Ergonomics for the improvement of health and safety of female workers in industrially developing countries

Abstract: The thesis presents the results of an ergonomics survey which contains eleven studies in five different industries of Thailand and four different industries of Japan (Papers A to K). The aims of the studies were; (i) to identify priority problems of female workers in different industries from ergonomic points of view; (ii) to analyze and investigate these problems; (iii) to examine the ergonomics intervention practices at work places; and iv) to develop a practical method for appropriate ergonomics interventions at work for improving health and safety of female workers, particularly in industrially developing countries. The survey consisted of four parts; (i) general information about ergonomics problems with regard to working conditions and environments of female workers which were obtained through preliminary research studies; (ii) preliminary survey of ergonomics problems regarding health and safety of female workers in different industries in Thailand; (iii) selection of two different industries of Thailand to carry out more detailed studies of physical and psycho-social problems, particularly related to musculoskeletal disorders; and (iv) examination of the ergonomics intervention practices at work places by case-study in Japan and Thailand. Methods used in these studies were; (i) ergonomics checklist; (ii) working environmental measurements; (iii) questionnaire study for subjective feeling of fatigue; (iv) grip strength and back and leg strength tests; (v) hearing test; (vi) questionnaire study for the assessment of musculoskeletal disorders in various parts of the body; (vii) psycho-social questionnaire study for analysis of stress at work as well as in daily life situation; (viii) anthropometric measurements of the standing and sitting positions; (ix) work posture analysis, using OWAS method; (x) job analysis, using AET method; (xi) simple clinical and physical fitness tests for checking musculoskeletal disorders; and (xii) using three different questionnaires, i.e., interviewing management, employees and governmental officers for examining ergonomics intervention practices at work places. The results showed that the female workers in different industries of the two countries had experienced musculo-skeletal discomforts in various parts of their body and work stress. The reasons for the high prevalence of such problems seem to be multifactorial and complicated. For instance, the female workers have prolonged standing or sitting postures during work, operating machines which are not appropriately designed, and doing heavy manual material handling. They adopt awkward work postures which usually lead to musculoskeletal disorders. The association between work postures and symptoms problems is a factor of exposure time. It becomes obvious that ergonomics problems related to occupational health and safety of the female workers in this survey seem to have cause-effect responses which could be classified into three main categories; (i) poor working practices and workplace programmes without sufficient knowledge of ergonomics principles; (ii) lack of adjustment to local population of imported machinery and equipment and their use; and (iii) lack of appropriate work organization. The tri-partites (management, employees and governmental officers) of the two countries had the same opinion about the importance of the ergonomics intervention programme. They desired co-operation and more participation approach to achieve better success in their intervention programmes. However, they had some shortcomings in their intervention programmes; such as lack of co-operation among industrial staff, lack of budget and human resources, differences in attitudes or awareness between the management and the employees with regard to occupational health and safety, lack of managerial support, lack of technical knowledge and unclarity of government policy. Based on the results, a practical method of ergonomics intervention at work is developed for improvement of working conditions of female workers which combines the following two characteristics: (a) participatory ergonomics training in order to develop awareness and understanding of practical ergonomics principles, and (b) industry-level promotional activities to facilitate voluntary participation and co-operation between managers, workers and government officers. In addition, further research activity is continuously needed for ergonomics implementation, particularly in the industrially developing countries.