Abstract: Objective To understand the concentration of cement dust in nonmetallic mineral products industry in Guilin City,provide basis for the prevention of cement pneumoconiosis. Methods A total of 29 enterprises that produce cement dust in the non-metallic mineral products industry in Guilin City were randomly investigated. The places and positions that produce cement dust in the non-metallic mineral products industry in Guilin City were identified through the field investigation of occupational health,andon-site sampling and testing were conducted according to the national occupational health standards. Results In 2020,there were 29 enterprises with cement dust in the non-metallic mineral products industry in Guilin City. The content of free silica in dust of small enterprises was 0.79%-7.85%,and that of micro-enterprises was 1.47%-5.96%.The exceedance rates of total dust and respirable dust concentration in workplaces of small enterprises were 46.51% and 51.16%,respectively. The exceedance rate of total dust and respirable dust concentration in the workplace of micro enterprises were 29.73% and 29.73%,respectively.The exceedance rates of total dust and respirable dust concentration in positions of small enterprises were 31.67% and 53.33%,respectively. The exceedance rates of total dust and respirable dust concentration in positions of micro enterprises were 12.50% and 32.50%,respectively. There were no statistically significant differences in the exceedance rates of total dust and respirable dust concentration in workplaces among different scale enterprises（χ²=2.36,3.77,both P>0.05）,there were statistically significant differences in the exceedance rates of total dust and respirable dust concentration in positions among different scale enterprises（χ²=4.83,4.21,both P<0.05）.In the four positions of cement dust working sites detecting dust concentration-time weighted average（C_TWA）,the exceedance rate of total dust C_TWA in batching operation point was the highest at 85.71%,and the exceedance rate of respirable dust C_TWA in batching operation point was the highest at 64.29%.There were statistically significant differences in the exceedance rates of total dust and respirable dust detection results among different working sites（χ²=20.22,7.83,both P<0.05）. In the four positions of cement dust working sites detecting C_TWA,the exceedance rate of total dust C_TWA in cement grinding operation point was the highest at 42.11%,and the exceedance rate of respirable dust C_TWA in batching operation point was the highest at 75.00%.There were no statistically significant differences in the exceedance rates of total dust and respirable dust detection results among different working sites（χ²=3.26,1.28,both P>0.05）. Conclusions The concentration of cement dust exceeds the standard in workplaces and posts of nonmetallic mineral products industry,which is easy to cause the occurrence of cement pneumoconiosis in workers to a certain extent. The relevant functional departments should strengthen the supervision of occupational health,strengthen the supervision and law enforcement of occupational health,further implement the employer's main responsibility system,and protect the physical and mental health of workers.

Key words: Nonmetallic mineral products industry, Cement dust, Free silica, Dust detection