Case Report from OSHA files
- A three-man crew was using an improvised suspension scaffold to paint the interior of a 68-foot-tall, 32-foot-diameter water tank. The scaffold
consisted of an aluminum ladder used as a platform, and secured to steel "stirrups" made of steel bar stock bent into a box shape and
attached to each end of the ladder. Wire cables from each stirrup ran to a common tie-off point. A cable from this common tie-off was rigged to a
block-and-tackle used from ground level to raise and lower the platform. The block-and-tackle supporting the system was secured to a vertical steel pipe
on top of the tank by a cable, which was fashioned into a loop by U-bolting the dead ends of a piece of wire rope.
The victim had been painting from one end of this scaffold while wearing a safety belt and lanyard attached to an independent lifeline. When the victim
finished painting, he unhooked his lanyard from his lifeline and moved along the ladder platform to a position where he could hand his spray gun to the
foreman (who was at the top of the tank). As the foreman took the spray gun, he heard a "pop" and saw the scaffold and the victim fall 65 feet
to the floor of the tank.
Investigation of the incident revealed that the two U-bolts on the loop of cable supporting the block-and-tackle had loosened enough to allow the cable
ends to slip through, causing the scaffold to fall. This particular rig had been used without incident every day for two week preceding this fatal fall.
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