Abstract:Objective To understand the prevalence of chronic obstructive pulmonary disease (COPD) among workers in chemical industry and iron and steel industry in Nanjing Jiangbei New Area to explore the main occupational hazard factors and provide a useful guide for occupational protection of workers employed in related industries. Methods Among 9 509 chemical industry workers in Nanjing Jiangbei Hospital and 5 764 steel workers in Nanjing Nangang Hospital, respectively receiving occupational physical examination from January 1, 2019 to September 30, 2020, the data of pulmonary function and occupational information were collected, and the relevant occupational hazard factors in the patients confirmed with COPD were investigated. Results The prevalence of COPD in chemical workers [9.66% (919/9 509)] was significantly lower than that [13.55% (781/5 764)] in iron and steel workers（ χ 2=54.760， P <0.01）. The occupational hazard factors of COPD patients were mainly exposed to irritant gases (nitrogen oxides, ammonia, chlorine and benzene compounds) in chemical industry, accounting for 88.90% and were mainly dust (silica dust and metal dust) in iron and steel workers, accounting for 88.22%. Conclusions There is difference in the prevalence rate of COPD between chemical industry workers and iron and steel industry workers, and their related occupational hazard factors are different. The health of industrial workers can be protected by improving production process on the basis of different production technology .