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Mechanic Crushed Underneath Four-ton Wood Chipping Machine

New Jersey Case Report: 12NJ024
Release Date: August 27, 2013

The following report is the product of our Cooperative State partner and is presented here in its original unedited form from the state. The findings and conclusions in this report are those of the individual Cooperative State partner and do not necessarily reflect the views or policy of the National Institute for Occupational Safety and Health.


A 54-year-old male mechanic at a tree trimming and removal company died after being crushed underneath an 8,000-pound wood chipping machine at a maintenance yard. On the day of the incident, the decedent and another worker were attempting to change the brakes on the wood chipper. They were using a telescopic hydraulic jack to lift the chipper in order to remove the wheels. After one side of the wood chipper was lifted, a single jack stand (rated for three-tons, used in a pair) was placed under that side. The decedent went underneath the machine attempting to properly position the hydraulic jack on the axle to lift the other side. The jack slipped, the jack stand broke, and the wood chipper fell on top of the decedent, killing him.

Mechanic Crushed Underneath Four-ton Wood Chipping Machine [PDF 1.12 MB]