Application and comparison of three risk assessment methods for occupational health risk assessment of dust in a sanitary ceramic product manufacturing enterprise

Objective Three methods were applied to conduct occupational health risk assessment for the working positions exposed to silicon dusts in a sanitary ceramic manufacturing factory， and the evaluation results were compared to explore the applicability of different occupational health risk assessment methods.

Methods One large sanitary ceramic product manufacturing enterprise in Songjiang District， Shanghai was selected to conduct occupational health risk assessment for the working positions exposed to silicon dusts， using occupational hazard risk index evaluation method， exposure ratio evaluation method， and International Council on Mining and Metals （ICMM） quantitative occupational health risk assessment method. The consistency of the evaluation results of the three methods was tested using weighted Kappa method.

Results Fourteen working positions exposed to silicon dusts were identified， and three positions had excessive dust concentration： composite forming position of phase 2 workshop （0.80 mg·m^-3）， addition forming position of phase 2 workshop （1.00 mg·m^-3）， and glazing position of 1F in phase 2 workshop （1.50 mg·m^-3）， with an excessive rate of 21.42%. The occupational hazard risk index evaluation method assessed 6 positions with no harm， 6 positions with mild harm， and 2 positions with moderate harm. The ICMM quantitative occupational health risk assessment method assessed 6 positions with potential risks， 2 positions with tolerable risks， and 6 positions with intolerable risks. The exposure ratio evaluation method assessed 8 positions with medium risk， 5 positions with high risk， and 1 position with extremely high risk. The consistency test results of the three evaluation methods were poor. The Kappa coefficient between the occupational hazard risk index evaluation method and the ICMM quantitative occupational health risk assessment method was 0.15. The Kappa coefficient between the occupational hazard risk index evaluation method and the exposure ratio evaluation method was -0.09. The Kappa coefficient between the ICMM quantitative occupational health risk assessment method and the exposure ratio evaluation method was 0.04. The RR values obtained by the three evaluation methods were significantly correlated： the correlation coefficients between RR_{ICMM quantitative assessment method} and RR_{exposure ratio evaluation method}， RR_{Occupational hazard risk index evaluation method} and RR_{ICMMquantitative assessment method}， RR_{Occupational hazard risk index evaluation method} and RR_{exposure ratio evaluation method} were 0.915， 0.604， and 0.594， respectively. The correlation between the assessment result level and C_TWA was strong.

Conclusion The occupational hazard risk index evaluation method is suitable for the working positions with low silicon dust exposure concentration， the ICMM quantitative occupational health risk assessment method and the exposure ratio evaluation method are suitable for the positions with high silicon dust exposure concentration， but all these three evaluation methods have limitations. It is more reasonable to use multiple methods at the same time in actual evaluation work.