America's most dangerous jobs

• Fatality rate per 100,000 workers: 22.1
• Median wage: $37,770

Trucking is a tough job and drivers face tremendous pressure to get freight delivered on time. Despite rules requiring rest stops, many drivers are greatly fatigued. Indeed, 48% of truckers reported falling asleep at the wheel at least once in the previous 12 months, according to a 2005 survey by the Federal Motor Carrier Safety Administration.

Conditions haven't improved much since, said Henry Jasny, vice president of Advocates for Highway and Auto Safety. Although rest stops of 30 minutes are required after eight hours of driving, that's not nearly long enough, he said. Once they're back on the road an hour, drivers feel just as tired as before the break, he said.

Some truckers also falsify logbooks, with a fake set they call a "comic book" to show law enforcement officers that they've complied with the rules -- and a real one for their dispatchers, said Jasny.

Meanwhile, the fracking boom has introduced a new danger, he said. More heavy rigs now travel on narrow, rural two-laners that were never engineered to handle large trucks.

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