Abstract: At approximately 11:30 a.m. on April 27, 2007, Employee #1 was working from an aerial lift, JLG Model Number 400S, Serial Number 30079117, approximately 21 feet above ground, welding steel bracing under the ceiling of a commercial building under construction. A coworker noticed that Employee #1 seemed to be not moving and blue in the face. Employee #1 was lowered to the ground and cardio-pulmonary resuscitation started but was unsuccessful. Employee #1 was pronounced dead at the scene, apparently due to being caught between the aerial lift and a brace. The aerial lift was later tested and problems were identified with the control stick which controlled upward movement of the boom. The control stick would not self-center or stop movement of the boom when released slowly as required by the manufacturer. Examination of the control stick found that hardened and compacted granular material built up on the centering ring and spring prevented the control stick from centering. There was also an absence of grease or lubricant on the centering ring and spring. Once the granular material was removed, the control stick functioned properly and self centered.