Historically, the focus of industrial health and safety (H&S) has been on safety and accident avoidance with relatively less attention to long-term occupational health other than via health monitoring and surveillance. The difficulty is the multiple overlapping health consequences that are difficult to separate, measure, and attribute to a source. Furthermore, many health problems occur later, not immediately on exposure, and may be cumulative. Consequently, it is difficult to conclusively identify the cause. Workers may lack knowledge of long-term consequences, and thus not use protective systems effectively. Compounding this is the lack of instruments and methodologies to measure exposure to harm. Historically, the existing risk methodologies for calculating safety risk are based on the construct of consequence and likelihood. However, this may not be appropriate for health, especially for the long-term harm, as both the consequence and likelihood may be indeterminate. This paper develops an instrument to measure the health component of workplace H&S. This is achieved by adapting the established World Health Organization Disability Assessment Schedule (WHODAS) quality of life score to workplace health. Specifically, the method is to identify the likelihood of an exposure incident arising (as estimated by engineering technologists and H&S officers), followed by evaluation of the biological harm consequences. Those consequences are then scored by using the WHODAS 12-item inventory. The result is an assessment of the Diminished Quality of Life (DQL) associated with a workplace hazard. This may then be used to manage the minimization of harm, exposure monitoring, and the design of safe systems of work.