After further investigating the cause of collapse in Seattle’s tower crane back in April, officials have confirmed that the crane failed because “connecting pins were removed prematurely from the nearly 300-foot tower,” according to the Seattle Times. The error left the crane vulnerable when it was hit with a 45 mph gust of wind.
According to the article, the crew was not supposed to remove pins from the tower crane until it was attached to the assist crane that was disassembling it. However, crews had removed more than 50 pins from “the entire length of the structure,” Brian Haight, supervisor of the Washington Department of Labor & Industries (L&I), told the Seattle Times. This left only one pin in place just before the collapse.
L&I officials fined the Morrow Equipment (the crane supplier) $70,000. The department reported that it was a Morrow employee who failed to execute proper disassembly.
Two ironworkers were killed in the collapse, as well as two passersby on the street below.
Source: The Seattle Times