If you’re a business owner or a salaried employee, the long Labor Day weekend is a chance to kick back and relax before heading into the busy fall business season. If you’re an hourly employee — and more than half of all workers are, according to the U.S. Census Bureau — you might not have that luxury, particularly if you’re a low-level worker involuntarily working part time.

These are the workers who are at the highest risk of living on the edge of insolvency and falling through what limited safety net is available to them, researchers report.

They are especially susceptible to reduced, irregular and fluctuating hours, according to a new study by researchers at the School of Social Service Administration (SSA) at the University of Chicago. This is especially true for those workers classified as “involuntary part-time workers,” a term the Census Bureau uses for those who work less than 35 hours a week because they can’t find a full-time job or who work reduced hours because of “slack demand.”

As of November 2009, 9.2 million workers fell into that category, the highest level in recorded history. Though the recession has become the fall guy for every economic ill, this trend toward the “part-timing” of the American hourly worker has been under way for 30 years, says Susan Lambert, an associate professor at SSA.

"The recession is just highlighting changes in employment that have been going on for 30 years,” she told BusinessNewsDaily. “Employers have found other ways to temp jobs without hiring temp workers.”

Business and current management practices, particularly the emphasis on the short term, must shoulder partial responsibility for solving the problem, said Lambert,  as regulatory agencies are often reticent to make sweeping changes.

This article was provided by BusinessNewsDaily, a sister site to LiveScience.