Abstract: Employee #1, age 20, was working in the open basement level of a 23-story high rise structure. A Pecco 400 tower crane was hoisting 350 lb, 24 in. square by 29 in. high electronic pulse filter units from the first floor level to the penthouse level of the building. As the load reached the 24th level, it came up underneath a 3 1/2 ft protruding ledge and was thrown from its slings. Employee #1 was working 60 ft from the load's initial pick up point when he was struck by the falling load. The crane operator, who was picking in the blind, was relying on radio communication from the signalman to maintain safe clearance.