Abstract:
Objective To study the application of combined risk assessment method and literature analogy method to the pre-assessment of occupational hazards in waste-to-energy projects.
Methods Through literature review, we analyzed occupational hazardous factors and corresponding concentrations (intensities) in waste-to-energy projects. We used risk assessment equation R=MLSN to calculate a risk value R of each occupational hazardous factor, then a risk value Rg of occupational hazards in each assessment unit, and finally a risk value I of occupational hazards in a selected construction project. The risk levels and risk degrees of occupational hazards in a proposed construction project were determined accrording to I value classification standard.
Results Literature analogy results showed that the main occupational hazardous factors in waste-to-energy projects included dust, noise, and high temperature, followed by industrial toxicants, power frequency electric field, and biological factors. Among them, dust, industrial toxicants, high temperature, and power frequency electric field monitoring results did not exceed occupational exposure limits for hazardous agents in workplace; the unqualified rate of noise intensity was 14.3%-28.3%, reaching intensity grade Ⅱ; the qualified rate of microbial indicators was 33.3%. The risk assessment results showed that the risk value Rg of occupational hazards in the main unit was 176.6, grade Ⅲ risk level, high risk degree, and the risk value Rg of occupational hazards in the auxiliary unit was 89.5, grade Ⅱ risk level, medium risk degree. The overall risk value I of occupational hazards in the selected propsed construction project was 153.3, grade Ⅲ risk level, high risk degree.
Conclusion Risk assessment method combined with literature analogy method are suitable for the pre-assessment of occupational hazards in waste-to-energy projects. The combination solves the problem of relying solely on analogy method to identify occupational hazards and their concentrations (intensities) without quantitative classification on risk levels of occupational hazards in target construction projects.