Short-Term Health Effects of Welding Fumes

Short-term or acute health effects may develop during exposure or shortly afterwards. The symptoms experienced can depend on the welding process, materials, surface coatings, exposure level and effectiveness of the control measures.

Metal Fume Fever

Metal fume fever is a flu-like illness commonly associated with welding or carrying out hot work on galvanised metals. High exposure to mild-steel welding fumes may also cause the condition.

Symptoms can include:

• Fever
• Headaches
• Chills
• Muscle aches
• Nausea
• Tiredness and general weakness

Symptoms often begin several hours after exposure and may continue for some time after the exposure ends. Although metal fume fever does not usually cause lasting harm, its occurrence indicates that welding-fume exposure has not been adequately controlled.

Irritation of the Airways and Lungs

Welding fumes contain gases and extremely fine particles that can irritate the respiratory system. Even relatively brief exposure may cause:

• Dryness or irritation of the nose and throat
• Coughing
• Chest tightness
• Wheezing
• Shortness of breath
• Eye irritation

People who already have asthma or another respiratory condition may experience a significant worsening of their symptoms following exposure.

Very high exposure to respiratory irritants can cause acute irritant-induced asthma. Extreme exposure to certain gases, including ozone, can also cause serious lung damage.

Increased Risk of Pneumonia

Welders have an increased risk of developing pneumococcal pneumonia. This infection can be severe and, in some cases, fatal.

Employers should consider the relevant occupational-health guidance, including whether pneumococcal vaccination should be offered. Vaccination does not replace the need for effective welding-fume controls.

Long-Term Health Effects of Welding Fumes

Repeated or prolonged exposure to inadequately controlled welding fumes may cause chronic health conditions. Some effects develop gradually and may not become apparent until considerable damage has occurred.

Lung Cancer and Kidney Cancer

All welding fumes can cause lung cancer and may cause kidney cancer. This applies to fumes from all types of welding, including mild-steel welding.

There is no known completely safe level of exposure to welding fumes. Employers must therefore use effective controls and reduce exposure as far as reasonably practicable.

Chronic Lung Disease

Long-term exposure to welding fumes may contribute to reduced lung function and chronic respiratory illness. Evidence suggests that exposure may contribute to chronic obstructive pulmonary disease (COPD), which can cause:

• Progressive shortness of breath
• Persistent coughing
• Chest tightness
• Wheezing
• Fatigue

Welder’s Lung

Welder’s lung describes the deposition of inhaled metal particles within the lungs. It is a form of pneumoconiosis and may make the symptoms of other respiratory conditions, including COPD, worse.

Occupational Asthma

Some metals contained in welding fumes can act as respiratory sensitisers and cause occupational asthma. These include:

• Hexavalent chromium
• Nickel
• Cobalt

These substances may be present in stainless-steel welding fumes and can be produced in greater quantities by certain welding processes.

Occupational asthma symptoms may include severe shortness of breath, wheezing, coughing and chest tightness. Symptoms can develop after months or years of workplace exposure.

Hazardous Gases Produced During Welding

Welding can produce hazardous gases as well as airborne metal particles. Depending on the welding process, materials and working environment, these gases may include:

• Ozone
• Nitrogen oxides
• Carbon monoxide
• Shielding gases that can displace oxygen

Ozone and Nitrogen Oxides

Ozone may be produced during TIG welding, particularly when welding stainless steel or aluminium. It can irritate the throat and lungs, causing coughing and chest tightness. Very high exposure may cause serious lung injury.

Nitrogen oxides produced during arc welding can also irritate and damage the respiratory system.

Carbon Monoxide and Oxygen Displacement

Carbon monoxide can prevent the blood from carrying oxygen effectively. Symptoms of exposure may include:

• Headaches
• Dizziness
• Nausea
• Weakness
• Confusion
• Loss of consciousness

Shielding gases can also accumulate and displace oxygen, particularly in enclosed or confined spaces. This can cause unconsciousness, asphyxiation and death.

Welding Fumes Can Affect Other People

The risks are not limited to the person carrying out the welding. Colleagues, contractors, visitors and other people nearby may breathe in welding fumes if they are allowed to spread through the workplace.

Employers must consider everyone who may be exposed when completing a COSHH risk assessment and selecting suitable control measures.

Preventing Exposure to Welding Fumes

Employers must prevent or adequately control exposure to welding fumes. Depending on the activity, appropriate precautions may include:

• Using an alternative joining process that does not produce welding fumes
• Selecting a welding process that produces less fume
• Using suitable local exhaust ventilation
• Providing adequate general ventilation
• Using suitable respiratory protective equipment where required
• Keeping the welder’s head out of the rising fume plume
• Maintaining and testing all exposure-control equipment
• Providing workers with suitable information, instruction and training

No welding task should be treated as risk-free simply because it takes only a short time. Suitable controls must be in place before welding begins.

Key Welding-Fume Health Risks

• All welding fumes are hazardous and can cause lung cancer.
• Short-term exposure can cause metal fume fever and respiratory irritation.
• Welders have an increased risk of pneumococcal pneumonia.
• Long-term exposure may damage lung function and contribute to chronic lung disease.
• Chromium, nickel and cobalt can cause occupational asthma.
• Welding gases may cause poisoning, lung injury or asphyxiation.
• People working near welding operations must also be protected.