Welding helmets protect the eyes and face from UV radiation and sparks, but typically don’t protect workers from toxic welding fumes and gases. When metal is melted by heat and flames, a chemical reaction occurs, producing hot fumes and gases that rise into the air. Without proper controls, these fumes and gases can surround the welder and enter their breathing space. This exposure can lead to a range of health issues—from temporary symptoms like fever and cough to more serious conditions such as cancer.  

What your employees need to know about welding fumes

Make sure workers understand these critical points:

Safer materials. The best way to control fumes is by using less harmful materials or those that produce less fume. Avoid consumables and base materials containing highly toxic substances, such as cadmium and lead.

Ventilation is key. Avoid welding in small, unventilated spaces. These environments can result in high exposures to fumes. Factors like welding duration and voltage also influence the level of exposure.

Local exhaust ventilation (LEV). LEV is one of the most effective ways to control fumes. Position the exhaust system close to the weld so it pulls fume away from the welder before they can breathe it in. If the system doesn’t pull enough air, or it recirculates contaminated air, it will not provide adequate protection. Opening windows or using HVAC systems doesn't always control the high concentrations around the welder.

Respirators. Even with good ventilation, overexposure is common for welders. Respiratory protection should always be available. In situations where other controls are impossible or inadequate, respirators become necessary.

Understand respirator limitations. Cartridges designed to remove gases or solvent vapors will not filter welding fumes. Particulate filters only remove fumes, not gases. And neither supplies oxygen. If the welder has facial hair or an object like a hoodie under the seal of a tight-fitting respirator, it can cause leaks.

PAPR helmets. Some welding helmets come with built-in respirators, such as loose-fitting powered air-purifying respirators (PAPRs). These helmets provide enhanced protection and comfort, typically without requiring shaving or fit testing.  

What your employees need to do to control welding fumes

To effectively control welding fumes, instruct your workers to:

  • Know what they are welding. Identify the chemicals present in welding materials and choose a safer alternative. Examples, as referenced earlier, might be free of cadmium or lead or generate less fume.
  • Remove hazardous coatings. Before welding, safely remove any coatings, such as oil or lead paint, so they don’t produce additional hazardous exposures.
  • Prioritize ventilation. Whenever possible, use ventilation before relying on respirators. Use local exhaust when possible.
  • Stay out of the plume. The farther a worker’s face is from the weld, the better. For example, stay upwind when welding in open or outdoor environments.
  • Keep distance between welders. If multiple workers are welding at the same time, ensure they are spaced far enough apart to avoid exposing each other. Keep non-welders away from the fume.
  • Keep respirators on. Even after the welding gun is off, welders should continue wearing their respirators when fumes linger. They should also wear them when using powered tools to grind welded materials. Sometimes the welder will have to wear the equipment for an entire work shift.
  • Report broken controls. Welders should promptly report any malfunctioning respirators or ventilation systems to their supervisor.

To determine if welding fumes are under control, a qualified professional must measure your employees’ exposures. The professional does this with specialized equipment that collects or responds to air contaminants. 

What to cover at your safety meeting on welding fumes

Make sure your workers understand the health risks associated with welding fumes. Teach them how to recognize the signs of overexposure, and review the safety data sheets for the materials they use.

Hands-on training is crucial. Demonstrate how to properly use equipment such as ventilation systems and respirators. Emphasize the importance of using them properly during welding and related tasks.

Finally, check whether your workers understand the training content.

Properly controlling welding fumes is vital for the health and safety of your workers. When they use effective controls, they reduce the risk of risk of cancer and other serious illnesses.

(Rev. 07/2025)