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Asbestos exposure during routine brake lining manufacture
Hossein Kakooei1, Mahmod Sameti, Ali Akbar Kakooei
1Department of occupational Health, School of Public Health, Medical Science/University of Tehran, Tehran, Iran.
Industrial Health
|January 24, 2008
Summary
Workers in a brake lining factory experienced high asbestos fiber exposure, exceeding occupational safety limits. Airborne asbestos levels were significantly elevated during mixing processes, necessitating further investigation into workplace safety.
Area of Science:
- Occupational Health
- Environmental Science
- Industrial Hygiene
Background:
- Occupational exposure to asbestos is a significant health concern.
- Developing countries often have less stringent occupational safety regulations compared to developed nations.
- Brake lining manufacturing involves processes that can release asbestos fibers.
Purpose of the Study:
- To assess occupational exposure to asbestos fiber and total dust in a brake lining manufacturing plant in a developing country.
- To compare exposure levels with those in developed countries and established occupational exposure limits.
- To identify specific processes contributing to elevated airborne asbestos concentrations.
Main Methods:
- Time-weighted average monitoring of total dust and asbestos fiber concentrations.
- Personal air sampling using membrane filters.
- Analysis by phase contrast optical microscopy (PCM) for comparison with OSHA PEL.
Main Results:
- Elevated airborne asbestos levels were observed, particularly during mixing processes.
- Total dust concentrations ranged from 2.08 to 16.32 mg/m³, exceeding OSHA recommendations.
- Average asbestos fiber exposure (0.78 f/cc) was 7.8 times the OSHA Permissible Exposure Limit (PEL).
- Only chrysotile asbestos was detected in the air samples.
Conclusions:
- Routine processes in brake lining production can lead to significant airborne asbestos exposure.
- Workers are exposed to levels substantially higher than recommended occupational safety limits.
- Further research is required to address occupational asbestos exposure in this industry.
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