What is electrical isolation?

• A. Isolating Electrical Equipment
• B. Isolating Mechanical Equipment
• C. Shutting Down All Systems
• D. Tagging Circuits Only

Answer: (A)

Electrical isolation means separating a circuit or piece of equipment from all sources of electrical energy and any stored energy so that maintenance can be performed safely. It involves de-energizing the equipment, physically isolating it (such as opening a disconnect or removing a fuse), applying a lockout/tagout if required, and confirming with a test that no voltage remains.

This is accomplished by isolating electrical equipment because that directly prevents energization and potential shock or energy release during work. Tagging alone does not stop current, and shutting down all systems is unnecessarily broad and not the precise action needed for a single piece of equipment. Isolating mechanical equipment misses the electrical energy aspect entirely.