside the case of an arc welder?
A: The voltage inside welding equipment is commonly much higher: from 120 volts to
575 volts or more.
Primary Electric Shock
Q: Why is the primary voltage shock more hazardous than the secondary shock?
A: The primary voltage shock - at 115 volts to as high as 600 volts - is very hazardous
because it is much greater voltage than the welder secondary (or welding) voltage.
Q: When can you receive a primary voltage electric shock?
A: You can receive a shock from the primary (input) voltage if you: touch a lead or
other electrically "hot" component inside the welder while you have your body or
hand on the welder case or other grounded metal with the power to the welder "on."
Q: What must you do to turn off the electric power inside the welder case?
A: To turn the power inside the welder "off", the input power cord must be unplugged
or the power disconnect switch turned off.
Q: What is the purpose for grounding the case of an arc welder?
A: The case must be grounded so that if a problem develops inside the welder a fuse
will blow, disconnecting the power and letting you know that repair is required.
Q: How can you identify the grounding lead in the input power cable?
A: The input power grounding lead has green insulation or may have no insulation at
all.
Q: What is the difference between the work lead and the grounding lead?
A: The Green Grounding Lead used to connect the welder to earth ground is not the
same as the Work Cable (sometimes called the "Welding Ground Cable") which is
part of the arc welding circuit and only carries welding current. The Work Cable does
not Ground the welder case.
Secondary Electric Shock
Q: What must occur for you to get a secondary voltage electric shock?
A: A secondary voltage electric shock occurs when you touch a part of the welding
or electrode circuit - perhaps a bare spot on the electrode cable at the same time
another part of your body is touching the metal upon which you're welding (work). To
receive a shock, your body must touch both sides of the welding circuit, electrode
and work (or welding ground) at the same time when the welding output is on.
Q: When is the voltage at the electrode the highest?
A: The voltage at the electrode is highest when you are not welding (open circuit
voltage).
Safe Work Practices
Q: When is a stick electrode "electrically hot"?
A: A stick electrode is always "electrically hot" when the welder is on.
Q: How do you protect yourself from electric shock when welding?
A: Insulate your body from the metal you are welding. Don not rest you body, arms, or
legs on the work piece (the metal being welded), especially if your clothing is wet or
bare skin is exposed (and it should not be if you are dressed properly). Use plywood,
rubber mats or some other dry insulation to stand or lie upon. Wear dry gloves in
good condition when welding. Do not touch the electrode or metal parts of the
electrode holder with skin or wet clothing.
Electrically Hazardous Areas
Q: Under what conditions is arc welding electrically hazardous?
A: A situation can be electrically hazardous if welding must be performed under
electrically hazardous conditions (in damp locations or while wearing wet clothing,
on metal structures such as floors, gratings or scaffolds, when in cramped positions
such as sitting, kneeling or lying, or if there is a high risk of unavoidable or
accidental contact with the work piece or ground).
Q: What type of welding equipment is best suited for arc welding under electrically
hazardous conditions?
A: Semiautomatic DC Constant Voltage welder, DC Manual (stick) welder or AC
welder with Reduced Voltage Control.
Q: What should you do if you receive an electric shock?
A: If you experience an electric shock under any circumstances, think of it as a
warning. Check your equipment, work habits and work area to see what is wrong
before continuing to weld. See your physician immediately.
Q: What should you do if you think something is wrong with your welder?
A: If you think something is wrong, disconnect input power from the welder and
report the problem to your supervisor or to a Qualified Electrician. Do not use the
welder again until it has been checked.
Health Effects: Fumes
Q: What compounds are found in common welding fume?
A: The most common compounds in arc welding fume mild steel are iron, manganese
and silicon although other compounds in the electrode or on the base metal may be
in the welding fume.
Q: What types of electrode products are likely to have chromium or nickel in the
welding fume?
A: Fumes from the use of stainless steel and hardfacing products contain chromium
or nickel.
Q: What are the potential health effects that may result from long-term
overexposure to chromium or nickel?
A: Asthma has been reported and some forms of these metals are known or
suspected to cause lung cancer in processes other than welding. Therefore, it is
recommended that precautions be taken to keep exposures as low as possible.
Q: What are the potential health effects that may result from sustained
overexposure to manganese?
A: Manganese overexposure may affect the central nervous system, resulting in poor
coordination, difficulty in speaking and tremor of arms or legs. This condition is
considered irreversible.
Q: What are the long-term health effects associated with exposure to welding fume?
A: Check an LH70 SDS sheet, including comments on siderosis and irritation of nose
and throat.
Q: What are the potential health effects that may result from overexposure to zinc?
A: Overexposure to zinc may cause fume fever with symptoms similar to the common
flu.
Q: What is a common source of zinc in welding fume?
A: Zinc in welding fume usually comes from welding on galvanized steel.
Warnings
Q: Where can you find safety instructions regarding welding products that you use?
A: Each welding power source and container of consumable product has a warning
label which contains specific safety instructions regarding the arc welding product
you have chosen to use.
Q: What information is contained on a material safety data sheet (SDS)?
A: An SDS contains additional information including a summary of the Hazardous
Materials used to manufacture the product, a summary of Fire and Explosion Hazard
Data, Health Hazard Data and Reactivity Data, and information on the precautions to
observe for the Safe Handling and Use of the product.
Q: Since fumes and gases can be dangerous to your health, what three steps should
you take to protect yourself?
A: 1) Keep fumes and gases from your breathing zone and general area 2) Keep your
head out of the fumes 3) Use enough ventilation or exhaust at the arc, or both, to
keep fumes and gases from your breathing zone and general area.
Q: What additional precautions should be followed for products that require special
ventilation?
A: If special ventilation products are used indoors, use local exhaust. If special
ventilation products are used outdoors, a respirator may be required.
Q: What types of products generally require special ventilation?
A: Hardfacing and stainless products.
Health Effects: Gases
Q: What are the potential health hazards related to shielding gases used in arc
welding?
A: Most of the shielding gases (argon, helium and carbon dioxide) are non-toxic, but
they can displace oxygen in your breathing air causing dizziness, unconsciousness
and possible death. Carbon monoxide can also be present and may pose a hazard if
levels are excessive.
Adequate Ventilation
Q: What is the one of the most basic safety precautions that a welder can take to
protect themselves from overexposure to welding fume?
A: Keep your head out of the fume plume!
Q: Where is the concentration of fumes and gases greatest?
A: Concentration of fumes and gases is greatest in the plume.
Q: How can you keep fumes and gases away from your breathing zone?
A: Keep fumes and gases from your breathing zone and general area using natural
ventilation, mechanical ventilation, fixed or moveable exhaust hoods, or local
exhaust at the arc.
Q: What precautions must be taken if adequate ventilation cannot be provided?
A: It may be necessary to wear an NIOSH approved respirator if adequate ventilation
cannot be provided.
Q: Does OH&S require engineering or workplace controls be installed before
respirators can be used?
A: OH&S requires that engineering and workplace controls be installed first and if
the controls alone do not keep exposures below applicable limits, use respirators.
Q: How can a welder determine if there is adequate ventilation?
A: As a practical rule of thumb for welders, for many mild steel electrodes, if the
welder is comfortable and the air is visibly clear, the welder has adequate
ventilation.
Q: What method is used to accurately measure a welder's exposure to welding
fume?
A: A welder's exposure can only be determined by having a qualified professional
take a sample of the welder's breathing air during the workday.
Q: When is it most important to measure a welder's exposure to welding fume?
A: Measuring a welder‘s exposure to welding fume is essential if you are welding
with stainless, hardfacing or other special ventilation products (see the product
label).
Q: What precautions should be taken when welding a base metal which is plated or
painted?
A: If the base metal cannot be cleaned before welding, the composition of the
coating should be evaluated.
Q: What should you do if you feel overexposed to welding fume?
A: Stop welding and get some fresh air immediately. If you continue to feel the
symptoms, see your doctor. Notify your supervisor and co-workers so the situation
can be corrected and other workers are aware of and can avoid the hazard. Be sure
you are following safe practices, as stated upon the consumable labeling and SDS,
and improve the ventilation in your area. Do not continue welding until the situation
has been corrected.
Q: What does adequate ventilation mean?
A: Your work area has adequate ventilation when there is enough ventilation and
exhaust to control worker exposure to the hazardous materials in the welding fumes
and gases (so the applicable exposure limit for those materials is not exceeded).
Q: What are the most commonly used exposure limits?
A: The two most common U.S. exposure limits are established by OH&S in the form
of permissible exposure limits or PEL and by the ACGIH in the form of Threshold
Limit Values or TLV.
Q: Where can you find the applicable limits for the PEL and TLV for substances in
welding fume?
A: The PEL and TLV are listed on the first page of the SDS for compounds in each
electrode or flux.
Evaluating the Welding Environment
Q: What steps can you, the welder, take to identify hazardous substances?
A: There are also steps that you should take to identify hazardous substances in your
welding environment. Read the product label to review the warnings, safety
precautions and to determine if special ventilation is needed. Obtain and review the
material safety data sheet (SDS) for the electrode which your employer or supervisor
has posted in the work place or that you find inside the electrode or flux container.
You should review the complete SDS to determine specifically what compounds you
may be exposed to when using the product.
Q: Where can the welder find information about materials in the base metal or any
coating on the base metal?
A: Obtain a copy of the supplier's SDS for the base metal being welded, as this
should be reviewed as well.
Welding Fume Control
Q: What is natural ventilation?
A: Natural ventilation is the movement of air through the workplace caused by
natural forces. Outside, this is usually the wind. Inside, this may be the flow of air
through open windows and doors.
Q: What is mechanical ventilation?
A: Mechanical ventilation is the movement of air through the workplace caused by an
electrical device such as a portable fan or permanently mounted fan in the ceiling or
wall.
Q: What is local exhaust?
A: Local exhaust is a mechanical device used to capture welding fume at or near the
arc and remove contaminants from the air.
Q: What factors need to be considered when determining the exhaust requirements
for your application?
A: The ventilation or exhaust needed for your application depends upon factors such
as:
Workspace volume
Workspace configuration
Number of welders
Welding process and current
Consumables used (mild steel, hardfacing, stainless, etc.)
Allowable levels (TLV, PEL, etc.)
Material welded (including paint or plating)
Natural airflow
Q: Name several types of local exhaust that can be used to control exposure to
welding fume?
A: Local exhaust of welding fumes can be provided by any of the following:
adjustable "elephant trunk" exhaust systems, fume extraction guns or fixed
enclosures, or booths with exhaust hoods.
Q: Which system is more effective and economical: general ventilation or local
exhaust systems?
A: Local exhaust systems are more effective and economical to operate than a
general ventilation system, particularly in the winter, because they require less
replacement air to be brought into the room and heated.
Q: What is the minimum air velocity (speed) required near the welding arc?
A: Minimum required air velocity at the welding arc is 100 fpm.
Q: When should an employee's exposure to welding fume be obtained?
A: Exposure should be checked when new ventilation equipment is installed, when
the process is modified or when the welder feels uncomfortable. Periodically,
exposure should be re-checked to be sure it is still working properly and is adequate.
Special Ventilation Reminder
Q: What must be done to insure that there is adequate ventilation when welding with
electrodes that require special ventilation (such as stainless or hardfacing, or other
products which require special ventilation - see instructions on container or SDS) or
on lead or cadmium plated steel and other metals or coatings like galvanized steel,
which produce hazardous fumes?
A: Keep exposure as low as possible and below exposure limit values (PEL and TLV)
for materials in the fume using local exhaust.
Q: When should a respirator be used?
A: In confined spaces or in some circumstances, for example outdoors, a respirator
may be required if exposure cannot be controlled to the PEL or TLV (see SDS).
Q: When does OH&S consider natural ventilation sufficient?
A: According to OH&S regulations, when welding and cutting (mild steels), natural
ventilation is usually considered sufficient to meet requirements, provided that:
The room or welding area contains at least 10,000 cubic feet (about 22' x 22' x 22')
for each welder
The ceiling height is not less than 16 feet
Cross ventilation is not blocked by partitions, equipment or other structural barriers
Welding is not done in a confined space
Regardless of the whether the ventilation meets these requirements, the welder's
exposure must be controlled to below the PEL or TLV (if applicable) exposure limit to
be adequate.
Fire Hazards
Q: What aspects of arc welding create the hazard of fire and explosion?
A: The danger of fire results from the effects of this intense heat upon your work and
in the form of sparks and molten metals created by the arc.
Q: What should you do prior to welding to avoid the hazard of fire and explosion?
A: Before you start welding, inspect the work area in which you will be welding. Look
for flammable substances that could ignite when heated. If you are not sure whether
or not a substance in the work area is flammable, no welding or cutting should take
place until a responsible person has inspected the area and given approval for the
work or the material has been removed or protected.
Q: What can be used to put out a fire if fire extinguishers are not available?
A: If there are no fire extinguishers in the area, make sure that you have access to
fire hoses with available water pressure, sand buckets, fire-resistant blankets, or
other fire-fighting equipment. Remember, always locate the nearest fire exit in case
there is a fire and you have to leave the area.
Q: When do you need a fire watcher?
A: If you are welding within 35 feet or so of flammable materials, you should have a
fire watcher to see where your sparks are flying and to grab an extinguisher or sound
the alarm if needed. You and the fire watcher should wait for at least one half hour
after all welding is finished to find and put out any smoldering fires that may have
resulted from your welding.
Q: What can you do to prevent fire or explosion if you need to weld on near
flammable materials which cannot be moved away from the arc?
A: If there are flammable materials, including fuel or hydraulic lines, in your work
area and you can‘t move your work or the flammable material, put a fire-resistant
shield such as a piece of sheet metal or fire resistant blanket in place over the
material.
Q: How can dust pose a fire hazard?
A: Particular care must be taken when welding or cutting in dusty locations. Under
some conditions, fine dust particles may readily burn and without warning result in a
flash fire or even an explosion when exposed to the welding arc or even sparks.
Closed Containers
Q: What special precautions need to be taken when welding on containers or piping
that may contain flammable materials?
A: Welding on or around containers and piping that may have flammable materials
should only be handled by experienced welders who review and follow the safety
practices recommended in the American Welding Society document F4.1:
"Recommended Safe Practices for the Preparation for Welding and Cutting of
Containers and Piping Which Had Held Hazardous Substances." Special precautions
which must be taken when welding upon containers may include filling the container
with an inert gas or water.
Q: Who can perform arc welding on closed containers or piping that may contain
flammable materials?
A: Welding upon containers or piping should only be performed by qualified welders.
Q: What potential fire or explosion hazard should you look for when welding on or
around equipment or vehicles that use fuel or hydraulic oil?
A: Do not forget to look for and protect any fuel or hydraulic lines near the arc. Lines
which contain a flammable liquid under pressure are particularly dangerous and
should be avoided when welding.
Q: What should you do if you notice that a fire has started near where you are
working?
A: Do not panic. If the fire is very small, you may be able to use the equipment you
have to put out the fire however, if the fire is too large, call the fire department.
Always sound the fire alarm to warn other workers nearby and shut off your welder if
there is a fire. Then leave the area as quickly as possible.
Q: Where should the spray from the fire extinguisher be directed?
A: The spray from any extinguisher should be directed at the base of the fire on the
material which is burning, not on the flames above the material.
Q: What type of program should your company have to help to protect your facility
from the risk of fire or explosion?
A: Your company may have a specific hot work permit program that may require
additional precautions and procedures are followed. Consult your safety coordinator
or your supervisor to the appropriate training and certification.
Shop Warning Labels
Q: What is a warning label?
A: A warning label is a label that contains information about the safe use of a
product that you need to know to use the product safely. You should read a warning
label prior to first using a product.
Q: On what types of welding machines can you find warning labels?
A: You can find warning labels on the following types of arc welding and cutting
products: arc welding equipment, including arc welders and wire feeders and arc
welding electrode and flux products.
Q: What types of hazards and reference information does a typical warning label
review?
A: A warning label covers the basic hazards encountered in arc welding such as
exposure to arc welding, fumes and gases, electric shock, arc rays and fire and
explosion. It also instructs the welder to read and follow the manufacturer's
instructions and refers the welder to the OH&S Regulations and the American
National Standard regarding Arc Welding and Cutting Safety (ANSI Z49.1).
Q: Why is it a good idea to review warnings periodically?
A: Warnings on electrode and flux products are updated occasionally so it is a good
idea to review them again periodically to be sure you have the information you need
to use the product safely. The warnings also vary from product to product so when
you change the product you are using you should review the warning on the new
product when you begin to use it.
Q: What is the purpose of a special ventilation note?
A: Special ventilation notes inform the user that a particular substance in the
electrode is present in sufficient amounts and that additional ventilation is needed to
properly control fume exposure. Special ventilation notes commonly relate to
manganese and chromium in the welding fume, however other substances may also
require such notes. Special attention to ventilation is important when welding with
products having such notes.
SDS
Q: Why were GHS Safety Data Sheets (SDS) developed?
A: SDS were developed to inform millions of North American workers of the potential
hazards of handling and working with thousands of chemicals and other substances.
Q: Does each consumable product have an SDS?
A: An SDS is available for all welding electrodes and fluxes and may be obtained
from welding distributors or the manufacturers.
Q: What system provides information about the amount of chemical in welding fume
that a welder may be repeatedly exposed to?
A: Both the TLV and PEL relate to the measured weight (in milligrams) of welding
fume per volume (in cubic meters) to which you may be repeatedly exposed without
adverse health effects.
Q: What are typical symptoms of short-term overexposure to welding fumes?
A: Short-term overexposure, for instance, can cause dizziness, nausea or irritation of
the nose, throat and eyes. Long-term overexposure to welding fumes can lead to
siderosis (iron deposits in the lungs) which is not normally harmful but in large
amounts may affect breathing generally.
Q: What medical procedure should be followed if an accident occurs?
A: Emergency and First Aid procedures are very important but provide only initial
guidance. Always call a doctor or local emergency squads as quickly as possible
after an accident occurs. Review the emergency and first aid procedure section in
the SDS to be sure you or at least one of your co-workers can give the first aid
treatment suggested.
Q: What type of information is included in the reactivity data portion of an SDS?
A: This section describes the effects upon the material when it reacts with another
material. In the case of welding electrodes, the reaction is the welding process and
the result, other than the actual weld, is that some of the electrode ingredients and
other nearby materials (oils, coating, air, etc.) react in the intense heat to produce
welding fumes and gases. Since the reactions that take place are complicated and
vary depending upon the situation, the fumes and gases also vary.
Q: What is the purpose of the Control Measure and Precautions for Handling and Use
sections of the SDS?
A: The purpose of this section is to provide information about how exposure to the
material, including welding fume, can be controlled. This section also provides
information about how the material can be handled safely.
Trailer Safety
Q: What is the most important consideration in selecting a trailer for your
application?
A: Trailer capacity must be adequate for the payload.
Q: Where can you find the rated capacity for a trailer?
A: Check the manufacturer's specifications and the capacity plate on the trailer.
Q: What is the most important consideration in selecting a tow vehicle?
A: Tow vehicle and hitch capacity. Check capacity and serviceability of the tow
vehicle and hitch.
Q: What is generally recommended minimum tongue weight for a trailer?
A: Always maintain a minimum tongue weight of approximately 8% of total trailer
plus payload weight.
Q: How and when should safety chains be connected when towing a trailer?
A: Safety chains should always be crossed under the tongue of the trailer and
connected to the eyes of the hitch. Install safety chains on trailer before towing the
trailer. Be sure the safety chains and emergency brake cable are in place and
properly connected.
Q: What should be done to be sure that the trailer and tow vehicles tires are
prepared for towing?
A: Check the tires and tire pressure. Inspect all tires for damage or wear - this
includes the tow vehicle tires. Tire pressures should be set to the trailer or vehicle
manufacturer's recommended pressure and not greater than the maximum pressure
on the tire.
Q: What should be checked about the wheels on the trailer and tow vehicle before
towing?
A: Check to be sure all lug nuts are tight. Be sure bearings are serviced and have
grease. Bearing failure can cause a wheel and tire to separate from the trailer.
Q: What about the trailer lights should be checked before towing?
A: Check to see that the trailer wiring is properly hooked up and working. Do not tow
trailer after dark without lights.
Q: What can be done to avoid fuel leakage with engine driven equipment is towed?
A: Most engine driven equipment has a shutoff in the fuel line or at the tank. Always
shut off the fuel when trailoring to prevent fuel leakage.
Q: What should you do if a trailer begins to sway or become difficult to control?
A: If the trailer is not stable or if a problem develops or something does not feel right
do not ignore it. Do not continue to tow the trailer if you think there is a problem.
Immediately slow down and pull the trailer off the road in a safe location and
recheck the trailer and tow vehicle. Fix the problem off the road.
Welding in Confined Spaces
Q: How does welding in a confined space affect the safety precautions that should
be taken?
A: When arc welding in a confined area, such as a boiler, tank, ship hold, or similar
confined, enclosed or restricted space, bear in mind that all the hazards associated
with normal arc welding are amplified. Therefore, special precautions must always
be taken.
Q: What is the definition of a confined space?
A: The definition of a confined space, according to OH&S is: 1) it is large enough and
so configured that an employee can bodily enter and perform assigned work 2) has
limited or restricted means for entry or exit (for example: bins, silos, tanks, vessels,
hoppers, vaults and pits) and 3) is not designed for continuous human occupancy.
Q: What hazards are more of concern when welding in a confined space?
A: In a confined space there is a greater danger that flammable gases may be
present that could cause an explosion. Also, the walls of a metal enclosure or space
can become electrically energized and become part of the circuit, presenting an
electrical hazard to the welder or other entrants. Fumes from welding or other hot
work can accumulate more rapidly and concentrate to dangerous levels in enclosed
or confined spaces. Fumes generated from the work itself or the gases used for
welding and hot work can also have the potential to displace or force out breathable
air, while also potentially consuming and reducing oxygen concentrations to below
safe levels.
Q: What should be done to evaluate the atmosphere inside a confined space prior to
entering?
A: The following atmospheric hazards must be assessed for any confined space prior
to entry: 1) test for safe oxygen levels 2) test for combustible gases and vapors and
3) test for toxic gases and vapors.
Q: What precautions must employers take if they have a confined space in the
workplace?
A: Employers must have a written confined space entry program that includes
specialized training for employees that enter confined spaces, serve as attendants
to those entering and for those who supervise confined space entries. They must
also have a written entry permit process that includes a hazard assessment and
specific entry procedures that employees must follow in order to safely complete
assigned work.
EMF, Pacemakers and Defibrillators
Q: What causes electric and magnetic fields (EMF)?
A: Electric current flowing through any conductor causes localized Electric and
Magnetic Fields (EMF). For example, when you are welding the welding current
flowing through your arc welder and welding cables creates an EMF field near the
welder and the welding cables.
Q: What precautions should be taken by welders who have pacemakers or
defibrillators?
A: Since EMF fields may interfere with some pacemakers, welders having a
pacemaker (or defibrillator) should consult their physician before welding.
Q: What is known about the health effects of exposure to EMF fields in welding?
A: Exposure to EMF fields in welding may have other health effects which are now
not known. It is prudent for you to use good practice when arc welding to minimize
your exposure to EMF.
Q: What procedures should be followed by the welder to reduce exposure to EMF?
A: All welders should use the following procedures in order to minimize exposure to
EMF fields from the welding circuit: route the electrode and work cables together.
Secure them with tape or tie wraps when possible. If the cables are routed together,
the EMF field at that point is reduced. Some cables even include electrode and work
conductors inside one cable which may be a convenient way to reduce EMF
exposure.
Q: Why should you never coil the electrode or work cables around your body?
A: Coiling the cables around your body increases your exposure to EMF.
Q: How should cable be positioned relative to your body when welding?
A: Do not place your body between the electrode and work cables. If the electrode
cable is on your right side, the work cable should also be on your right side. There is
an EMF field at and between each cable.
Q: What is the recommended point at which the work cable should be connected to
work?
A: Connect the work cable to the work piece as close as possible to the area being
welded.
Q: Why is it not good practice to weld next to the welding power source?
A: Welding next to the welding power source increases your exposure the EMF due
to the field located at the welder.
Q: What arc welding processes minimize EMF exposure and may be particularly
suitable for welders that have a pacemaker or defibrillator and for whom welding has
been approved by their physician?
A: You may further minimize EMF exposure by using arc welding processes such as
TIG or by welding at the lowest DC output settings acceptable for your welding
application. This is particularly important if you have a pacemaker or defibrillator.
Q: What precautions should be taken prior to welding by any welder that has a
pacemaker or defibrillator?
A: If you have a pacemaker or defibrillator and wish to continue to weld you must
talk to your physician and follow the advice that he gives.
Clothing
Q: What is the most common injury to a welder?
A: Burns are the most common injury to welders due to sparks landing on the skin.
Welding arcs are very intense and can cause burns to skin and eyes with just a few
minutes of exposure.
Q: What protective clothing is needed in arc welding?
A: Protective clothing needed for welding includes general fire resistant clothing,
safety glasses, shoes, gloves, helmet and leathers.
Q: Can oxy-fuel tinted goggles be used to protect your eyes while arc welding?
A: No, oxy-fuel goggles do not protect your eyes from the intense ultraviolet radiation
(UV) produced by the welding arc. A welding helmet with the proper shaded lens
must be used whenever welding.
Q: What types of fabric are recommended for clothing worn when arc welding?
A: Because of its durability and resistance to fire, wool clothing is suggested over
synthetics. Synthetics should never be worn because it melts when exposed to
extreme heat. Cotton can be worn if it is specially treated for fire retardation.
Q: What are steps that you can take to prevent hot sparks from being trapped in
your clothing?
A: Avoid rolling up your sleeves or pant cuffs, because sparks or hot metal could
deposit in the folds. Also, wear your pants outside your work boots, not tucked in, to
keep particles from falling into your boots.
Safety Glasses
Q: Is it necessary to wear safety glasses if you are already wearing a welding
helmet?
A: Even when wearing a helmet, Z87.1 approved safety glasses with side shields, or
goggles, should always be worn to protect your eyes from flying particles.
Shoes
Q: What types of footwear are recommended for welders?
A: Leather boots with six- to eight-inch ankle coverage are the best foot protection.
Where heavy work is done, safety-toe protection boots should be worn. Metatarsal
guards over the shoe laces can protect them from falling objects and sparks.
Gloves
Q: What types of gloves are suitable for protecting your hands while welding?
A: Heavy, flame-resistant gloves (from materials such as leather) should always be
worn to protect your hands and wrists from burns, cuts and scratches. As long as
they are dry and in good condition, they will offer some insulation against electric
shock.
Helmets and Arc Rays
Q: What are the two forms of radiation given off by the welding arc?
A: The two types of radiation are Infrared (IR) and Ultraviolet (UV) radiation. IR
radiation can cause retinal burning and cataracts. IR can usually be felt as heat. UV
radiation, which cannot be felt, can cause an eye burn known as "Welder‘s Flash."
Q: How can exposure to IR and UV radiation injure your eyes?
A: It is essential that your eyes are protected from radiation exposure. IR radiation
can cause retinal burning and cataracts. IR can usually be felt as heat. UV radiation,
which cannot be felt, can cause an eye burn known as "Welder's Flash." This
condition may not be apparent until several hours after exposure. It can cause
extreme discomfort and can result in swelling, fluid excretion and temporary
blindness. Normally, "Welder's Flash" is temporary, but repeated or prolonged
exposure can lead to permanent injury of the eyes.
Q: Is it safe to weld without a welding helmet for a brief period of time, such as
during tack welding?
A: Even brief exposure to UV rays can result in a burn to the eyes known as "Welders
Flash" which may not be evident until several hours after exposure. It causes
extreme discomfort and can result in swelling, fluid excretion from the eyes and
even temporary blindness. Normally, this condition is temporary, but repeated
overexposure to UV radiation can result in permanent eye damage.
Q: How do you select the proper filter lens for your welding helmet?
A: The general rule of thumb is to choose a filter too dark to see the arc and then
move to the next lighter setting without dropping to below the minimum
recommended rating.
Q: How can you tell that you are being overexposed to radiation from the welding
arc?
A: Infrared (IR) radiation cannot be seen but is felt as heat. And there is no way to
sense if you are being overexposed to Ultraviolet (UV) radiation – so just do not take
any chances and always wear eye and face protection with the proper protective
shading.
Q: How can overexposure to the UV radiation from the welding arc injure you?
A: UV radiation can also burn exposed skin. This process is similar to getting
sunburn from overexposure to the sun. Long exposure to arc rays without protection
can lead to second and third degree skin buns. Repeated overexposure to ultraviolet
radiation is a known cause of skin cancer.
Q: Is it safe to wear contact lenses while arc welding?
A: Welders should be able to wear contact lenses safely in most situations – provided
they wear appropriate industrial eye wear and use the protection we've already
discussed with respect to protection against arc rays. Anyone wearing contacts on
the job should consult with their company medical staff and their own
ophthalmologist.
Noise and Hearing Protection
Q: How can you protect your hearing when arc welding?
A: Earplugs and earmuffs keep metal sparks and airborne particles from entering
your ear canal and protect your hearing from the effects of excessive noise.
Q: How do you know when the noise level to which you are exposed is potentially
hazardous?
A: Levels of noise over 85 decibels, averaged over an eight-hour workday, are
potentially hazardous to your hearing. When noise levels are painful or are loud
enough to interfere with your ability to hear others speaking at a normal
conversational volume this is an indication that levels are potentially hazardous.
Q: How does exposure to high noise levels damage your hearing?
A: The length and number of times you are exposed to high levels of noise
determines the extent of the damage to your hearing. High noise levels cause
damage to the ear drum and other sensitive parts of your inner ear.
Q: In addition to wearing hearing protection, what measures can you take to protect
yourself from high noise levels?
A: If it is not possible to reduce the level of noise at the source by moving either
yourself or the equipment, or by using sound barriers, then you should wear adequate
ear protection.