With the recovery of three more bodies, seven people – six construction workers and a woman visiting for St. Patrick’s Day – were killed in Saturday’s crane collapse on East 51stStreet in Manhattan. A preliminary city investigation found that the crane toppled after a steel collar used to tie it to the side of the building fell as workers attempted to install it.
Officials are investigating whether a series of hoists and nylon straps used to hold the collar temporarily in place were strong enough to sustain its 12,000 pound weight, particularly since a ripped nylon strap was found attached to the collar. The collar, made of two U-shaped pieces of steel joined together, was to be secured to the tower and then tied by steel struts to the building.
When the collar fell it slammed into another collar that was a major anchor securing the tower crane already in place at the ninth floor, shearing it from the struts that held it to the building and carrying it down to smash into a third collar at the third floor. The elimination of the lower support the counter-weights at the top of the crane’s tower caused it to fall.
Patricia J. Lancaster, the building’s commissioner, said the position of the cab, with its approximately 40 tons of counterbalances, might have contributed to the disaster by pointing south, thereby pulling the crane away from the building. 24 people were injured in the accident. Buildings forensic engineers have confirmed at least 7 buildings sustained damage during the accident. 17 buildings were vacated.
The four victims initially recovered were Wayne Bleidner, Anthony C. Mazza, Aaron Stephens, and Brad Cohen.
It was also announced that Joy Contractors, Inc. was the company hired to operate the crane. There were 128 construction-related injuries in 2007, up from 116 in 2006, according to Buildings Department statistics. The number of construction fatalities fell from 18 in 2006 to 12 in 2007. There were at least five fatalities this year before the crane collapse.