745 Welding, Cutting, and Brazing Safety

Chemicals

Proper ventilation is necessary in several welding and cleaning tasks to protect workers from harmful fumes and gases. Without good airflow, dangerous substances can build up in the air and lead to health risks or fire hazards. For example, dangerous chemicals that require ventilation while welding, cutting, and brazing include the following:

Fluorine Compounds: A fluorine compound is one that contains fluorine as an element in chemical combination, not as a free gas.

The National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA) have established the same exposure limits for fluorine compounds:

• Recommended Exposure Limit (REL) – NIOSH: TWA 0.1 ppm mg/m³)
• Permissible Exposure Limit (PEL) – OSHA: TWA 0.1 ppm mg/m³)

(TWA = Time-Weighted Average over an 8-hour work shift)

The American Welding Society (AWS) suggests the following cautionary label for brazing and gas welding fluxes containing fluorine compounds:

• "WARNING: This product contains fluorine compounds, which may release hazardous fumes when heated. Exposure to these fumes can cause irritation of the eyes, nose, throat, and respiratory tract. Use only in well-ventilated areas or with appropriate respiratory protection. Avoid prolonged or repeated exposure. Refer to the Safety Data Sheet (SDS) for more information."

Hexavalent chromium (Cr(VI): Hexavalent chromium (Cr(VI)) is a toxic form of the element chromium and is generally man-made.

Hexavalent chromium can be found in welding fumes, metal plating, paints, and industrial chemicals, making it a serious occupational hazard for workers in manufacturing, construction, shipbuilding, and automotive industries. Exposure to Cr(VI) poses significant health risks to workers, making awareness and safety measures critical.

Workplace exposure to Cr(VI) can lead to serious health effects, including:

• Cancer Risk: Prolonged exposure to airborne Cr(VI) is a known cause of lung cancer in workers. There is also evidence linking Cr(VI) to cancers of the nasal passages and sinuses.
• Respiratory Damage: Irritation and inflammation of the nose, throat, and lungs.
• Chronic Exposure: Chronic exposure may lead to bronchitis, asthma-like symptoms, and permanent lung damage. Perforation of the nasal septum (erosion of tissue between the nostrils) in extreme cases.
• Skin and Eye Irritation: Skin contact with Cr(VI) may cause dermatitis, rashes, burns, and ulcers. Eye exposure can lead to severe irritation, redness, and potential damage.

To see more information on the various chemicals listed above, you can visit the OSHA's Occupational Chemical Database.

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