What are the steps of the Hot-Cold-Hot procedure?

• A. Check Known Power Source, Check Equipment That Has Been Deenergized, Check Known Power Source Again
• B. Check Equipment That Has Been Deenergized, Check Known Power Source Again, Check Equipment That Has Been Deenergized
• C. Check Known Power Source Again, Check Equipment That Has Been Deenergized, Check Known Power Source
• D. Check Known Power Source, Check Known Power Source Again, Check Equipment That Has Been Deenergized

Answer: (A)

The idea behind Hot-Cold-Hot is to confirm a circuit is safely deenergized by verifying the energy state before, during, and after isolation. Start by checking the known power source so you know exactly what you need to shut off and what path energy could take. Then deenergize the equipment and test the circuit to confirm there is no voltage present where you will be working—this “cold” step verifies the equipment is truly deenergized. Finally, re-check the power source again to catch any reenergization or backfeed that could have occurred while you were working. This sequence minimizes the chance of shock or arc flash by ensuring energy is removed and remains removed during maintenance.