What is lockout/tagout, and why is it important?

• A. A method to label tools before use.
• B. A process to calibrate instruments.
• C. A technique to speed up maintenance.
• D. A safety procedure to isolate energy sources and tag them to prevent accidental energization during maintenance.

Answer: (D)

Lockout/tagout is a safety process used to control hazardous energy when workers service or repair equipment. It involves identifying all energy sources, isolating the equipment from those sources, and applying a lock and a tag to energy‑isolation devices so the equipment cannot be energized or released unexpectedly during maintenance. The lock physically prevents re-energizing, while the tag warns others not to operate the equipment. This dramatically reduces the risk of electric shocks, burns, or injuries from unexpected startup or stored energy. Tools labeling, instrument calibration, or trying to speed up maintenance don’t address the risk of unexpected energization, which is why lockout/tagout is the correct concept.