| Abstract: | This paper reports the health experience of compressed air workersduring construction of the Island Line Section of the Mass TransitRailway in Hong Kong. The requirements of CIRIA's Code of Practiceincluding specifications of the Blackpool Tables for decompressionprocedures and the employment of doctors to monitor the healthof exposed workers by regular examination were prescribed bylocal legislation. Over a 3 year period there were 394 716 man-decompressionsfrom pressures between 1 and 3-5 kg/cm2 with 2032 cases of acutedecompression sickness giving a bends rate of 0-52 per cent.The epidemiology followed the usual pattern of increase in bendsrate with increase in pressure and length of shift and withage. Most attacks occurred within a short period after decompressionand the majority of limb pains affected the leg. There werealso 10 cases of barotrauma and 22 cases of dysbaric osteonecrosisof which 7 resulted in some disability. The low incidence ofillness was an index of the effectiveness of the Code of Practiceas applied to a large scale compressed air work operation butthe toll of dysbarism, albeit small, underlines the problemthat there are as yet no decompression procedures which willprotect all men at all times and indicates the need for furtherresearch and work-site evaluation.
Requests for reprints should be addressed to: W. K. Lo, Occupational Health Division, Labour Department Headquarters, Harbour Building, 38 Pier Road, Central Hong Kong. |
