Abstract: Employee #1 was part of a five-man crew that was moving a Caterpillar 231D LC excavator from one side of a bridge to the other. The deck on the side of the bridge they were on had already been poured. On the other side, the deck was being prepared for a pour, and running along the centerline of the bridge were concrete Jersey barriers. Employee #1 and a coworker were n front of the machine, laying down 4 by 8 sheets of plywood so that the tracks of the excavator would not damage the new concrete lane. The two workers would lay down a sheet in front of each track; the excavator would move forward until the track reached the edge of the lead pieces of plywood, then stop. After it cleared two plywood sheets, coworkers at the rear of the machine would pick them up and slide them along the tops of the tracks to the workers in the front. Those workers would lay down a piece on each side and then get clear of the tracks so the excavator could advance again. There was very little distance between the excavator tracks and the barricades and railings: the clearance between the edges of the tracks and the rails ranged between 6 and 9 in., and there was less than 1 in. between the tracks and the barricades. Prior to starting the job, these narrow clearances had been specifically discussed and it was decided that several people should be involved so that no one would need to cross over to work both behind and in front of the excavator. Employee #1 was staying right next to the guardrail as the excavator track passed when he became caught between them. He suffered multiple fractures and soft tissue trauma, for which he was hospitalized.