Ep 208 - The 3 AM TRIR Frustration (Evaluating ASOHMS vs. Z10)

In this #StudyFinds episode of #ProveItPod, Dr. Matt Law battles post-conference road fatigue to tackle a brand new case study from the International Journal of Construction Management. The study reviews the implementation of the Army Safety and Occupational Health Management System (ASOHMS) within a USACE district.

While the researchers found a correlation between the system's implementation and a reduction in contractor incident rates, the episode dives deep into the statistical methodology. We compare ASOHMS to ANSI/ASSP Z10 and ISO 45001, break down the double-edged sword of "rolling averages," and ask a tough question: If landmark research proves that TRIR is statistically invalid and driven by random variance, can we really use it to prove our complex management systems are working?

References:

American Society of Safety Professionals. (2019). Occupational health and safety management systems (ANSI/ASSP Z10.0-2019).

Hallowell, M., Quashne, M., Salas, R., Jones, M., MacLean, B., & Quinn, E. (2021). The statistical invalidity of TRIR as a measure of safety performance. Professional Safety, 66(4), 28–34.

Moskowitz, J. M., & McCranie, J. B. (2025). Investigating the impact of army safety and occupational health management system implementation on safety performance indices: case study of a U.S. Army Corps of Engineers district. International Journal of Construction Management, 1–17. https://doi.org/10.1080/15623599.2025.2537722

U.S. Army Corps of Engineers. (2024). Safety and health requirements manual (EM 385-1-1).