What is touch potential and how does proper grounding affect it?

• A. Touch potential is a term with no real meaning in safety practices.
• B. Touch potential is the voltage difference a person may feel when touching a live part in fault conditions; proper grounding reduces stray voltages, stabilizes potential, and lowers touch potential.
• C. Touch potential is the voltage between two conductors in normal operation.
• D. Touch potential is solely determined by PPE and not by grounding.

Answer: (B)

Touch potential is the voltage a person may feel between a body and earth (or between touched surfaces) when a fault causes a live part to be exposed. Proper grounding provides a low-impedance path for fault current to the earth and bonds all exposed conductive parts to that same reference. When this happens, those parts stay near earth potential, so the voltage difference a person could experience is kept small. In other words, grounding stabilizes the system’s potential and reduces stray voltages that could occur during fault conditions, lowering the risk of shock. PPE protects you from voltage you might encounter, but it doesn’t change the actual voltage on surfaces; grounding does.