Abstract: At approximately 4:30 p.m. on May 11, 2005, Employee #1 was operating a portable angle grinder, grinding plastic-resin parts on sinks and bathtubs in order to smooth the edges. The grinder being used by Employee #1 had a particular button that was to be kept depressed in order to operate. Releasing the button automatically stopped the grinder wheel from revolving. Employee #1 placed the grinder on a surface and released the operating button after grinding a wall. Employee #1 observed the grinder wheel continuously revolving without him depressing the operating button. Employee #1 observed the operating button was jammed in the depressed position. He then tapped the button a few times in an attempt to get the button to pop up. Employee #1 did not unplug the grinder before attempting this. Employee #1's tapping on the grinder caused the grinder to fall off the surface toward him. Employee #1 attempted to dodge the falling grinder but it made contact with his left lower arm. He sustained lacerations to his lower left arm, including lacerations to arteries and tendons, which required hospitalization.