Metal Coatings and Welding Fumes: Understanding the Impact

Welding is an essential industrial process that joins metals to create a range of products. With the application of metal coatings to protect surfaces from corrosion, improve aesthetics, or enhance electrical conductivity, it becomes critical to understand how these coatings impact the fumes generated during welding.

Welding fumes are made up of a complex mixture of metallic oxides, silicates, and fluorides. These fumes are formed when a metal reaches its boiling point under the intense heat of the welding arc. This process produces vapor, which cools down and solidifies into the tiny particles constituting these fumes.

The presence of coatings can affect the boiling point of the surface metal and influence the vapor's composition. From a health standpoint, inhaling these fumes, especially when welding coated metals, can present various safety risks.

Learn More About Metal Coatings & Welding

A welder working on a metalworking project and using a FumeXtractors fume arm to extract smoke and fumes from above the source.

A variety of coatings can be applied to metals during welding processes, including:

Zinc Coatings (Galvanizing): Protects against corrosion.

• Effect on Weld Fume: Welding galvanized steel, coated with zinc, releases zinc oxide into the fumes.
• Health Risks: Inhalation of zinc oxide fumes can lead to metal fume fever
• Fume Volume: The presence of zinc increases the overall fume generation rate.

Cadmium Coatings: Provides corrosion resistance - usage has been reduced due to health concerns.

• Effect on Weld Fume: Welding metals with cadmium coatings produces cadmium oxide in the fumes.
• Health Risks: Cadmium is highly toxic and can damage the lungs, cause kidney disease, and is a potential carcinogen.
• Fume Volume: The volume of fume generation considerably increases when welding cadmium-coated metals.

Nickel Coatings: Used for corrosion resistance and lustrous appearance.

• Effect on Weld Fume: Nickel particles can be part of the welding fumes when welding nickel-coated metals.
• Health Risks: Nickel fumes can cause respiratory problems and are recognized as a potential carcinogen.
• Fume Volume: Nickel coatings moderately increase the fume generation rate.

Chromium Coatings: Provides a hard, smooth surface and corrosion protection.

• Effect on Weld Fume: When welding chromium-coated metals, such as stainless steel, hexavalent chromium can be produced.
• Health Risks: Hexavalent chromium is a known carcinogen and can lead to lung cancer and respiratory issues.
• Fume Volume: Chromium coatings can significantly enhance fume generation.

Paints and Organic Coatings: Applied for aesthetic or corrosion protection.

• Effect on Weld Fume: Welding on painted or organically coated surfaces can produce various compounds.
• Health Risks: Many paints release toxic fumes when burned, leading to respiratory issues, allergic reactions, or neurological effects.
• Fume Volume: The generation rate of fumes varies depending on the thickness and type of paint or organic coating.

A welder working on a project while smoke and sparks are emitting around them.

When metals with specific coatings are used for welding, the composition and volume of fumes emitted can significantly change. Coated metals often contribute to a greater volume of fumes, and the toxicity of these can be intensified if the coatings have hazardous ingredients.

Welding on coated metals increases the chance of health hazards. Breathing in these fumes can lead to respiratory issues, such as metal fume fever, bronchitis, and other long-term lung conditions. These fumes can also negatively impact the nervous system. When some coatings are exposed to the high temperatures of welding, they release carcinogenic compounds that can increase the risk of cancer for those exposed.

The welding industry continues to improve safety precautions, particularly in ensuring welders are well-informed about the hazards of the materials they work with. OSHA’s Hazard Communication standard requires employers to provide information and training for workers on hazardous materials in the workplace. This is especially relevant for fumes generated from welding processes and metal coatings.

Fume extraction systems have been developed as an indispensable solution to address occupational safety concerns. Welding fume extractors are built to remove contaminants at or near the source, ensuring that harmful contaminants are kept out of the airstream and away from respiratory zones.

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FumeXtractors systems are available in a full range of styles and configurations to meet the needs of any welding application. The details that make up each of our fume extraction systems have been handpicked by industry experts for maximum effectiveness.

Our welding fume extraction systems not only ensure a comfortable and safe work environment but they also help weld shops meet and remain compliant with regulatory guidelines.