America's most dangerous jobs

• Fatality rate per 100,000 workers: 37
• Median wage: $44,540

Falls are one of the most common causes of death for ironworkers. But they also risk injuries from steel beam or reinforced concrete wall collapses, "struck-by" injuries from falling or swinging objects, and contact with live electrical lines.

New work rules have slashed injuries from one particular danger, according to Steve Rank, executive director of safety & health for Ironworkers International union. The rules now require vertical beams to be anchored with four bolts instead of two, so beams are less likely to work loose and crash.

"I can't tell you how much that has helped," he said. "Accidents have plummeted."

His next crusade is to get OSHA to pass more stringent rules governing reinforced concrete walls, which, he said, have been collapsing and killing too many ironworkers. The walls, which can be 60 feet tall, can topple and cause devastating injuries.

NEXT: Sanitation workers