Inspection Detail

Inspection: 304960792 - Cmi Terex Corporation

Inspection Information - Office: Oklahoma City Area Office

Investigation Summary

On December 12, 2001, four employees were completing the assembly of an asphalt plant loading and holding silo with the addition of accessories. Employee #1 was working in the discharge end in a confined area installing hose brackets. The area was the enclosed bottom of the silo and contained the discharge cone base with a pair of clam doors, a false bottom with a safety gate and man way completing the enclosure. The silo was lying horizontally, and the 3-foot by 3-foot safety gate opened for access. Employee #1 was arc welding and using a torch cutter on the hose brackets. Employee #2 and another employee were working on the silo top with the four employees supporting the other three with material and tools. Employee #1 was welding and cutting, which generated smoke. Instead of obtaining available mechanical ventilation equipment, Employee #1 disassembled the cutting torch and turned the oxygen on to vent the space. Then, all four employees went on a 15-minute break. Employee #1 and Employee #2 with the third employee returned to the silo bottom to weld the brackets. Employees #1 and #2 entered the silo bottom with the third employee just outside the safety gate. An arc was struck and a flash fire ensued. The clothing of Employee #1 and Employee #2 caught fire with both receiving severe burns. Employee #1 died about two weeks after the fire. Employee #1's action of ventilating the space with oxygen and the subsequent use of the arc welder caused the accident. Their employer failed to provide adequate training on welding/cutting in confined spaces, ventilation methods, hazards of ventilating with oxygen, and the inconsistent use of the available mechanical ventilation equipment. Employee #2 was hospitalized to treat his burns.

Keywords: BURN, CLOTHING, OXYGEN, VENTILATION, CONFINED SPACE, FIRE, WELDER, ARC WELDING, ASPHALT, SILO