Welding Safety
WY MSHA State Grant Program
Welding
 Welding joins two pieces of metal by the use of
heat, pressure, or both
 Brazing or soldering involves a filler metal which
has a lower melting point than the metal pieces
to be joined
 Metal cutting is done by heating the metal with a
flame and directing a stream of pure oxygen
along the line to be cut
Welding
 Arc Welding
 Shielded Metal Arc Welding (SMAW)
 Metal Inert Gas (MIG)
 Tungsten Inert Gas (TIG)
 Plaza Arc Welding (PAW)
 Submerged Arc Welding (SAW)
 And Many More…..more than 80 in all
Health Hazards
Gases and Fumes…
 Welding “Smoke” is a mixture of very fine particles
called fumes and gases
 Welding “Smoke” contains fumes and gases including…
 Chromium, nickel, arsenic, asbestos, manganese,
silica, beryllium, cadmium, nitrogen oxides, phosgene,
acrolein, flourine compounds, carbon monoxide, cobalt,
copper, lead, ozone, selenium, and zinc

Health Hazards…Gases & Fumes
 Generally, gases and fumes come from…
 Base material & filler material
 Coatings & paints
 Shielding gases & chemical reactions
 Process & consumables used
 Contaminants in the air
Health Hazards
 It is difficult to list all the health effects of welding
exposures because the fumes may contain so
many different substances that are known to be
harmful
 The individual components of welding “smoke”
can affect just about any part of the body,
including the lungs, heart, kidneys, & central
nervous system
Health Hazards
 Exposure to welding “smoke” may have…
 Short-term effects…
Effects happen at or very soon after exposure
 Long-term effects
Effects may happen after repeated overexposures or
an extended time after the exposure
Short-term exposures
 Exposure to zinc, magnesium, copper and
copper oxide can cause metal fume fever
 Symptoms of metal fume fevere may occur 4 to
12 hours after exposure
 Symptoms include…
 Chills, thirst, fever, muscle ache, chest soreness,
coughing, wheezing, fatigue, nausea, and
metallic taste in mouth
Short-term exposures
 Welding “smoke” can irritate the eyes, nose,
chest and respiratory tract
 Welding “smoke” can cause coughing,
wheezing, shortness of breath, bronchitis,
pulmonary edema, and pneumontis
 Welding “smoke” can cause nausea, loss of
appetite, vomiting, cramps, and slow digestion
Short-term exposures
 Exposure to cadmium can be fatal in a short time
 Ultraviolet radiation can react with oxygen and
nitrogen to form ozone and nitrogen oxides
 These gases are deadly at high concentrations
and can also cause irritation of nose and throat
and cause serious lung disease
Short-term exposures
Ultraviolet rays given off by welding can react with
hydrocarbon solvents such as…
 Trichloroethylene; 1,1,1-trichloroethane; methylene
chloride; & perchloroethylene to form phosgene gas
 Even a very small amount of phosgene gas may be
deadly

Early symptoms include dizziness, chills, and cough and
usually take 5 – 6 hours to appear
Short-term exposures
 Arc welding should never be performed within
200 feet of degreasing equipment or solvents
Long-term exposures
 Studies of welders, flame cutters, and burners
have shown that welders have an increased risk
of lung cancer…
 and…possibly cancer of the larnyx and urinary
tract
 Remember… welding “smoke” can include
cancer causing agents such as…cadmium,
nickel, beryllium, chromium, and arsenic
Long-term exposures
 Welders may experience a variety of chronic
respiratory problems, including…
 Bronchitis, asthma, pneumonia, emphysema,
pneumoconiosis, decreased lung capacity,
silicosis, and siderosis
Long-term exposures
 Other health problems…
 Heart disease, skin diseases, hearing loss,
chronic gastritis, gastroduodentis, and ulcers of
the stomach and small intestine
 Reproductive risks
Other Health Risks…
 Heat exposure…
Heat stress, heat stroke
 burns, eye injuries from hot slag, metal chips,
sparks, and hot electrodes
Other Health Risks…
 Visible light, and ultraviolet and infrared radiation
 Intense light can cause damage to retina
 Infrared radiation may damage the cornea and
result in cataracts
 Invisible UV light can cause “arc eye” or
“welders’ flash”
May include sandy or gritty eye, blurred vision,
intense pain, tearing, burning and headache
Other Health Risks…
 Permanent eye damage
 Skin burns
 Skin cancer
 Noise
Can result in stress, increased blood pressure, may
contribute to heart disease, tiredness, nervousness,
and irratability
Musculoskeletal Injuries
 Back injuries, shoulder pain, tendonitis, reduced
muscle strength, carpal tunnel syndrome, white
finger, and knee joint diseases
 Injuries may be caused by overhead work,
vibration and heavy lifting
Electrical Hazards
 Even though welding generally uses low voltage,
there is still a danger of electric shock
 Wet work areas, Cramped work spaces
 Falls, fractures and other accidents can result
from electrical exposure
 Even small shock can cause brain damage
 Death can occur from large shocks
Electrical Hazards
Always use dry gloves
 Always wear rubber soled shoes
 Always use insulating layers
 Protect yourself from surfaces that conduct electricity
 When working on electrically powered machinery, make
sure the frame is grounded
 Keep insulation on all welding equipment and
components dry and in good condition
 Don’t change electrodes with bare hands, wet gloves or
while standing on wet or ungrounded surfaces

Fire and Explosion Hazards
 Intense heat and sparks can cause fires or
explosions if in the vicinity of combustible or
flammable materials
 Welding and cutting should only be performed in
areas free of combustible materials such as
trash, wood, paper, textiles, plastics, chemicals,
and flammable dusts, liquids and gases
Fire and Explosion Hazards
Never weld or cut on containers that have held a
flammable or combustible material unless the container
is thoroughly cleaned or filled with an inert gas
 A fire inspection should be performed prior to leaving a
work area and for at least 30 minutes after the operation
is completed
 Fire extinguishers should be nearby, of proper size, type
and number for the hazards involved

Dangerous Machinery
 All machines in the area with moving parts must
be guarded to prevent worker’s contact
Hair, clothing, fingers, etc.
 When repairing machinery by brazing and
welding, power must be disconnected, locked
out, and tagged so the machinery cannot be
started up accidentently
Trips and Falls
 To prevent trips and falls…
 keep work areas clear of equipment, machines,
cables, and hoses
 Always properly maintain and use handrails
 Always use and maintain safety lines, harnesses
and lanyards
 Always make sure that scaffolds are properly
assembled and used
Welding Hazards in Confined
Space
 A work area with limited access, little or no
airflow, not intended for continuous occupation
May also have dangerous atmospheres, hazardous
configurations, or other hazards
 All employees working in or around confined
space must be trained
Welding Hazards in Confined
Space
 Never weld or cut in explosive, flammable,
combustible or other dangerous environments
 Always use all necessary Personal Protective
Equipment (PPE), including, harness and
lanyard, respiratory protection, eye protection,
etc.
 Never work in confined space without a trained
attendant
Welding Hazards in Confined
Space
 Always leave gas cylinders and welding power
sources outside the confined space…
 Only take hoses or welding leads into confined
space
 Always removed hoses and/or leads when
leaving confined space for breaks, shift or crew
changes, etc.
Welding Hazards in Confined
Space
 No worker should work in an area with less than
19.5% or more than 23.5% oxygen content
 Never ventilate with oxygen
 Use continuous mechanical ventilation and
proper respiratory protection
 All pipes, ducts, power lines, etc. that are not
necessary for the work should be
disconnected/locked out/tagged out
Compressed Gas Hazards
 Gas welding and cutting use a fuel gas and
oxygen which are stored in high pressure
cylinders
 Most fuel gases are explosive
 Pure oxygen will increase the flammability of any
combustible/flammable material
Compressed Gas Hazards
All cylinders should have caps or regulators
 Pressure regulators must be designed for gas in use
 Check all equipment and components prior to use
 Cylinders must be stored upright and secured
 Oxygen and fuel gas cylinders must be stored
separately
 Be aware of flashbacks and backfires??
 Close cylinder valves when work is completed or left
unattended during breaks, etc.

Reducing Noise Hazards
 Identify hazards and potential hazards prior to
beginning hot work
 Read the MSDS sheet to identify the hazardous
material used in welding and cutting products,
and the fumes that may be generated
 Make sure that you know what you are welding
before beginning
Cadmium exposure can be fatal in a very short time
Compressed Gas Hazards
 After a specific hazard(s) has been identified…
 you can implement appropriate control
method(s)
 You can use appropriate PPE
Engineering Controls and Work
Practices
 Substitute less hazardous materials for
hazardous materials
 Use cadmium-free silver solders
 Use asbestos- free electrodes, gloves, and hot
pads
 Use ventilation to move away or dilute hazards
 Use work area barriers to protect others working
in the same general area
Engineering Controls and Work
Practices
 Welding booths should be painted with dull
finishes so they don’t reflect UV light
 Acoustic shields between the worker and noise
sources can reduce exposures
 Noisy machinery can be totally enclosed
Engineering Controls and Work
Practices
Modify the process or follow safe work practices so that
hazards are eliminated or reduced to the minimum…
 Don’t weld on painted surfaces; use water table under
plasma arc cutting to reduce noise; Grind instead of airarcing; use sub arc; position yourself away from fumes;
remove nearby flammables/combustibles; properly
maintain equipment; proper housekeeping; use lowest
possible amperage; hold electrode perpendicular and
close to work surface
 Never weld or cut within 200 feet of degreasing
equipment or solvents

Personal Protective Equipment
(PPE)
 PPE must be used in conjunction with
engineering controls and safe work practices
Use of one does not eliminate the need for the other
 Eye protection should be used in all welding
operations
Wear face shields or helmets and goggles or safety
glasses
 Use appropriate filters on eye protection
Filter Lens Shade Numbers
 SMAW – 1/16 - 5/32 =
#10
 Gas SAW - 1/16 - 5/32 = #11 (nonferrous)
 Gas SAW – 1/16 – 5/32 = #12 (ferrous)
 SMAW – 3/16 – ¼ - = #12
 5/16 & 3/8 electrodes = #14
 Atomic Hydrogen Welding = #10 - #14
 Carbon Arc Welding CAW = #14
Filter Lens Shade Numbers
Soldering = #2
 Torch Brazing = #3 or #4
 Light cutting up to 1 inch = #3 or #4
 Medium cutting 1 inch to 6 inches = #4 or #5
 Heavy cutting over 6 inches = #4 or #6
 Light gas welding up to 1/8” = #4 or #5
 Medium gas welding 1/8” to ½ “ = #5 or #6
 Heavy Gas Welding over ½ “ = #6 or #8

Protective Clothing
Fire resistant gauntlet gloves
 Headcap
 High top hard toed shoes
 Leather apron
 Faceshield
 Flame retardant clothing
 Safety Glasses
 Safety helmet

Hearing Protectors
 Ear plugs and/or muffs should be worn during
noisy operations such as air arcing or grinding
 Most welding operations are noisy
Respirators
 Must be specific to the hazard
 Must be fitted, cleaned, stored and maintained in
accordance to regulation and manufacturers
specs
 NIOSH recommends respirators whenever a
carcinogen is present