Question

What does the term lockout/tagout refer to?

Answer 1

Lockout/Tagout exists to prevent unexpected start up of the equipment or energy to prevent injury to the employee while servicing. 
Lockout-tagout (LOTO) or lock and tag is a safety procedure which is used in industry and research settings to ensure that dangerous machines are properly shut off and not started up again prior to the completion of maintenance or servicing work. A disconnect switch, circuit breaker, manually operated valve, blind flange and any other device used to ensure that power or energy can not flow to a piece of machinery or equipment 

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Answer 2

The term lockout tagout (LOTO) refers to a safety procedure that ensures that dangerous machines and energy sources are properly shut off and not unexpectedly started up before the completion of maintenance or servicing work. These energy sources could include electrical, mechanical, hydraulic, pneumatic, chemical, radiation, and thermal hazards. The point of a LOTO procedure is to identify a hazard that may injure or even kill employees if such an incident occurs due to the startup or release of stored energy during the maintenance of machines and equipment.