What are the three basic measures to avoid electric shock?

• A. Insulation, isolation, bonding
• B. Insulation, shielding, grounding
• C. Grounding, insulation, shielding
• D. Insulation, isolation, grounding

Answer: (D)

Preventing electric shock relies on three practical measures: insulation, isolation, and grounding. Insulation uses non-conductive barriers to stop current from reaching a person or touching exposed conductors. Isolation keeps live parts physically separated from people, so access to energized components is prevented or controlled. Grounding provides a low-resistance path for any fault current, which helps keep exposed surfaces at a safe potential and triggers protective devices to disconnect power quickly. Shielding is not a primary method for preventing shock, and bonding, while related to maintaining equal potential, is not the standard trio on its own.