With flying sparks and brilliant flashes of blue light visible in any welding activity, most people are well aware that welders face serious safety risks on the job.
It’s not just sudden accident and injury they need to guard against, however. Toxic fumes from some welding processes may also cause health problems that range from bronchitis to Parkinson’s syndrome.
“I can’t think of any activity that is more hazardous than welding,” says Frank Burg, president of Accident Prevention Corporation and a member of the standards development committee of the American Society of Safety Engineers (ASSE).
Burg says one of the most hazardous aspects of welding is the fumes, a plume of minute particles produced by the molten metals and by gases released during the welding process.
One effect of exposure to fumes is “metal fume fever,” a flu-like sickness that goes away within 24 to 48 hours. While considered short-term, Burg says, the effects depend on the kind of metal used.
“If the work involves cadmium, it could kill you,” he says. “No one analyzes these metals before they weld on them (to determine content). They’re just guessing.”
According to the ASSE, the short-term effects of welding fumes also include nausea, coughing, bronchitis, pneumonitis (inflammation of the lungs), encephalopathy, shortness of breath, and eye, ear, nose, throat and chest irritation.
Metals found in welding dust and fumes, the organization says, include aluminum, nickel, manganese, lead, chromium, copper, iron oxide and cadmium oxides. Gases produced by fumes include carbon monoxide, fluorine, nitrogen oxide and ozone.
Exposure to fumes containing manganese — an element present in most metals and often added to carbon steel and stainless steel to increase strength — is also thought to be the cause of Parkinson’s syndrome — or manganese-induced parkinsonism — a Parkinson’s-like illness characterized by decreased co-ordination, difficulty walking, loss of balance, shaking and slurred speech.
“NIOSH (National Institute for Occupational Safety and Health) has been doing studies and are finding a good correlation between amount of manganese exposure and incidence of Parkinson’s syndrome,” Burg says.
Other long-term effects include heart disease, kidney damage, stomach problems, lead poisoning, lung and throat cancer and neurological problems. In fact, the ASSE says, many welders suffer from some sort of respiratory illness or pulmonary infection.
There are other hazards associated with welding, Burg says. Fire and explosion are among the most serious. Oxy-welding, or oxyacetylene gas welding, uses fuel gases and oxygen to weld metals. Acetylene is both flammable and an explosive, and the flame used in the process burns at an intense heat.
“You’re looking at the heat of the sun, over 6,000 degrees,” says Burg. He says welders should always wear proper personal protective equipment (PPE), including heavy-duty aprons and gauntlet gloves and clothing that doesn’t burn easily.
Welders have also been injured or killed by explosions or fires while working on pressurized containers, such as fuel tanks, says Bruce Cormier, a welding examiner at GRB Enterprises, which operates training and qualification centres. Containers should be thoroughly purged and cleaned before work begins, he cautions.
Burning of soft tissues, such as eyes and skin, he adds, can be caused by the ultraviolet radiation produced by arc welding — a technique in which an electric arc is created between an electrode and the base metal to generate heat.
“The eyes are particularly vulnerable,” Cormier says. “If anyone is looking at the arc and not wearing glasses, their eyes absorb the full spectrum of the UV radiation. They may have a burning on the inside of their eyes.”
The injury, called welder’s flash or arc eye, is sometimes painful but usually temporary.
Cormier says welders can avoid long-term damage by wearing welding hoods and safety glasses and by not staring at the arc. Clear glasses offer shortwave UV protection, but shaded glasses provide greater protection against UV radiation.
Dan Tadic, executive director of the Canadian Welding Association, says most welding processes are very safe as long as safety precautions are met.
“Welding safety equipment should be worn at all times, and CSA standard W117.2 needs to be adhered to by all industries,” Tadic says.
During cutting, he adds, safety glasses or goggles should always be worn; during grinding, a clear face shield that covers the entire front of the head should be worn to protect the face from burns caused by flying sparks. Welders should wear steel-toed boots and coveralls, which also protect against flying sparks.
“It depends on the working environment. Each environment requires special attention,” he says, “and different processes may require different safety gear.”
To prevent inhaling harmful fumes, he says, welders can use a fume extraction hood, which sucks the fumes away from the face.
They could also use a respirator mask. The most common of these covers the nose and mouth and filters out dust, odours and particulates. Another type of mask supplies a line of fresh air, pumped in from a compressed air cylinder, battery pack or compressor.
“If I’m working in a plant and there’s a lot of open space and air movement,” Tadic explains, “I would use a fume hood as a first option or straightforward welding fume respirator. If I’m working in a confined space, where there’s limited air movement and may be a build-up of harmful fumes, I would use a respirator that has an air-line supply.”
In addition, Cormier says, the risk of fumes can be reduced through proper ventilation or air circulation mechanisms that remove contaminants. An isolated welding booth or room that has its own air filtration or ventilation system can be set up.
Most welders, Burg says, also suffer back and neck problems from working in awkward positions. By arranging workstations so that work can be done in a natural, comfortable position, ergonomic hazards can be reduced.
The changing dynamics in the workplace over the last decade has seen more women taking on what have traditionally been male-dominated jobs in high-powered industries. But while the number of women workers in industrial settings, such as welding occupations, has increased in the last few years, the science of prevention may still be playing catch-up.
One current study, conducted by Nicola Cherry and Jeremy Beach, researchers at the University of Alberta’s School of Public Health, is examining whether welding affects women’s health in ways different to men.
The study, called Women’s Health in Apprenticeship Trades — Metalworkers and Electricians (WHAT-ME), will look at all work-related health conditions and reproductive outcomes for women in these trades.
“As more women are choosing to go into nontraditional jobs,” Cherry says, “we need to look closely again and
see whether the standards that are there which keep men safe also keep women safe.”
Data collected so far has revealed, among women who had recently become pregnant, more than half (55 per cent) had at least one metal in their systems above the laboratory norms for northern Alberta. Early results also seem to show a connection between welding and breathing problems.
“In an interim analysis,” Beach says, “we looked at the new onset of a number of different symptoms. Wheeze is one of those, and also upper respiratory-type symptoms, such as rhinitis.”
In addition to research being done to better protect women welders, Burg says much more work still needs to be done to protect welders, in general, against the hazards of work.
The first step is more research, he says. There is still a long way to go, he believes, to fully understand the long- and short-term health effects of welding.
By using the right PPE the risks of welding could be greatly reduced — unfortunately, many workers don’t.
“It would be much better to be proactive,” he says. “We can be proactive and prevent these health and safety problems.”
(If you are interested in participating in the WHAT-ME study, visit the website at www.whatme.ualberta.ca.)