Objective To provide a scientific basis for occupational disease control by analyzing the status and characteristics of occupational exposure to hard alloy dust.
Methods Five hard alloy manufacturing enterprises in Zhuzhou City were selected for occupational health investigation and hazard detection. We described the distributions of the hazards in different technological processes and enterprises of different sizes and assessed the relevant occupational health risks.
Results The ranges of air exposure level of tungsten and its alloys and cobalt and its alloys in selected workstations were < 0.015-6.46 mg/m3 (median, 0.09 mg/m3) and < 0.007-0.677 mg/m3 (median, 0.017 mg/m3), respectively. Batching and wet-grinding, drying, sintering, machining, and product packaging workers had air cobalt exposure levels higher than the national standard limit. There were significant differences in the air levels of tungsten and its alloys and cobalt and its alloys between the workers doing different types of work (P < 0.05). Workers were subjected to high-risk task at batching and wet-grinding workstation or drying workstation according to the results of risk assessment.
Conclusion The air levels of tungsten and its alloys and cobalt and its alloys in selected workplaces are above the national standard limit. Key control workstations are identified including batching and wet-grinding, drying, sintering, machining, and product packaging.
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