Chemical Hazards

Because of the chemicals sometimes used for hot work, significant hazards may exist in the form of inhaled gases and vapors. OSHA requires proper ventilation whenever the possibility of toxic gas accumulation exists.

When brazing and gas welding fluxes contain fluorine compounds, the labels must reflect the hazards associated with fluorine compounds including eye and respiratory tract effects.

When brazing filler metals contain cadmium in significant amounts, the labels must reflect the hazards associated with cadmium including cancer, lung and kidney effects, and acute toxicity effects.

OSHA requires that all filler metals and fusible granular materials carry the following notice, as a minimum, on tags, boxes, or other containers: "CAUTION - Welding may produce fumes and gases hazardous to health. Avoid breathing these fumes and gases. Use adequate ventilation."

Unless atmospheric tests have established that an operator's toxic gas exposure is within the acceptable concentrations when welding or cutting indoors, outdoors, or in confined spaces, local exhaust ventilation and airline respirators must be used when working with base and filler metals containing the following toxic elements:

• Zinc
• Lead
• Beryllium
• Cadmium
• Mercury

To learn more about Hot Work visit our General Hot Work Online Training web page.