MIG Welding Fumes: Are They Harmful?

MIG Welding is an impactive industry, as welding services are used hand-in-hand with the building construction, automotive, and aviation fields. The welding industry has brought us many important things we use in our everyday lives. However, MIG welding can be quite dangerous if certain factors are involved.

MIG or Metal Inert Gas welding uses a shielding gas that protects the melted metal being worked with from airborne contaminants. When paired with the high heat of the welding torch and certain fillers in the metal material being welded, this gas can cause harmful, toxic fumes to outflow into the air.

Read on to find out what health risks you may face during the MIG welding process, how to stop inhaling the toxic welding fumes, and how to prevent creating them. You can also learn what hazardous substances are in MIG welding fumes and ways to make your welding shop a safer place by following OSHA standards.

Health Risks Related to Toxic Welding Fume Exposure

Ultraviolet radiation, caused by flames emitted when welding, can cause skin cancers and ocular melanoma in welders without proper protective gear. Long-term and, in some cases, short-term exposure to harmful MIG welding fumes can also cause acute or chronic health conditions and even death when inhaled by or absorbed through the skin of welders.

Allergic Contact Dermatitis

Some of the chemical compounds released when welding are hazardous and, when introduced to your skin, can cause skin rashes. Nickel, chromium, and silica rubber are all toxic chemicals found in MIG welding fumes, which can cause allergic contact dermatitis. The rashes or hives you can get with this condition are itchy, irritating, and cause feelings of prickliness and burning.

Asphyxiation

Since MIG welding can release so many toxic gases into the air, welders can be asphyxiated if they aren’t wearing proper respiratory equipment when welding. Because these gases can displace oxygen when welding in a confined space, welders must be permitted to weld in a small area to ensure their safety.

Some toxic gases present in MIG welding fumes that can cause asphyxiation include:

• Carbon monoxide
• Carbon dioxide
• Helium
• Nitrogen
• Argon

Respiratory Irritation

When inhaled, ozone gas and nitrous oxide can irritate welding workers’ respiratory tracts. High exposures of these fine particles of metal and toxic gases will cause coughing, dryness of the throat, and tightness of the chest or develop into a more serious health condition. This irritation usually only lasts for a short time unless there is continuous exposure to welders without gear.

Irritant-Induced Asthma

If a welder’s respiratory tract is continuously exposed to irritating and toxic welding fumes by not wearing the proper respiratory protection gear, they could eventually develop irritant-induced asthma. This condition causes the airways to swell, inflame, and produce extra mucus, making it hard to breathe. It may also cause welders to cough, wheeze, and experience chest pain.

Occupational Asthma

Much like irritant-induced asthma, occupational asthma is also caused by continuous exposure to toxic welding fumes without proper respiratory protection gear. Materials like chromium, cobalt, and nickel cause severe shortness of breath, chest tightness, coughing, wheezing, and reduced lung function when inhaled. All of these symptoms are apparent in this form of asthma.

Pneumonia

Because certain chemicals present in toxic welding fumes can cause decreased lung function when inhaled, welding workers are more susceptible to contracting pneumonia when continuously exposed to the fumes. This lung infection can be deadly for younger and older welders, although older welders are more at risk because they have a weaker immune system.

Chronic Obstructive Pulmonary Disease

Welders continuously exposed to toxic MIG welding fumes are more likely to contract COPD. This disease affects a welder’s everyday life by irritating, obstructing, and limiting their airflow through chronic inflammation of the lungs and can sometimes cause death.

The symptoms of this condition include:

• Shortness of breath
• Reduced function of the lungs
• A tight feeling in the chest area
• Wheezing
• Coughing
• Fatigue
• Exacerbation

Welder’s Lung

Iron oxide, which is the particles of iron and oxygen that make up rust, is present in MIG welding fumes and can get stuck inside a welder’s lungs if inhaled. Welder’s lung, or pneumosiderosis, is a lung disease that affects welders who continuously breathe in iron oxide particles over time. This condition can cause coughing, shortness of breath, and an overproduction of mucus.

Lung Cancer

Specific chemicals present in toxic MIG welding fumes are carcinogenic, meaning they can cause lung cancer if continuously inhaled over time. Some carcinogenic chemicals found in these fumes include beryllium, cadmium oxides, chromium, and nickel. These chemicals come from fillers in the types of metal being welded, like stainless steel, copper, and aluminum.

Kidney Cancer

Certain hazardous substances found in MIG welding fumes like asbestos, iron oxides, and nickel can increase the risk of kidney cancer when exposed in high amounts over a continuous period to welders aged between 59 and 74. High exposure to ultraviolet radiation from MIG welding can also take part in this age group of welders for higher risk of kidney cancer.

Neurological Disorders

Studies have shown that prolonged exposure to MIG welding fumes containing the toxic chemical element manganese can cause neurological symptoms similar to Parkinson’s disease in welders. This condition affects a welder’s mental ability and physical ability, obstructing their daily lives.

Some neurological symptoms caused by inhaling or absorbing manganese through toxic welding fumes include:

• Tremors
• Decreased or slowed movement
• Muscular rigidity
• Arm stiffness
• Leg stiffness
• Cognitive difficulties
• Freezing spells
• Impaired reflexes
• Loss of balance
• Problems with speech

Metal Fume Fever

Metal fume fever is a less severe illness similar to the flu that can affect a welder four to 12 hours after inhaling toxic welding fumes created by harmful substances inside galvanized metals or mild steel. This condition usually only lasts for a short while after stopping MIG welding fume exposure.

Symptoms of metal fume fever include:

• Chills
• Thirst
• Fever
• Aching of the muscles
• Soreness of the chest
• Coughing
• Wheezing
• Fatigue
• Nausea
• Metallic taste

Sources: PubMed, HSE, NCBI, MJA, AOCD, Oxford Academic, Cancer Council, The Fabricator

How Do You Stop Inhaling Welding Fumes?

By practicing proper safety techniques and giving your workers extensive training, they will understand the health importance of preventing the inhaling of welding fumes. However, with MIG welding, fumes are always going to be present because of its shielding gas. There are many ways to lower toxic MIG welding fumes created or prevent them from being breathed in.

Dodge the Fumes

Some welders tend to get close to their work or crouch over it to see their welds clearly and make sure they are perfect. This is dangerous, as it is possible to inhale fumes if your face is in their direct path. Welders should position themselves away from the metal being welded to prevent breathing in toxic MIG welding fumes as recommended for their safety by OSHA.

Use A Different Shielding Gas

The MIG welding process uses an external shielding gas to prevent airborne contaminants from affecting the integrity of a finished weld. It’s more common for welding shops to use pure carbon dioxide for shielding gas, but this gas requires more voltage used to melt the metal, meaning more toxic welding fumes will be generated. An argon blend is best and requires less energy.

Use Waveforms to Reduce Spatter

Spatter created by the MIG welding process can result in small metal particles to solidify and be carried by toxic welding fumes, making them even more dangerous if a worker inhales them. You can reduce spatter by using waveforms, as they control current quicker and more efficiently than a welder can. Waveforms allow welders to focus on their weld instead of the heat input.

Wear Personal Protective Equipment

Wearing the right personal protective equipment can prevent welders from breathing in or absorbing toxic MIG welding fumes through their skin. Personal protective gear can also prevent burns and injuries. It is the responsibility of a welding business’s management to ensure all welders are wearing proper protection for their safety.

Some examples of personal protective equipment a welder should wear to prevent inhaling or absorbing welding fumes through their skin include:

• Welding helmets with a wide viewing screen: These welding helmets allow welders to get a better view of their welds, so they won’t have to position themselves close enough to inhale toxic welding fumes.
• Welding helmets with a built-in fume extracting feature: These kinds of welding helmets directly remove fumes from the source for a more efficient way of preventing welders from inhaling fumes.
• Fire-resistant and electricity-resistant clothing: Fire-resistant hand shields, gloves, aprons, and boots will prevent welders from burns from the high heat welding gun or in case of a fire. They will also protect workers from electrocution when touching the metal parts of the electrode holder.
• Pants long enough to cover the tops of boots: A welding worker’s pants must be long enough to cover the tops of their boots so no sparks will fall into them. Welders should not cuff their pants because sparks can also catch on cuffs.
• Steel-toed boots: Metal is heavy, and even more so if combined with other metals in a finished weld. Welders can injure themselves if they drop a heavy weld, so they should wear steel-toed boots to prevent fractures or painful bruises.

Wear A Respirator

Ventilating a workshop doesn’t always reduce toxic welding fumes to a safe level. In this case, welders should wear a respirator, so they breathe in clean air rather than harmful substances and fumes that could be dangerous to their health. OSHA requires welding employers to provide a respiratory health program for their welders if and when respirators are needed for their safety.

Remove Material Coatings

If welders do not remove material coatings from the outside of the metal they’re welding before proceeding with the welding process, they could cause harmful MIG welding fumes to enter the air and compromise the integrity of the weld itself. Welders should always remove these coatings before welding.

Some methods to remove material coatings from metal include:

• Abrasive Blasting Method: This method uses an industrial abrasive blaster or sandblaster to remove caked-on paint or bonded rust.
• Angle Grinder with Flap Disk Method: This method first uses an angle grinder to remove most metal contaminants. Then go back in with a flap disc to remove any remaining coatings.
• Stripping Method: This method uses chemical stripping agents to remove rust or paint so they will easily scrape off without much elbow grease.
• Wire Brush Method: This method uses a wire brush to get into cracks and grooves for maximum contaminant removal of non-bonded substances.
• Vacuum Method: This method uses a wet slurry vacuum to suck toxic substances from entering the air when grinding or melting down contaminants from the outside of the metals.

After using these coating removal methods, welders should always use a cleaner like acetone to remove any residue from chemical strippers or contaminant particles and prevent toxic welding fumes.

Use A Fume Extractor

Welders can use personal localized fume extractors for the direct removal of toxic welding fumes from the source. Attaching a vacuum to the welding gun and welding arc or welding under a fume hood are some fume-extraction methods welders use. This is best for individual workers to prevent inhaling or absorbing toxic MIG welding fumes.

Ventilate Your Shop

MIG welding businesses can use local ventilators or general ventilation systems in their workshops like fume hoods, ventilated workbenches, fans, or opening windows and doors to reduce toxic welding fumes. This method is the best for a whole shop’s safety rather than just individual welders’ safety.

Sources: Weld Guru, Shop Metal Tech, OHS, Man Monthly, Welding Answers, Plant Engineering, ACRA

What Causes Welding Fumes?

Welding fumes are created when high heat from a MIG welding gun is introduced to metal coated in toxic materials, or a metal that contains dangerous filler materials is melted down into a weld pool. By vaporizing the coatings and metal, a chemical reaction is caused, releasing harmful gases or smoke containing fine metal particles into the air.

Some examples of metal fillers that can contain harmful substances and hazardous coatings that can cause toxic MIG welding fumes include:

• Aluminum
• Galvanized metals
• Stainless steel
• Mild steel
• Nickel alloys
• Non-ferrous alloys
• Chromate coatings
• Plastic coatings
• Cadmium plating
• Lead oxide primer paints
• Paints
• Metalworking fluids
• Rust inhibitors
• Chlorinated solvents
• Oils

Some examples of toxic substances that can be found in MIG welding fumes or are created by chemical reactions when welding certain materials include:

• Aldehydes
• Arsenic
• Asbestos
• Beryllium
• Carbon Monoxide
• Chromium
• Hydrogen Chloride
• Iron Oxide
• Lead
• Manganese
• Molybdenum
• Nickel
• Nitrogen Oxides
• Silica

Source: The Fabricator, CCOHS

Why Welding Safety Is Important

Keeping your workers safe is an even more crucial practice than MIG welding itself; welding in an unfit environment for worker safety can cause minor to extreme injuries through hazardous events like electrocution, fires, and even explosions. Violations to worker safety standards could result in citations, penalties, fines, and, in critical situations, criminal charges or prosecution.

Safe Work Practices According to OSHA Standards

There are policies that dangerous industries like welding must follow to ensure the safety of their workers, as a MIG welding business can be held accountable for any hospital bills for injuries or health conditions caused by improper practice, as well as repairs to a damaged workshop and broken welding tools.

Some examples of safe work practices for welding shops according to OSHA standards include:

• Welders should wear appropriate personal protective equipment to prevent ultraviolet radiation from burning exposed skin and uncovered faces from inhaling welding fumes.
• All MIG welding equipment should be inspected before beginning the job in case the welding tools are damaged, broken, or there are any exposed connections in the wires.
• Welders should make sure their protective gear is completely dry before touching the electrode holder’s metal parts and should never touch them with bare skin to prevent electrocution.
• Always ensure the workspace is clean and doesn’t contain hazards like flammable materials or toxic materials that can cause fires, explosions, or deadly welding fumes.
• Workers should participate in fire watching after a MIG welding job is completed for up to 60 minutes to monitor in case of smoldering fires.
• Welders should avoid oil-based degreaser baths or cover them up when welding to prevent introducing an open flame to flammable material.

OSHA Violations

Now that we know how to safely weld so workers will have less of a chance to be injured or have their health impacted by MIG welding fumes, it’s essential to know what counts as an OSHA violation to prevent citations, fines, and in some cases, prosecution.

If businesses allow their workers to perform any of these actions or perform any of these actions themselves, they will be committing OSHA violations by compromising their welders’ safety:

• Welding workers exceed the exposure time limit of eight hours to a specific group of toxic or hazardous substances listed in the OSHA Z-1 table
• A MIG welding business hires untrained welders who don’t know proper safety procedures and do not provide them suitable training, instructions to perform, or supervision for preventing injuries to their workers or fires to start in the workshop.
• A MIG welding business employer does not communicate or identify possible hazardous chemical materials present in a welder’s work area, including failing to label containers that hold dangerous chemicals or failing to provide safety sheets related to the chemicals.
• A MIG welding business employer does not train or provide information to their employees on or about a newly introduced hazardous chemical brought into the workshop.
• A welder practices MIG welding in a permit-required confined space containing a dangerous atmosphere or materials that could cause asphyxiation without the proper permit for working in that area.

Sources: EHS Daily Advisor, NTT Training, SafetyCulture, OSHA, BOC South Pacific, NFPA

Summary

MIG welding fumes can be dangerous when certain toxic elemental chemicals are present on or in the metal being welded, leading to severe health conditions and possible injuries to welders when inhaled. There are many ways to prevent your workers from inhaling these fumes or lower the fumes emitted so everyone can be safe and healthy.