Abstract: At approximately 1:20 p.m. on June 7, 2002, Employee #1, a foreman and operator for Souza Construction Company of San Luis Obispo, CA, was checking the grade on a road under construction. A coworker was driving a water truck approximately 300 ft away from him. The coworker's job was to keep the road dust down. He saw some dust blow up and started backing up toward the spot at the speed between 5 and 8 mph. The coworker made a turn to the left to reach the dusty area and then felt as though he went over a rock. He drove forward, felt the bump again, and then stopped to check what was in the roadway. The coworker had run back and forth over Employee #1, who died as a result of his injuries. The back-up alarm was tested under the same conditions a few days after the accident; it was determined that the alarm could be heard over the noise in the area only within 75 ft of the truck.