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Job exposure matrix for electric shock risks with their uncertainties.
Ximena P Vergara1, Heidi J Fischer2, Michael Yost3
1Electric Power Research Institute, Environment Sector, Palo Alto, CA 94304, USA. xvergara@epri.com.
Summary
This study updates the electric shock job exposure matrix (JEM) with quantitative measures for 501 occupations. New dimensions improve electric shock exposure estimates for epidemiologic research.
Area of Science:
- Occupational Health
- Environmental Epidemiology
- Risk Assessment
Background:
- Existing electric shock job exposure matrices (JEM) often provide qualitative or ordinal exposure levels.
- Accurate quantification of occupational electric shock exposure is crucial for epidemiological studies.
- Previous JEMs relied on limited data sources and expert judgment, necessitating an update.
Purpose of the Study:
- To develop an updated, quantitative electric shock job exposure matrix (JEM) for 501 occupational titles.
- To incorporate elicited exposure proportions and uncertainty intervals for more precise risk assessment.
- To evaluate the impact of exposure assignment cut points on epidemiological studies in the electric work environment.
Main Methods:
- Formal expert elicitation was used to gather data on occupational electric shock incidence.
- Three new quantitative dimensions were added: elicited median, 25th, and 75th percentiles of exposure.
- A relative interquartile range (rIQR) was constructed based on uncertainty intervals and medians.
Main Results:
- A consensus-based, quantitative JEM was developed for 501 occupational titles.
- The updated JEM provides median, 25th, and 75th percentile estimates for electric shock exposure.
- Overlapping exposure ranges highlight areas where knowledge about occupational electric shock is limited.
Conclusions:
- Novel methods enabled the transition from qualitative to quantitative exposure estimates in a population-based JEM.
- The updated JEM offers more consistent and refined exposure assessments for occupational health research.
- Further research is needed to refine estimates in categories with overlapping exposure ranges.
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