Over the past three decades, Jim Wiethorn has investigated hundreds of crane accidents and generated a mountain of data on what causes lifting machines to fail. Instead of hoarding that information, he is providing it to the industry to help jobsites become safer.


Chairman and principal engineer at Haag Engineering Co., Wiethorn this past summer published his Sugar Land, Texas-based crane team's analysis of more than 500 investigations in a book, titled "Crane Accidents: A Study of Causes and Trends To Create a Safer Work Environment," which is available on the company's website HaagEducation.com for $249.


Haag's database reveals some surprising facts. One revelation is that "other field personnel," or workers not involved in a lift, are killed more often than any other workers, including those performing the lift.

"That shocked me," says Wiethorn of the findings. The results are a "frightening" reminder to "get people the hell out of the way," he adds.

Some accidents are the result of poor management decisions that collapse like a line of dominoes. Others underscore the difficulty of behavioral change, such as when site workers disregard the yellow tape and walk into the lifting zone. "I cannot tell you how many accidents I've had where people ignore it and set up a plan shack right in the middle of the field where they are in the laydown area," he says. The book emphasizes teamwork and shared responsibility and warns that small, repetitive lifts have the potential for danger because they attract far less scrutiny than critical picks.

Wiethorn, 64, learned how to operate cranes at a young age, as he grew up in a third-generation family construction business. He originally set out to become a dentist but quickly changed his mind. "I woke up on December 18, 1971, in a cold sweat, thinking that I'm going to be looking down somebody's throat for the rest of my life," he says. Wiethorn earned degrees in architectural engineering from the University of Texas at Austin and worked as a project engineer for a structural engineering firm. In 1987, he joined Haag, which claims to be the world's oldest forensic engineering company, founded in 1924.

As an expert witness who has given more than 200 depositions, publishing the book could end up biting him in court, some engineers say. But Wiethorn says he is confident in his findings. "We are interpreting data," he says. "We're not throwing out opinions."