ABSTRACT
In the Singapore Mass Rapid Transit Project (MRT), 11 km of underground tunnels were built between 21 September 1984 and 17 April 1987 using compressed air. 1737 compressed air workers (CAWs) were employed in the project. They underwent 188,538 man decompressions at the various compressed air work-sites. 160 CAWs developed Type I decompression sickness (DCS) and 4 developed Type II DCS. Knee, elbow and shoulder pain were the predominant presenting symptoms of Type I DCS. Two Type II cases showed peripheral and central nervous system dysfunction. The third case presented with vestibular disturbance and the fourth with ‘chokes’. The overall incidence of DCS was 0.087%. The adoption of strict medical selection, strict adherence to decompression procedures and the provision for acclimatisation of new starters contributed greatly to this low incidence. Prompt treatment of DCS accounted for the low relapse rate. The clinical presentation of DCS is discussed here. Prevention of DCS by health education and monitoring of the worksite environment and work practice are advocated.
