This morning’s construction crane collapse in New York City, following a similar event there on March 15, brings to light the inherent dangers involved in industrial construction. Today’s event is at least the fourth fatal crane accident in the U.S. this year, with others in Miami and near Kansas City. More than 5,000 work-related fatalities are reported every year in the construction industry—the largest number for any industry. About 20% of these fatalities are related to heavy equipment and construction accidents.
The global building boom has resulted in a maze of construction or tower cranes in nearly every major city. Shanghai was once said to have about half of all the tower cranes in the world during the peak of its building boom a couple of years ago—and it had its share of crane accidents as well. The erection of these cranes is an inherently hazardous operation, with many cities recommending suspension of nearby activities during erection and the creation of exclusion zones around the operational area. At a minimum, each crane must be inspected and tested. Following the March 15th crane collapse in NYC, city officials increased their inspection protocols with inspectors required to be present every time a crane is erected, “jumped”, or dismantled; written protocols from engineers for these operations; and engineering inspections during each erection.
Research into the reasons for crane accidents include broken parts or cables on the crane, failure of braking mechanisms, improper maintenance, hydraulic failures, severe weather events (wind), insufficient design, and operator error. As in most construction equipment, the designs are generally made with safety load factors of between 4 and 10, depending upon the particular component. Crane load capacities are similarly rated by the size and weight of the crane, and the angle and position of the boom.
The inherently hazardous operation of tower cranes and the generally fatal or near-fatal injuries resulting from accidents make them the continuing focus of attention to the public and the media. Changes in their design, operation, inspection, and oversight are most often made after accidents like those in NYC. Mayor Bloomberg has already said that this morning’s accident is “unacceptable and intolerable.” We most assuredly must find the cause of this accident and make appropriate corrections to ensure it’s not repeated. However, the current construction frenzy, a continuing weakening of our overall infrastructure, and the demand for continued economic growth will not make this the last fatal accident to catch our attention.
