The improvement of industrial safety and working environments of workers is one of the essential requisite for welfare society. Furthermore, such improvement is believed to lead to an increase in workers' productivity.
This study has two objectives. The primary objective is to investigate the effects of industrial safety and working environments of workers on their health status, job satisfaction and productivity. (the major hypothesis) The secondary objective is to study the implications of an investment for improvement of industrial safety and working environments.
The data on individual employees have been collected by administering questionnaires to 1156 workers employed by the 12 companies of three selected industries (furniture, construction, mining). The data on the companies' physical and general working environments have been collected by reviewing the selected companies' records. The data on the physical environments of working places have been collected with appropriate equipments borrowed from the Ministry of Labor.
Basically two lines of data analyses have been conducted: descriptive analyses of the data, and statistical tests of the major hypotheses and sub-hypotheses of the study.
Descriptive analyses of the major variables have been conducted by comparing frequency distributions of the key variables within and between industries. The significance of differences between those variables have been tested by chi-square tests.
Two-stage least squares are the statistical model used for the multivariate analyses. At the first stage, intermediate output variables (health and job satisfaction variables) were regressed on the input variables (environment and situational variables). In the second stage, final output variables (productivity measures) were regressed on the intermediate variables estimated by the first stage regressions and other instrumental variables.
The results of the analyses mostly confirm the hypothesized cause-effect relationships between environments, health, job satisfaction and productivity. It has been shown that an improvement of industrial safety and working environments of workers contribute to a better health and job satisfaction and also to an increase in productivity.
Implications of the findings are that businessmen should invest more in an improvement of industrial safety and working environments because such investment will increase the ptoductivity of workers and hence the profit of their firms. The findings also indicate that an investment for the improvement of the health of workers is a sound investment for the same reason.
This conclusion should be taken with a great deal of caution for the following reasons. First, due to data constraint, health status and job satisfaction are represented by proxy variables. Second, some of these proxy variables are constructed on the basis of the perception of employees, which are at best subjective measures. Third, even objective measure obtained by environmental tests can not be translated into uni-dimensional index of environments.
