Abstract: Employees #1 through #4 were standing 16 ft above the ground floor on an elevated walkway erecting a precast radius to a soffit concrete unit. One of the two suspension points of the 2,500 lb piece was supported by an overhead hammerhead tower crane. The other lift point was already transferred to a chain hoist just inside the east elevation of the building. While the unit was being rotated, the load hook of the chain hoist was subjected to a side pull. The safety latch of the hook was forced out of the hook and the load was detached, causing the unit to pendulum. The unit smashed the walkway and Employees #1 through #4 fell 16 feet. They sustained rib and elbow fractures. The accident was caused by a rigging failure and the use of an improper technique.