Heinrich's theories challenged

In the 1930's, William Herbert Heinrich, an employee working for Traveler's Insurance Company, published groundbreaking theories about safety and health in the workplace. One such theory became known as Heinrich's Law: that in a workplace, for every accident that causes a major injury, there are 29 accidents that cause minor injuries and 300 accidents that cause no injuries. Because many accidents share common root causes, addressing more commonplace accidents that cause no injuries can prevent accidents that cause injuries.

Heinrich's theories, in particular the one I mention above, are considered sacrosanct. Until now...

Fred Manuele is an accomplished safety professional and currently serves as president of Hazards Limited, a consulting firm. Mr. Manuele published a recent article in the ASSE periodical Professional Safety challenging the validity of Heinrich's Law. The challenge specifically targets this premise - focusing on incident frequency reduction will equivalently achieve severity reduction. What Mr. Manuele found is that if you manage the small incidents effectively, the small incident rate improves, but the major accident rate stays the same, or even slightly increases.

Click here to read Mr. Manuele's compelling article: http://www.asse.org/professionalsafety/pastissues/056/10/052_061_F2Manuele_1011Z.pdf

At Predictive Solutions, we have come to the same conclusions as Mr. Manuele. Addressing low to medium severity findings such as housekeeping, administrative items, and PPE does nothing to address serious or life threatening observations such as fall protection hazards or excavations. In fact, we find that most inspectors tend to shy away from or fail to document higher severity observations altogether for many reasons. It is very difficult to manage your greatest risks when this continues to occur.

Ideally, observations on behaviors and conditions, including unsafe observations, should be gathered freely and without judgement. In fact, I consider these consequence free - no accident has occurred and they provide an opportunity to both predict and prevent future occurrences. Once this is done, an organization can then prioritize where resources and actions should be focused - namely at the highest severity findings in conjunction with the frequency of occurrences. Once action has been taken, future observations can then validate the effectiveness of the intervention. This methodology allows for both continuous improvement and sustainability.


Cary Usrey

Written by Cary Usrey

Cary Usrey has been at Predictive Solutions since March 2007. As a Process Improvement Leader, Cary is responsible for implementing best practices for customers seeking to prevent worker injuries. He coaches customers through an assessment, goal-setting, and goal measurement process that is designed to maximize safety improvement and widespread organizational engagement, from the field to leadership. Cary started his career in the U.S. Navy's Nuclear Power Program. After leaving the Navy, he served as the Environmental, Health and Safety Compliance Director at Adirondack Resource Recovery Associates, a waste-to-energy power plant in upstate New York, where he was employed for over twelve years. Following this, Cary took a position with Turner Construction, where he served as the Business Unit Safety Director for the upstate New York office for approximately three years. Cary has graduated with his Associate's Degree in Occupational Safety and Health from Trinidad State Junior College in Colorado, is a member of the Central FL chapter of the ASSE, and has served on the Board of Directors for the VPPPA (Region II).

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