Abstract: On July 28, 2010, a carnival ride mechanic was working in California for Butler Amusements, Inc., which was based in Beaverton, OR. He had determined earlier in the day that he would need to return later to the "Dragon Wagon," a children's roller coaster ride, for maintenance. Upon returning to the ride, he waved to the ride's operator and entered the area in the middle of the track via a portable fence. The ride was still in operation when the mechanic arrived, so he waited in the center area until the ride stopped. When the ride stopped, he walked up to one of the cars and bent down to look for a grease fitting at the base of the car adjacent to the track. Meanwhile, the ride's operator filled the cars with customers. As the mechanic placed his head between the track and bottom of the car, the ride's operator, who was not aware of the mechanic's location, started the ride. The ride moved forward, and the mechanic was hit in the head by a car. Then his head struck the track. When the mechanic stepped back from the ride, the operator saw him and stopped the ride. Emergency personnel arrived and transported the employee to UC Davis Medical Center in Sacramento. Though the employee sustained a fracture to the left side of his head, no surgery was performed. His right eye was severely swollen as well. He was released from the hospital several days later.