Welding Safety - Hellman & Associates
Download
Report
Transcript Welding Safety - Hellman & Associates
Welding Safety
Cummins Southern Plains, Ltd.
Welding Safety
Health Hazards
Electrical Hazards
Fire & Explosion Hazards
Trips and Falls
Compressed Gas Hazards
Identifying Hazards
Reducing Hazards
Basic Safety Rules
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 fever 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 pneumonitis
Welding “smoke” can cause
nausea, loss of appetite,
vomiting, cramps, and slow
digestion
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
Other Health Risks…
Heat exposure…
Heat stress, heat stroke
Burns, eye injuries from hot slag, metal chips, sparks,
and hot electrodes
Shirts
keep collar and sleeves buttoned to keep out sparks and
remove pockets or tape them shut
Pants
no cuffs and come over shoe tops
DANGER
Other Health Risks…
DO NOT
WATCH
ARC
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
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 Prevention and Protection
Cutting
torch temperatures can exceed
5000 degrees F
Suitable fire extinguishers shall be
maintained in a state of readiness
Fire Watchers are required whenever
welding and cutting is performed in
locations where other than a minor fire
might develop
Fire Prevention and Protection
Fire
Watchers are also required when:
Appreciable combustible materials, in
building construction or contents, are
closer than 35 feet to the point of
operation
Appreciable combustible materials more
than 35 feet away but are easily ignited by
sparks
A fire watch shall be maintained for at
least one half hour after the completion of
welding or cutting operations
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
Case Study
Arc welder dies in explosion while using an old barrel
as a worktable
A 38-year-old male arc welder died as a result of an
explosion at a construction company.
The victim was arc welding some brackets on the back of the
truck.
He was apparently welding with a wire welder and used a
metal 55-gal barrel as a worktable while welding.
Apparently the heat or sparks from the welding ignited
residual vapors and/or material in the barrel, causing it to
explode.
The explosion knocked the victim down, and started a fire in
the immediate area.
Case Study
Recommendations
Ensure welders are suitably
trained in safe operation of
equipment and process.
Ensure that welding should not
be performed on or near used
drums, until they have been
thoroughly cleaned.
Develop, implement, and enforce
a written safety program,
including HOT WORK.
Designate a competent person to
conduct frequent and regular
site safety inspections.
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
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
Identifying 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
Reducing Hazards
After a specific hazard(s) has been identified…
You can implement appropriate control method(s)
You can use appropriate PPE
PPE
CONTROL
Engineering Controls and Work
Practices
UV shields between the
worker and other
operations can protect
against exposures
Use work area barriers
to protect others working
in the same general
area
Barriers can also reduce
noise
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
Basic Safety Rules
1. Before you start make sure personal safety is followed.
2. Make sure you have had instruction
3. Release adjusting screw on regulators before opening
valves
4. Stand on the opposite side of the regulator when
opening a valve
5. Open cylinder valve slowly, oxygen first all the way open
acetylene just a quarter of a turn
6. Do not use or compress acetylene at pressure higher
than 15 psi.
Basic Safety Rules
7. Set working pressures as desired.
8. Light acetylene first, shut it off first
9. Never use oil on regulators or any equipment
10. Do not use oxygen as a substitute for compressed air
11. Keep heat, flames and sparks away from
combustibles.
12. Keep hoses out of sparks or spatter to prevent leaks