Welding Fume Hazards: Dangers, Risks and How to Reduce Them

welding fume hazardsMIG welding is a highly productive and fast-paced welding method that gets the job done with the right equipment and protective gear. It is mainly used in the manufacture of plants, automotive, aircraft, apparatus, etc. MIG welding uses inert gases like argon in particular which protects the weld from oxidation due to external oxygen influence.

The welding fumes generated during welding are formed due to evaporation, condensation, oxidation, decomposition, pyrolysis, and combustion of supplementary materials, inert gases, and contaminated air.

This leads to three types of toxic substances:
  • Respiratory and lung-damaging substances
  • Toxic substances
  • Carcinogenic substances

Welding Fumes

Welding fumes are a complex mixture of metal oxides, silicates, and fluorides. These fumes are formed when a metal is heated above its boiling point and most of its vapors condense to form tiny particles. These tiny particles are generally from the electrode and the material that is being welded.

The exact composition of the welding fumes produced in your workplace can be determined by the welding process used and its applications. They are:

  • Metal dust particles are very tiny, around 0.0001 mm which is highly concentrated with fluorides, silicates, aluminum, antimony, arsenic, beryllium, cadmium, cobalt, chromium, iron, lead, manganese, molybdenum, nickel, silver, tin, titanium, vanadium, and zinc.
  • The fusion of metals like carbon monoxide, argon, carbon dioxide, helium, hydrogen fluoride, iron oxide, nitric acid, nitrogen, ozone, phosgene, etc.

Can welding fumes change their composition based on the metal being weld?

Yes, as welding fumes generally contain oxides of metals on which we are welding.
  • Silica and fluoride fluxes produce amorphous silica, metallic silicate, and fluoride fumes.
  • If these fumes arise from mild steel, welding consists of additive metals like chromium, nickel, manganese, molybdenum, vanadium, titanium, cobalt, copper)
  • Stainless steel consists of chromium and nickel in the fumes released with minimal amounts of iron.
  • Nickel alloys contain more nickel in their fumes than iron.

How do coatings affect welding fumes?

Sometimes toxic fumes can come from the coatings and residue of metals being welded. These constituents in the coating have bad effects on the surrounding air. It includes:
  • Metal-working fluids, oils, and rust inhibitors
  • Zinc on galvanized steel
  • Cadmium plating
  • Vapors from paints and solvents
  • Lead oxide primer paints
  • Plastic coating

What are the factors that affect a workers’ exposure to welding fumes?

  • Type of welding process
  • Composition of welding rod
  • Filler and base metal’s composition
  • Type of coating present
  • Workstation and its location
  • Ventilation units and work practices.

Short-term Problems

Short-term effects include metal fume fever, symptoms that occur four to 12 hours after exposure, cold, thirst, fever, muscle aches, chest pain, cough, shortness of breath, fatigue, nausea, and a metallic taste.

Welding smoke irritates the eyes, nose, chest, and lungs and causes coughing, shortness of breath, shortness of breath, bronchitis, pulmonary edema (pneumonia), and pneumonia (inflammation of the lungs). Nausea, loss of appetite, vomiting, constipation, and slow digestion are associated with gastrointestinal effects and welding smoke.


Welding Fumes and Their Consequences

Fume TypeSourceHealth Effect
AluminumAluminum components of some alloys, e.g., copper, zinc, steel, magnesium, brass, and fillers.Respiratory irritant.
BerylliumBeryllium is a hardening agent found in copper, magnesium, aluminum alloys, and electrical contacts.Metal Fume Fever.” A cancer-causing cell. Other long-term effects include damage to the lungs
Cadmium OxidesCadmium oxides are stainless steel and zinc alloys contain cadmium as well as coated materials.Respiratory irritation, sore throat, dry throat, chest pain, and shortness of breath. Chronic effects include renal failure and emphysema.
ChromiumChromium is mostly stainless-steel and high-alloy materials, welding rods. Also used as a coating material.Increased risk of lung cancer. Some individuals may develop skin irritation. Some forms are carcinogens.
CopperCopper alloys such as Monel, brass, bronze also include some welding rods.Severe effects include eyes, nose and throat irritation, nausea, and “Metal Fume Fever.”
FluoridesFluoride is a common electrode coating and flux material for both low- and high-alloy sheets of steel.The severe effect is irritation of the eyes, nose, and throat. Chronic exposures can lead to bone and joint problems. Chronic effects include fluid retention in the lungs.
Iron OxidesIron oxides are major contaminants in all iron or steel welding processes.Siderosis – a bad form of lung disease caused by carcinogens deposited in the lungs. Severe symptoms include irritation of the nose and lungs. Tends to clear up when exposure stops.
LeadSolder, brass, and bronze alloys, primer/coating on steels.Long-term effects on the nervous system, kidneys, digestive system, and mental capacity. It also causes lead poisoning.
ManganeseManganese is used in most welding processes, especially high-tensile steels.Metal Fume Fever.” Long-term outcomes may include problems with the central nervous system.
MolybdenumSteel alloys, iron, stainless steel, nickel alloys.Severe effects include eye, nose, and throat irritation, and shortness of breath.
NickelStainless steel, Inconel, Monel, Hastelloy, and other high-alloys, welding rods, and coated steel.The severe effect includes irritation of the eyes, nose, and throat. There is an increased risk of cancer in occupations other than welding. Associated with dermatitis and respiratory problems.
VanadiumVanadium is an alloy of some steels, iron, stainless steel, and nickel.Irritation of eyes, skin, and respiratory tract. Chronic effects include bronchitis, retinitis, pneumonia, and pneumonia.
ZincGalvanized, painted metal.Metal Fume Fever.



Source and Health Problems due to Welding Gases

Gas TypeSourceHealth Effect
Carbon MonoxideCarbon monoxide arc formed.It rapidly integrates into the bloodstream and can cause headaches, dizziness, or muscle weakness. High concentrations can lead to unconsciousness and death.
Hydrogen FluorideCoating the rod with hydrogen fluoride.Irritation to the eyes and airway. Excessive exposure can damage the lungs, kidneys, bones, and liver. Chronic exposure can lead to chronic irritation of the nose, throat, and airways.
Nitrogen OxidesNitrogen oxides formed in the arc.Irritation of eyes, nose, and throat at low density. Concentrated abnormal fluid in the lungs and other serious consequences at high density. Long-term outcomes include respiratory problems such as emphysema.
Oxygen DeficiencyLimited areas of oxygen deficiency, welding in gas conservation, and gas exchange.Dizziness, mental confusion, shortness of breath, death.
OzoneOzone is formed during welding arc, especially in plasma-arc, MIG, and TIG processes.Severe effects include fluid in the lungs and bleeding. Very low concentrations (e.g. one in a million) can cause headaches and dry eyes. Long-term outcomes include significant changes in lung and lung function.


Are there ways to prevent exposure to welding gases?

  • Using substitute solvents like water-based cleaners or other solvents that have a high flash-point.
  • Always remember to degrease the containers where you store your metal and shielding gas.
  • Never weld on wet surfaces or those metals which have moisture on them with a degreasing solvent.
  • Do not use a chlorinated hydrocarbon degreaser as it corrodes the welding metal.
  • Prevention of accumulation of toxic gases and too much oxygen can be done if you can maintain a good amount of air circulation to avoid fire.
  • Always wear appropriate respiratory protective equipment. Mechanical ventilation units must also be installed to keep the air around you clean and pure.

Choosing your welding respirator

Choosing a welding respirator for yourself is important to reduce the possibilities of inhaling any sort of welding fume and there are two major ways by which air is supplied to a respirator which are:

  • A powered air-purifying respirator (PAPR) is a respirator that has a battery-powered filter that purifies the air and supplies air to the respirator. If your welding is not open with minimal airflow, then this is the type of respirator to go with. This respirator is placed on your back to prevent breathing any of the toxic fumes from the weld.
  • A supplied air system uses a compressor that is kept outside your workstation, and the air is drawn from a large cylinder to your welding helmet via a hose and control valve that controls the flow. Both of these respirators filter all the toxic particulate matter. Hence, it is necessary to be aware of the quality of air that you supply to your respirator.


1. Is welding fume a carcinogen?
Compared to MAG welding, MIG welding produces lower levels of welding fumes, however, the risks can be identified by looking at the details. Welding of aluminum materials releases welding fumes containing aluminum oxide. This hazardous substance is classified as dangerous to the lungs and causes dust mites in the lungs and most of all in the lungs.

Welders fall ill with irreversible aluminosis – a professional disease that applies to compensation in Germany. The duration of exposure is shorter than the severity of the disease. Irritation of the airways can also occur.

Ozone hazards should also be considered when making MIG welding aluminum alloys. The gas is formed by the formation of an arc along with a small number of welding fumes. Ultraviolet rays prevent their spread as they emit fewer welding fumes. In addition, they reflect hollow surfaces of aluminum and stainless steel.

In this way, ozone is released into the office environment. Excess dust promotes the depletion of the oxygen of this volatile gas. Ozone inhalation can lead to mucosal irritation, gas poisoning, or s edema of the lungs causing severe irritation. Ten times more ozone is produced during MIG welding than during the WIG welding process.

Some of the cancer-causing constituents are:
  • Chrome(VI): Irritation and chemical burns to the mucosa
  • Lead oxide: Nerve and kidney damage / Nausea
  • Nickel oxide: Carcinogen in the respiratory organs
  • Beryllium oxide: Metal fume fever / Chronic pneumonia
  • Cadmium oxide: Mucous membrane irritation / Hyperinflation
  • Cobalt oxide: Respiratory organ damage
  • Ozone: Mucous membrane irritation / Acuteirritant gas poisoning / Delayed pulmonary edema
  • Formaldehyde: Severe mucosa irritation
2. How does welding fume extractor work?
A fume extractor is a system that uses a fan to inhale smoke and particles into a system that purifies the air of harmful chemicals and particles. Industrial processes produce fumes or particles such as welding, sanding, grinding, spraying, dust filling, and chemical applications. Fume extractors use a variety of filters, and some systems, depending on the application, use multiple filters in a row.

Powerful fan and high-quality filter medium create recirculation of air pattern for non-duct units. Due to ventilation, no ductwork or expensive re-air installation is required. These units take up less space, are lighter, have higher power efficiency, and have easier access to replace filters.

3. What does weld fume consist of?
As far as research has been done, it is found out that welding smoke is a mixture of very fine particles (fumes) and gases. Many substances in welding fumes include chromium, nickel, arsenic, asbestos, manganese, silica, beryllium, cadmium, nitrogen oxides, phosphine, acrolein, fluorine compounds, carbon monoxide, cobalt, copper, ozone, and ozone.

4. What are the mild steel welding fumes?
Exposure to smoke from mild steel welding exacerbates health hazards. According to research by the International Agency for Research on Cancer (IARC), mild steel welding fumes are now considered cancerous. Welding fume cells are so small that when they are inhaled, they penetrate deep into the lungs and are deposited and absorbed by the body.

The allowable maximum concentration of the hazardous substance in healthy adults rather than recurrence in health consequences is the professional exposure limit. OELs are published by regulators and are considered acceptable or regulatory. OEL is the density of an object that a person can expose for a specific period of time, such as an eight-hour shift.

In the case of welding fumes, OELs are released as the allowable concentration in milligrams of metallic fumes per cubic meter of air. For example, five milligrams per cubic meter of OEL for iron oxide welding fumes in Alberta.

5. What is a welding fume extractor?
A fume extractor is a device that uses a type of activated carbon filter along with a fan to remove all the smoldering smoke and poisonous gases from the workplace. For beginners, the fume extractor is a device that utilizes a fan to suck any sort of hazardous fumes and some toxic gases.