Abstract: At 9:30 a.m. on July 1, 1999, Employee #1 was using a propane-powered forklift to move 55 gallon drums of fruit concentrate inside a cold storage room. Employee #2, a lab technician, was pulling samples from a locker at the storage room's entrance. By 11:00 a.m. both employees reported experiencing headaches, dizziness, and nausea. Employee #2 left the building to get fresh air, but Employee #1 continued working. At approximately 11:30 a.m., he was found slumped over the forklift's controls and EMS was called. Both Employees #1 and #2 were taken to Providence Hospital in Yakima, WA, and then to Kadlec Hospital in Richland, WA, where they underwent treatment in a hyperbaric chamber for carbon monoxide poisoning. A wall-mounted carbon monoxide monitor/alarm in the work area was not visible and had been unplugged from the wall socket.