Wind Turbine Hazards Multiply
Taller, larger turbines are making the job more dangerous for maintenance crews, a Safety 2015 speaker explained June 8.
The hazards faced by workers performing maintenance work on wind turbines are increasing as the turbines multiply and grow larger, Craig Bierl, an assistant vice president and senior energy risk specialist for the Chubb Group of Insurance Companies, explained during his June 8 session at ASSE's Safety 2015 in Dallas. Many of the hazards are garden variety, he said, but workers encounter almost all of them -- falls, confined spaces, fire hazards, lockout/tagout, first aid, electrical hazards, machine guarding, and arc flash safety -- 300 feet above the ground, making rescue or descent difficult.
The industry has seen explosive growth since 1999, and so have the turbines, which have increased by about 50 percent in height (they were 60-68 meters high a few years ago but now are 100-110 meters high) and by 96 percent in rotor diameter, he said, and annual installations are predicted to stay high through 2050.
While most turbine manufacturers recommend a minimum of 500 meters of clear space around a turbine, many now are sited close to schools, homes, and other important structures, Bierl explained.
He showed a photo from a nacelle fire and discussed some serious incidents, including a fire in a turbine's nacelle that resulted in two workers' deaths, a wind turbine destroyed by spinning too fast, and a worker who fell inside a turbine blade during maintenance work.
Newer turbines have climbing assist equipment or elevators installed -- and the latter can satisfy OSHA's requirement that rescue of an injured worker must occur within four minutes -- but climbing a ladder in an older model to its nacelle can take 30 minutes, he said. "Every time you climb, it's a hazard, no matter how good shape you're in."
"Anything you do in a hurry up there is going to increase your chance of an accident," he added. Bierl explained that most turbines have no fire protection systems installed, making pre-fire planning important for maintenance firms. Other key recommendations included these:
- De-energize; do not work on live equipment.
- Do a climber evaluation every time.
- Ensure a trained rescue team is available.
- Follow the two-worker rule: Every turbine maintenance job must have two workers, at minimum.
"One of the biggest things is tool drops," Bierl said during his presentation. "A lot of guys [are] getting hurt by tool drops."