OCCUPATIONS, WAGES AND LABOUR ORGANIZATION
43
improvement of medical services in industry, including the care of industrial accident cases in particular; and the maintenance of healthy working conditions in factories and other workplaces.
The majority of industrial health problems can only be tackled by field inspection and investigation. It is the policy of the section to devote much time to field work, either by routine inspection of individual factories, or field surveys of industries in which specific health hazards are suspected or known to exist. During the year field surveys were carried out by the Industrial Health Section on the atmospheric dust concentrations in quarries and button factories; the use of leaded petrol in rubber factories; the atmos- pheric concentration of butyl acetate in artificial pearl factories; and the health of agricultural workers handling organic phos- phorous insecticides.
Notification of occupational diseases is not compulsory; cases may be discovered in the course of routine factory inspections, but more often cases are voluntarily notified by hospital doctors and private practitioners. Each case is investigated by the Industrial Health Section. A single case of occupational disease may draw attention to conditions potentially dangerous to many workers. Silicosis and dermatitis still constitute the most important-local occupational diseases.
The number of cases of occupational disease recorded during the year was as follows:
Dermatitis
Silicosis
Insecticide Poisoning Gassing
Total
31
14
1
1
47
Silicosis is the most serious occupational disease found in Hong Kong, and the number of cases on record is 43. It occurs in quarry workers and stone grinders. The majority of quarries in Hong Kong produce granite, which has a high free silica content. Pure quartz, which constitutes 100% free silica, is commonly used in the stone grinding industry. Preventive measures taken to eliminate the free silica dust hazard include the enclosure of quarry plant, and water spraying of the crusher feeds. The effectiveness of the latter is hindered during the dry winter months by water shortage,