Semi-quantitative microbial risk assessment: a narrative review and proposed framework for health and safety practitioners

Background and Objective: Exposure to pathogenic bioaerosols presents a hazard to workers and the general population, as demonstrated during the COVID-19 pandemic. Few resources and tools are available for assessing transmission risk at the workplace and designating appropriate controls to reduce the risk of transmission, which is highlighted by the lack of available standards and regulations designed specifically for conducting workplace quantitative microbial risk assessments (QMRAs). Based on existing literature and tools, a flexible semi-quantitative microbial risk assessment (sQMRA) framework for health and safety (H&S) practitioners was developed to assess and manage occupational exposure to bioaerosols in the workplace.