Abstract: At 5:00 a.m. on December 2, 2007, Employee #1, a tank cleaning technician for Grand Isle Shipyard, was spraying wash water in the port side holding tank of the utility ship "Terry Bordelon". Employee #1 also had an attendant perched above him at the top of the entrance to the tank, which is the deck of the boat. Employee #1, in the portside tank, signaled to his attendant that he needed a rag to wipe the glass on his full facepiece, airline respirator. The attendant got a rag and tossed it down to Employee #1, who began to climb up the tank ladder to exit the tank. When Employee #1 reached the top rung, he fell back down into the tank, displacing his respirator and exposing him to the tank atmosphere. His attendant called for help from the site supervisor, and a rescue tripod was acquired a short distance away from the entrance to the port side tank. The other starboard side cleaning technician was summoned to enter the port side tank for rescue. While the port side attendant and site supervisor were obtaining the tripod, the other starboard side attendant (Employee #2), working at the starboard side tank, on the adjacent job, entered the portside tank to reach Employee #1 lying on the tank floor. The cleaning tech from the starboard side tank entered into the port side tank to attach the tripod line to Employee #1's harness. When he went down into the tank, he observed the starboard side attendant (Employee #2) laying unconscious without an airline respirator. The injured cleaning tech was immediately retrieved. Emergency Medical Services had cut the harness from Employee #1, rendering it unusable for Employee #2. Another harness had to be obtained from the ships crew. By the time the starboard side attendant (Employee #2) had been retrieved, he was unconscious and could not be revived and shortly died. Employee #1 died a few days later from the injuries he sustained from inhaling hydrogen sulfide gas.