• Manual Welding creates smoke and fumes.
• Exposure to welding fumes can cause numerous health problems. When inhaled, welding fumes can enter the lungs, bloodstream, brain nerve cells, spinal cord and other organs and can cause both short- and long-term health effects.
• Weld processes in this table are ranked from most fume producing to least fume producing.
• Many different substances such as Chromium, Manganese, Nickel and Zinc may be found in welding fumes.

“Welder’s Guide to the Hazards of Welding Gases and Fumes”

View Additional Resource Links & Downloads

The following links provide further information on OSHA’s regulations

• Welding, Cutting, and Brazing
• OSHA FactSheet: Controlling Hazardous Fume and Gases during Welding

In additional, recommendations are made by the ACGIH (American Conference of Governmental Industrial Hygienists);

Tables of Regulatory and Recommended exposure limits for substances are available here:

• Annotated OSHA Z-1 Table
• Annotated OSHA Z-2 Table

The American Welding Society also makes available important information regarding safety in welding, they have available for free download the standard Z49.1:2012 – Safety in Welding, Cutting, and Allied Processes;

http://www.aws.org/safety/

How to Control Welding Smoke and Fumes:

The type of equipment that is appropriate for your process depends on how hazardous the fume is, and how large the weldments are, as well as other factors. Some factors to note:

• Stainless steel, especially in MIG welding processes, generally requires source capture methods to control the fume very closely to keep low exposure to Hexavalent Chromium that is present in the fumes.
• Mild steel can be controlled with Source Capture or Ambient and General Ventilation.
• Aluminum has the potential to cause explosions, when fine aluminum dust or chips are contained in a confined area, such as a dust collector. Regulations on explosive venting must be followed as per government requirements.

Equipment to Control Robotic Welding Smoke and Fumes

Source Capture Equipment:

• Fume arms are generally not appropriate to capturing fumes from automated processes, as they need to be positioned by a worker to keep near enough to the weld location to have effective capture.

• Overhead hoods are a very effective method in controlling smoke from welding robots as the smoke is kept in a contained environment, to be captured by an intake device in to the air filtration unit. Note that if workers are located within the enclosure, higher rates of ventilation may be required, to keep fume from exceeding Permissible Exposure Limits.