The Control of Hazardous Energy (Lockout/Tagout), 29 CFR 1910.147, standard was promulgated on September 1, 1989, Federal Register, Volume 54, No. 169 (pages 36644-36690), and was effective January 2, 1990, as announced Federal Register, Volume 54, No. 213, November 6, 1989 (page 46610).

Employees servicing or maintaining machines or equipment may be exposed to serious physical harm or death if hazardous energy is not properly controlled. Craft workers, machine operators, and laborers are among the three million workers who service equipment and face the greatest risk. Compliance with the lockout/tagout standard prevents an estimated 120 fatalities and 50,000 injuries each year. Workers injured on the job from exposure to hazardous energy lose an average of 24 workdays for recuperation.