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Compressed Air Working in Chennai During Metro Tunnel Construction: Occupational Health Problems
1Consultant in Diving Medicine, Mumbai, India.
Summary
Chennai
Area of Science:
- Occupational Health
- Civil Engineering
- Public Health
Background:
- Rapid urbanization in Chennai necessitated a metro rail system.
- Two underground metro corridors were planned to meet transit demands.
- This involved extensive tunneling and work under compressed air conditions.
Purpose of the Study:
- To detail the occupational health center's role in managing compressed air work.
- To report on the health outcomes of workers during Chennai metro construction.
- To assess the safety protocols and suggest updates for Indian standards.
Main Methods:
- Selection and fitness assessment of workers for compressed air environments.
- Management of compression and decompression procedures.
- Health monitoring and treatment of decompression sickness.
Main Results:
- Over 35,000 man-hours were completed under compressed air (1.2-1.9 bar absolute).
- Only three cases of Type I decompression sickness were reported and successfully treated.
- Low incidence attributed to medical supervision, experienced operators, and reduced work hours.
Conclusions:
- Effective occupational health management ensured worker safety during compressed air tunneling.
- The Chennai metro project demonstrates successful implementation of safety measures.
- Urgent revision of Indian Standard IS 4138-1977 is recommended for modern tunneling practices.
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