Which statement describes a core requirement of lockout/tagout procedures during maintenance?

• A. Verify zero energy state before maintenance.
• B. Just notify maintenance without isolation.
• C. Only used for electrical systems in plants.
• D. Applicable only during emergencies.

Answer: (B)

Preventing unexpected energization is the key idea behind lockout/tagout. Before any maintenance, the equipment must be confirmed to be in a zero-energy state, meaning all energy sources are isolated, released, or restrained, and workers have a lock or tag on the isolating devices so no one can re-energize the machine while work is being done. Merely notifying someone about maintenance does not provide this level of protection or control. Lockout/tagout covers all types of energy—not just electrical systems in plants—and is a routine safety practice during maintenance, not something reserved for emergencies.