Attacking Weld Fume at the Source

The Occupational Safety and Health Administration (OSHA) and other safety regulatory bodies set the allowable exposure limits for weld fumes and other particulates, including hexavalent chromium, with the aim of protecting employees against potential health hazards in the workplace. Providing welding operators with proper ventilation during the welding process is an important step companies can take to help meet the standards — and to help provide a safe and comfortable work environment.

Companies may opt to invest in centralized fume extraction systems, which are designed to protect the entire shop area. These systems involve the installation of new ductwork and fans to remove fumes and are highly effective, but they are also more expensive than other options. A viable alternative for some companies is a fume extraction gun used in conjunction with a fume extraction device or localized filtration system.

Fume extraction guns are available in a variety of amperages (typically 300 to 600), cable styles and handle designs. As with any welding equipment, they have their best applications, advantages and limitations, as well as recommended techniques for achieving the best results.

The basics

Fume extraction guns operate by capturing the fume generated by the welding process right at the source, over and around the weld pool. The weld fumes removed by these guns are composed of a combination of the filler metal and base material.

Various manufacturers have proprietary means of constructing guns to conduct this action, but at a basic level they all operate similarly: by mass flow, or the movement of material. A vacuum chamber suctions the fumes through the handle of the gun, into the gun’s hose and through to a port on the filtration system (sometimes informally referred to as a vacuum box).

Typically, fume extraction guns are larger than regular welding guns, and include the vacuum and hose that are necessary to extract the fumes. Some manufacturers offer fume extraction guns with a vacuum hose swivel on the rear of the handle to make them easier to maneuver. Also, design advancements have minimized the handle weight and size to make the guns as light as possible for operator comfort, while still offering consistent fume extraction benefits.

Benefits of the Bernard® Clean Air™ E Fume Extraction Gun

The Bernard® Clean Air E™ fume extraction gun is designed to efficiently capture welding fumes at the source, helping to create a cleaner work environment. This gun is particularly well-suited for applications using solid welding wire and for operations in confined spaces, where fume extraction directly in the welding operator’s breathing zone is essential.

Industries that frequently benefit from this technology include shipbuilding, heavy equipment manufacturing, and general fabrication, especially when working with mild or carbon steel. Additionally, for applications in petrochemical industries or those involving stainless steel welding, where higher levels of hexavalent chromium are present, the Clean Air E™ gun provides an effective solution for improving air quality.

Designed for high-amperage and high-deposition rate applications, this gun performs best in flat and horizontal welding positions, where it can effectively capture rising fume particles. While fume extraction in out-of-position welding can be more challenging due to the natural rise of fumes, proper technique and positioning can help maximize effectiveness.

Maximizing Performance

The Clean Air E™ fume extraction gun operates similarly to a standard MIG gun, making it easy for welding operators to adapt to. To achieve the best results, consider these best practices:

Optimize Extraction Settings – Adjust the vacuum system like the Miller FILTAIR® 215 to balance fume capture without affecting shielding gas coverage.
Maintain Proper Gun Positioning – Keep the gun at the recommended angle to ensure optimal fume collection.
Perform Regular Maintenance – Clean the extraction system and gun components to maintain consistent performance.

By integrating the Bernard® Clean Air™ E fume extraction gun into your welding operations, you can enhance fume control while maintaining welding quality and efficiency. Fume extraction guns operate by capturing the fume generated by the welding process right at the source, over and around the weld pool. As with any piece of welding equipment, fume extraction guns benefit from preventive maintenance.

Flux-cored wire allows vacuum adjustment

Because flux-cored wire produces a slag, it generates more weld fume. However, one benefit of using self-shielded flux-cored wire, for example, is it allows the ability to increase the vacuum level of the gun. Welding operators can close off all the vents and utilize the long shroud. This action maximizes the vacuum at the front end of the gun without concern for disturbing the shielding gas, since there is none generates with self-shielded flux-cored wire. When using gas-shielded flux-cored wire, a 0 to 15-degree angle will help maximize fume collection.

Pause at the end

At the end of the weld, welding operators can pause for 10 to 15 seconds, holding the fume extraction gun in place without depositing weld metal. This action allows the gun to capture residual fumes as the weld bead is cooling.

Wire type determines stickout

The contact tip to work distance can be longer — about 1/2 inch to 3/4 inch — when welding with flux-cored wire and a fume extraction gun. With solid wire, welding operators should try to keep the stickout to 1/2 inch or less to maximize fume capture. These lengths are comparable to the stickout lengths used with standard MIG guns.

Experiment with the air control regulator

Some guns, like the Clean Air E™, incorporate a slider or toggle mechanism conveniently located on the gun handle, while others integrate this function internally.

This adjustability is essential for balancing fume extraction with shielding gas coverage. Too much suction can disrupt the protective gas flow, leading to weld defects like porosity, while too little may not effectively capture harmful fumes. By using the built-in adjustment feature, operators can increase or decrease suction as needed to maintain optimal fume control while ensuring proper weld protection.

Finding the right balance may require some trial and error. To optimize performance, welding operators should test the air control setting on scrap material before welding on a final product. This ensures that fume extraction is maximized without negatively affecting weld quality.

With the Clean Air E™ and other adjustable fume extraction guns, operators have greater control over their work environment—helping to improve air quality while maintaining welding efficiency.

Proper maintenance and consumable usage

As with any piece of welding equipment, fume extraction guns benefit from preventive maintenance. Caring for them is similar to caring for a standard MIG gun. Also note that using flux-cored wire with these guns requires more frequent gun maintenance than solid wire because of the slag and fumes it generates. Regular maintenance is important to help prevent a clog or spatter buildup, which can limit the fume capture rate.

Inspecting and maintaining the front end of the gun is key to optimizing fume extraction. Frequently inspect the nozzle and contact tip for signs of spatter buildup, which along with blocking the fume extraction can also obstruct shielding gas flow and cause weld defects. Spatter buildup also can cause consumables to fail prematurely. Replace the consumables if spatter buildup appears, or clean them according to the manufacturer’s recommendations.

Also, inspect the vacuum hose regularly for damage such as cuts or kinks, which can lead to loss of suction. Replace a damaged vacuum hose as necessary.

Regarding consumables, using the manufacturer’s recommended consumables package with a fume extraction gun helps optimize performance, as the guns are engineered to get the best results with specific consumables.

When in doubt about maintenance or any other aspect of using a fume extraction gun, consider working with a trusted welding distributor, certified industrial hygienist and/or the gun manufacturer to address any questions or concerns.

Fume extraction guns can provide results

In combination with many other variables in the welding operation — wire selection, specific transfer methods and welding processes, welding operator technique, and base material selection — fume extraction guns can help companies maintain compliance with safety regulations and create a cleaner, more comfortable welding environment. Proper use and maintenance of the equipment is important to get optimal results.

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