What is the difference between lockout and tagout?

• A. Lockout uses a tag-based warning system.
• B. Tagout uses a physical locking device to prevent energy release.
• C. Lockout uses a tag only, with no physical device.
• D. Lockout uses a physical device to prevent energy release; tagout uses a tag to warn that the equipment is not to be energized, but provides less physical protection.

Answer: (D)

The main idea here is how hazards are controlled during maintenance by isolating energy sources. Lockout involves applying a physical locking device to the energy-isolating point (like a switch or valve) so the equipment cannot be energized until the lock is removed. Tagout, on the other hand, uses a warning tag to indicate the equipment should not be energized, but it doesn’t provide the same level of physical protection because the device could be bypassed or removed more easily. So lockout offers a physical barrier to energy release, while tagout relies on warnings and procedures with less inherent protection. The other statements mix up which method uses a physical lock versus a tag, so they don’t fit the actual distinction.