Abstract: At approximately 9:00 a.m. on July 27, 2000, Employee #1, of Redding Roofing Supply, Inc., was on a truck, moving bundles of tiles, three at a time, onto a conveyor. The total weight of the tiles was between 24 and 27 lb. Employee #1 had been doing this for between 30 and 45 minutes when he experienced severe pain in his lower back. He was transported to the hospital, where he was treated and released after about three hours. Approximately one week earlier, Employee #1 was loading a roof at another location. He was situated on a lower roof and a coworker would bring over a set of three tiles that weighed between 15 and 18 lb. The coworker would release the tiles, which dropped approximately 2 ft before Employee #1 caught them. The job lasted 20 to 25 minutes and Employee #1 noticed a pain in his back by the time it was through.