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You might wonder how the investigative process of Failure Analysis applies to back injury liability. We find that it is not a remote connection, but a very direct one. We would like to use the example of the following case to illustrate the point of how the Failure Analysis process helped assess liability for a very large personal injury settlement.



We were retained by a lawyer to assist in determining the cause of an extremely serious back injury that had resulted in permanent disability for his client. The client was a man in his mid thirties, who was experienced in moving heavy equipment from location to location. In this instance the equipment involved was a large compressor used in making artificial ice for a skating arena. It was being moved from Toronto to Hamilton, Ontario. In the process it was loaded on to a box truck using a fork lift. Two men, including the driver of the truck accompanied the unit to its destination in Hamilton. There was no fork lift at the dock where the compressor was to be unloaded. The supervisor therefore instructed two additional men to help unload the compressor using a hand dolly. As the compressor was being moved toward the back edge of the truck it became unbalanced. It tipped towards the dock, where two of the workers were guiding its movement. One of them was unable to move out of the way as he was trapped in the corner of the unloading area. There was a wall on one side and the second worker on the other. He was facing the compressor with his hands at chest height pushing back against it. The second worker had leaped out of the way. He held the compressor in a balanced position until the others were able to move it back onto the bed of the truck. The client felt a slight twinge in his back at the time but thought nothing of it. When he awoke the next morning his back was quite sore, so he took the day off and rested. From that point on, things went down hill. His back became extremely sore and he could only do light work.

Over the next five years he had two major back operations including spinal fusion. He was extremely limited in his physical movement and had a substantial reduction in earning capability, quality of life and life expectancy. The relationship with his wife and children suffered as well.

During our initial meeting when the background information was obtained it was determined that the compressor was still available, the site had not changed and detailed information on the truck was available.

As is done with most large Failure Analysis cases, Walters Consulting assembled a team of experts including a mechanical engineer, experienced in Failure Analysis; and industrial engineer, experienced in Human Factors (Ergonomics) and a seasoned expert to appear as a witness in court if this should be necessary.


The Investigation

The Walters team examined the compressor, took detailed measurements, calculated the centre of gravity using a complex iterative process and determined an accurate weight. The site was visited, measured and a scale drawing produced. The point at which the compressor would tip was calculated after determining the measurements of the truck.


Accident Reconstruction

The accident was reconstructed using scale drawings and the height and weight of the human involved determined. A computer program was used to simulate and calculate the forces that would be acting on the L4, L5 section of the spine where the injuries occurred.


Testing and Analysis of Results

The forces acting on the human were tested and compared with allowable limits before injures would occur. It was determined that he forces were beyond human tolerance, and that injuries were inevitable. This involved research with the U.S. National Institute of Occupational Safety and Health.


Expert Witnessing

The findings were presented to a court using demonstrative evidence such as the schematics accompanying this article.

The court made an award of $625,000 under the Occupational Health and Safety Act with the employer liable for the settlement. The settlement was significantly higher than the one that was originally discussed.

The entire investigative process was the same as the one used in Failure Analysis.

The information contained in this web site is intended for marketing purposes only. It is not all-inclusive, and does not fully describe the many and varied services that the company provides, nor does it completely describe the education, training, skills, or expertise of our staff.


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