Abstract: At approximately 6:15 p.m. on January 21, 1999, Employee #1, a swamper at a gas pipeline construction site in Reserve, LA, was assisting her husband, who was operating a leased 30-ton Caterpillar bulldozer, model D6HLGF, serial #5HF5609. As the crew worked to backfill dirt around a ditch and in several holes at the site, the assistant superintendent asked Employee #1 to tell her husband that he was needed for a job at the other side of the site. There were two other trackhoes engaged in dirt work within approximately 100 ft. After telling her coworker/husband, Employee #1 began to move away when, for some reason, she walked behind the rear of the dozer. A nearby equipment operator saw Employee #1 in the danger zone, but was unable to stop the dozer until its right track had backed over her. She was killed instantly. Employee #1 had recently married the dozer operator after they were experienced employees who had worked for several companies in pipeline construction. The bulldozer had an operational back-up alarm, but it was not audible above the ambient noise; none of the witnesses later interviewed heard the alarm. At the time of the accident, it was getting dark, it would have been difficult to see someone on the ground near the machine. Employee #1 was not wearing a reflectorized vest. There were lights on the front of the dozer but none on the rear. The work day had started at approximately 7:00 a.m.