Service and maintenance of electrical machines require a what system?

• A. Lock out tag out
• B. Permit to Work
• C. Job Safety Analysis
• D. Personal Protective Equipment

Answer: (A)

Controlling hazardous energy during service and maintenance is essential. A lockout-tagout system provides a formal method to isolate electrical equipment from its energy sources and prevent unexpected energization while work is performed. Locks physically secure energy‑isolating devices, and tags warn that the equipment must not be operated. After the work is complete and the area is verified safe, the locks are removed only by the person who applied them. This approach directly prevents accidental startup and stored-energy release, which are the main risks during maintenance. Permit to Work helps authorize tasks, but does not itself isolate energy. A Job Safety Analysis identifies hazards, but does not guarantee zero energy. PPE protects the worker, but does not control the energy source. So, the system best suited for service and maintenance of electrical machines is lockout-tagout.