Abstract: On February 24, 2003, Employee #1 was operating a Caterpillar Scraper (Model Number 657-B) to move dirt from one part of the construction site to another. The scraper was equipped with an open cab with roll-over protection and a seat belt. There were several similar scrapers operating in the area. Another employee was operating a bulldozer (Model Number D9N) in the near vicinity. After dumping a load of dirt, Employee #1 was driving the scraper back to the pickup point when he got hit in the head above his right ear. He got knocked down and hit his forehead on the steering wheel. Employee #1 asked another employee, who was driving another scraper ahead of him, to pull over and stop. Employee #1 was holding the right side of his head and told the employee that something hit him, but he did not know what it was. The foreman came over treated Employee #1's wound. Employee #1 drove himself to the Hoag Memorial Hospital in Newport Beach where he was treated for a depressed fracture in the skull. From the nature of the wound and the dirt around the wound area, the foreman and the other employee concluded that Employee #1 was hit by a flying rock which may have been kicked up by the bulldozer operating nearby. Employee #1 was not wearing a hard hat at the time of the accident. Employee #1 required two steel plates installed in his skull and was hospitalized for nine days.