Construction cranes inspected by operators, not government
"Our code is straightforward -- follow the manufacturer's instructions," OSHA says
Friday, April 04, 2008
TOM HALLMAN JR.
Tower cranes -- those massive cranes that, well, tower above high-rise buildings under construction -- have become such a part of Portland's skyline that people take their presence for granted.
Only when there's been an accident, as was the case last month in New York City and Florida and again in Florida on Thursday, do people glance skyward and wonder how the cranes work and whether they're safe.
About 25 cranes are operating at job sites around town, said Greg Bellcoff, territorial manager for Coast Crane Co., which rents cranes to customers from Alaska to Southern California.
Just take in the view from the Fremont Bridge: You'll see three within a few blocks of one another in the Pearl District.
Nearly all of the cranes in Portland are rentals, said Bellcoff, whose Seattle-based company has five tower cranes at Portland-area sites. Rental rates, depending on the height of the crane, run from $15,000 to $30,000 a month. A top-of-the-line tower crane, he said, costs more than $1.5 million.
What may surprise people is that no government agencies -- not city or state -- inspect the cranes. That's up to the manufacturer and the specially trained operators hired by construction companies to run the big rigs.
"Believe it or not, we can't keep up with the changes," said Mike Lulay, a technical specialist with Oregon's Occupational Safety and Health Division, the agency charged with crane safety. Manufacturers are constantly working to improve the load capacity and come up with new innovations.
"The advances on these machines come so quickly that we could never keep up with them from a point of view of imposing rules," Lulay said. "Our code is straightforward -- follow the manufacturer's instructions."
After a crane collapsed in New York, a check of Oregon records found no recent record of a crane accident here, said Melanie Mesaros, a state OSHA spokeswoman. "I went back 15 years and couldn't find anything," she said.
Crane manufacturers, crane operators and construction site superintendents work as a team to make sure the crane goes up safely and gets used the right way.
"There are three components for safety," Lulay said. "How it's designed, the operator and the riggers who hook up the loads. As long as the operator follows the manufacturer's rules and the riggers do what they're supposed to do, there won't be a problem. If people deviate from that handbook, we get heartburn."
Oregon has stricter rules than does the federal government, he said, specifically requiring that crane operators have extensive training and renew their training and safety card every three years. Those who come to Oregon from another state for a job must verify that they've had at least 1,500 hours of experience before being allowed to run a crane here.
The operators don't just get in the crane cab and go. They must inspect the equipment daily and look at the bolts that hold the tower sections in place.
Engineers design and approve the concrete footing poured for a crane's base, then the construction company brings in a team of specialists called steel erectors to assemble the crane at the job site.
"The crew has been doing this a long time," Bellcoff said. "They set up about 90 percent of all the cranes used around here. They know what they're doing. A licensed electrician hooks it all up, and then we do a load test for the machine."
The erector crew and an on-site manufacturer's representative certify every step of the process. Some contractors go as far as to bring in a third party to check all work before the crane is used. The paperwork is then displayed at the job site on what's called the "right-to-know board," the place where all permits are posted.
Nearly all tower cranes have a safety factor of 10 designed into the crane by engineers.
"If they design something to hold a load of 100 pounds and the safety factor is 10, they'll rate the crane's capacity as 10 pounds," Lulay said. "If they stay within rated capacity, a crane's not going to collapse."
But cranes lift large loads. A tower crane working in downtown Portland, for example, is rated to safely lift nearly 30,000 pounds. Computers on board can stop a load from moving if it senses problems.
Lulay said wind, more than weight, causes problems for tower cranes.
"If you think about it, it's like a big sail up there," he said. "Stick your hand out a car window and open up your fingers. You still get resistance. There's movement up there. The crane sways. I'm used to it. Years ago I was a high climber in the logging industry. When I'd cut the top of a tree, it would sway back and forth."
Bellcoff, though, has no interest in visiting a tower crane cab.
"I'm not a heights guy," he said. "I don't like it up there."
Tom Hallman Jr.: 503 221-8224; firstname.lastname@example.org