Crane Accident May have Been Caused by Faulty Strap

A crane collapse that occurred Saturday, March 15, may have been caused by a faulty strap made of nylon. The accident has claimed the lives of seven people and has damaged over 300 apartments in 17 buildings. The yellow nylon sling was used to hoist a six-ton piece of steel and may have broken under the extreme weight. Pictures from the scene show the ends of the strap frayed and ragged.

Investigators believe the accident occurred as workers were trying to install a massive square steel collar around the crane’s tower, at the 18th floor of the construction site. They were using a series of manual winches that appeared to have been hung from nylon slings attached to a higher portion of the tower. The collar was to have been attached to the building by steel struts to give the tower added stability.

But instead of this the collar, and the winches and slings, fell down the outside of the shaft and smashed into another collar which also broke free from the building. The collars then landed on a third collar near the base which destabilized the tower. The weight of the crane pulled the tower down onto several buildings, killing some and causing millions of dollars in damage.

The slings that were used normally cost around $50 and are supposed to be able to lift anywhere from moderate loads to several tons. But experts warned that if the slings become damaged or worn their strength is greatly diminished. Steven R. Dewey, president of a company that makes construction slings, said that slings generally fail only when they are cut or damaged, possibly from a previous lift. When investigators arrived on the scene the frayed straps immediately caused concern.

Officials in New York said that it was much too early to determine the cause of the accident or say why the slings broke but they are continuing to investigate.