Abstract: Employees were installing a manhole. One employee was operating a Model 350 Caterpillar Excavator to raise and lower the risers onto the manhole. Employee #1 was standing in the manhole, guiding the risers on top of each other. Employee #1 in the manhole gave the operator the signal to raise the wire ropes used to raise and lower the riser. The riser was secured to the wire rope by a pin in each leg of the sling. One pin was still in the riser and, as the riser was raised it slid forward, pinning Employee #1 between the riser and the wall of the manhole, which resulted in Employee #1's death.