Objective  Using 4 health risk assessment models to assess the occupational health risk of dust hazards in the brick and tile manufacturing industry, and provide methodological basis for the choice of optimized model for risk assessment of key occupational hazards in this industry.

  Methods  A total of 71 dust exposure positions in 18 typical brick and tile manufacturing enterprises in Sichuan Province were studied by field survey and the measurement of dust exposure level. Risk assessment of dust hazards was carried out using four risk assessment models, namely Improved Quantitative Grading Method, Comprehensive Index Method, International Council on Mining and Metals (ICMM) Occupational Health Risk Assessment Quantitative Method, and Occupational Hazard Risk Index Method.

  Results  The results of the improved quantitative grading method showed that the risk level ranged from 0 to Ⅲ, and 90.1% (64) positions were ranked as level Ⅰ. The comprehensive index method showed that most positions were ranked as medium risk (55, 77.5%) and high risk(16, 22.5%) The ICMM quantitative method showed that 46(64.8%), 18(25.4%) and 7(9.9%) positions were ranked high risk, extremely high and intolerable risk, respectively. The occupational hazard risk index method showed that most positions were ranked as no hazards(33, 46.5%) and minor hazards(30, 42.3%) among the five risk levels. The horizontal comparison analysis of the four risk results showed that the risk results of the comprehensive index method and the ICMM quantitative method were in good agreement (P > 0.05), and the methods mutually verified the reliability and stability of the risk results (P < 0.01). There was an instability among the evaluation results derived from other two methods(P < 0.01).

  Conclusions  Major parameters used in these 4 health risk assessment models used in the brick and tile manufacturing industry were free SiO₂ content, the exposure level and actual exposure characteristics. Both the improved quantitative classification method and occupational hazard risk index method considered all above parameters. The occupational hazard risk index method considered more comprehensive risk factors, and the comprehensive index method and ICMM quantitative method had better consistency of risk results. In addition to considering the applicability of the method itself, full consideration should also be given to method amendments based on industry categories and dust exposure levels when the optimized occupational health risk assessment methods in the brick and tile manufacturing industry is chosen in the future.