Abstract: At approximately 4:30 p.m. on March 13, 2007, Employee #1 was working for the Granite Rock Co., a firm that manufactured asphalt and tar paving mixtures and blocks, in San Jose, CA. He was a truck driver, and he operated a mixer truck. He was training a new employee on how to clean the truck correctly, when another truck driver, in a rush, asked him to hurry things up. Employee #1 requested the trainee to tell the other truck driver that they would be done in just a minute. He then requested the trainee to raise the truck's "booster," the two auxiliary wheels at the rear of truck. Employee #1, not paying attention, continued to remove debris from the rear of the truck, leaving his hand leaning on the rear of truck. The rising booster caught his right thumb, peeling back a portion of skin and pulling off the thumb nail. Employee #1 yelled to the trainee to lower the booster and then called for help from another employee standing near by. The firm's dispatcher was notified and immediately called emergency medical technicians. An emergency crew arrived within five minutes with fire department equipment and an ambulance. The ambulance transferred Employee #1 to the Regional Medical Center of San Jose, where his injuries were examined. A doctor who was a skin graft specialist was able to find the nail bed, and a small portion of thumb bone was removed. Employee #1 was advised that thumb movement would eventually be restored.