The practice of de-energizing equipment and machinery before maintenance or servicing, using clearly visible markers to signify that the equipment is not to be operated, safeguards workers from the unexpected startup or release of stored energy. This encompasses electrical, mechanical, hydraulic, pneumatic, chemical, and thermal energy sources. For example, locking a circuit breaker in the “off” position and placing a tag on it describing the work being performed and who is responsible prevents accidental re-energization while someone is working on the circuit.
This critical safety procedure prevents serious injuries and fatalities associated with hazardous energy. Its implementation significantly reduces workplace accidents and contributes to a safer working environment. Historically, numerous incidents involving unexpected equipment activation led to the development and standardization of these procedures, ultimately saving countless lives and limbs.