Compiled By Tonya Vinas Manufacturers are among several groups that are relying on mandatory overtime to keep staffing costs down, according to a recent study on forced overtime. Researchers Lonnie Golden, associate professor of economics at Pennsylvania State University, University Park, and Helene Jorgensen, research associate at the Center for Economic and Policy Research, Washington, D.C., conducted the study. They found the agriculture, mining, manufacturing, transportation and communication industries have 25% or more of their workforces working overtime on a regular basis. According to the researchers, overtime can lead to "substandard work and considerable strain on family balancing." They say stress- and fatigue-related problems caused by mandatory overtime cost U.S. businesses $150 billion to $300 billion annually. "Workers who put in the kind of long hours that go along with overtime often get less sleep, which can lead to an increase in workplace accidents and injuries," Golden says.