ABSTRACT
To assess the adverse effects of dust on pulmonary function and to determine the association between subjective respiratory symptoms, cognitions about working environments and pulmonary functions, the study was conducted on 719 coal mine workers (395 workers on direct part, 324 workers on indirect part) being employed in a coal mine industry located in Hwa-Soon area. Questionnaires on respiratory symptoms and cognitions about working environments were filled out by themselves, and pulmonary function test was given by trained doctors. The results obtained were as follows ; 1. Significantly increased subjective respiratory symptoms prevalence were found in the workers on direct part comparing to workers on indirect part, and symptoms prevalence rate was higher in sputum, coughing, respiratory difficulty, palpitation and chest pain in order. 2. Significantly increased cognitions degree about working environments were found in workers on direct part comparing to workers on indirect part, and the degree was higher in dust concentration, temperature, working density and humidity in order. 3. FVC, FEV(0.5), FEF(200-1200ml) and FEF(25-75%) were lower for workers on direct part than that for workers on indirect part. 4. In workers on direct and indirect part, lung functions except FEF(200-l200ml) for the high subjective symptom group was smaller than that for the low group. There was not significane statistically, but the significane was found in FVC and FEVt in total coal workers. 5. In workers on direct part, FEVt and FEF(25-75%) for high cognition group about working environmental conditions was smaller than that for the low group but other lung functions were reversed. But in workers on indirect part, similar results was found and the significance was found in FEV(0.5) FEF(25-75%) and FEF(200-1200ml) in total coal workers. 6. Lung functions had negative correlation between sputum and FEF(200-1200ml).