What does a Job-Exposure Matrix (JEM) help you do?

• A. Set regulatory limits
• B. Average all exposures across all workers
• C. Link job tasks to typical exposure ranges to guide monitoring and control priorities
• D. Determine exact concentrations for each worker

Answer: (C)

A Job-Exposure Matrix helps you translate different job tasks into typical exposure ranges so you can prioritize monitoring and control efforts. By linking each job title or task to a known or estimated exposure level, you get a practical overview of where workers are most at risk and where monitoring resources should be focused. This isn’t about setting regulatory limits, nor about averaging exposures for all workers, nor about determining exact concentrations for individuals. Instead, it provides a structured way to identify which roles are likely to have higher exposures and to guide where to sample first and which controls to implement. For example, a JEM might show that welding tasks commonly fall into a higher exposure category for metal fumes, guiding you to target respirator use, ventilation improvements, or additional monitoring for those workers, while routine office tasks stay in a low category. The matrix is a planning and prioritization tool, not a final measurement for every person.