As machine technology advances, the energy sources driving machinery have become more powerful and sophisticated. In turn, service and maintenance tasks have gotten more demanding, complex and often more dangerous.
While OSHA's lockout/tagout standard has been in effect since 1989, hazardous energy release incidents continue to be a problem. The Bureau of Labor Statistics reported 189 workplace deaths caused by workers being caught in machinery in 1997, a 29 percent increase from the previous year. More than half of these fatalities happened while workers were performing service- or maintenance-related tasks.