The number of workers who died on the job fell by 17 percent last year to the lowest level in nearly two decades, as workers logged fewer hours during the recession, the Labor Department said Thursday.

The 4,340 workplace fatalities recorded in 2009 was the smallest total since the Bureau of Labor Statistics first began tracking the data in 1992. It’s the second straight year that fatal work injuries have reached a historic low, following a 10 percent drop in 2008.
High unemployment and layoffs in more dangerous industries such as  construction played a major role in the decline, the agency said. The construction unemployment rate is 17.3 percent, nearly double the overall jobless rate of 9.5 percent.

Workers on average logged 6 percent fewer hours last year than in 2008. Employees in construction worked 17 percent fewer hours in 2009 than the previous year.

Labor Secretary Hilda Solis called the decline encouraging and pledged to continue her agency’s stepped-up enforcement of workplace safety laws.

“As the economy regains strength and more people re-enter the workforce, the Department of Labor will remain vigilant to ensure America’s workers are kept safe while they earn a paycheck,” Solis said.

Workplace suicides declined 10 percent, to 237, after reaching a historic high in 2008. But that count is still the second-highest recorded since the agency began tracking workplace deaths.

For the second straight year, commercial fishing was the deadliest occupation in the country, with a fatality rate about 60 times higher than the average rate for all workers.

One of the few sectors where the fatality rate rose was in building and grounds maintenance, where the number of deaths increased 6 percent.

The report is based on preliminary numbers. A final report is scheduled to be released next year.

In other findings:

– Transportation incidents, which accounted for nearly 40 percent of all work fatalities last year, fell 21 percent from 2008.

– Fatalities among black workers declined 24 percent. Black employees also saw a larger decline in the number of hours worked than whites or Hispanics.

– Workplace homicides declined 1 percent, to 521 cases. That is nearly half the all-time high of 1,080 homicides recorded in 1994.