Welding fumes are a common occupational exposure. Several different welding fumes can cause similar adverse health effects. Personal sampling of a welding operation at a manufacturing facility produced the following 8-hour time-weighted average (TWA) results for individual metal fumes.
Metal Fume Result OSHA PEL ACGIH TLV
Antimony 0.05 mg/m³ 0.5 mg/m³ 0.5 mg/m³
Beryllium 0.00001 mg/m³ 0.0002 mg/m³ 0.00005 mg/m³ (I)
Cadmium 0.025 mg/m³ 0.005 mg/m³ 0.01 mg/m³
Chromium 0.02 mg/m³ 1 mg/m³ 0.5 mg/m³
Copper 0.03 mg/m³ 0.1 mg/m³ 0.2 mg/m³
Iron Oxide 0.5 mg/m³ 10 mg/m³ 5 mg/m³ (R)
Magnesium Oxide 0.02 mg/m³ 15 mg/m³ 10 mg/m³
Molybdenum 0.003 mg/m³ 15 mg/m³ 10 mg/m³ (I)
Nickel 0.25 mg/m³ 1 mg/m³ 1.5 mg/m³ (I)
Zinc Oxide 0.3 mg/m³ 5 mg/m³ 2 mg/m³ (R)
(R) Respirable fraction (I) Inhalable fraction
Briefly summarize the primary health effects associated with overexposure to each type of metal fume, including both acute and chronic health effects. Explain what analytical methods you would use for evaluating health hazards in the workplace.
Identify the types of metal fumes that would produce similar health effects on an exposed worker. Assume that each listed metal can cause respiratory irritation. Use the equation in 1910.1000(d)(2)(i) to calculate the equivalent exposure (in relation to OSHA PELS) for the metal fumes with similar health effects based on the “Result” column in the table above. Discuss whether you believe any of the individual metal fume exposures or the combined exposure exceeds an OSHA PEL or an ACGIH TLV.