What action may be required to mitigate icing-related flashover risk?

• A. De-icing may be required.
• B. Remove insulation completely.
• C. Increase voltage to improve field strength.
• D. Apply hydrophobic coatings only.

Answer: (D)

When ice and moisture affect insulator surfaces, a continuous wet film can form and provide a conductive path along the creepage distance, increasing the chance of flashover under voltage stress. A hydrophobic coating changes how water interacts with the surface: it makes water bead up into discrete droplets rather than spreading into a continuous film. This reduces the wetted area and the surface conductivity, so leakage currents stay lower and the voltage needed to trigger flashover rises. Because this coating provides a passive, durable way to limit the formation of conductive water films during icing, it can be a practical mitigation that remains effective through freezing and wetting cycles. De-icing is another approach, but the coating specifically helps reduce the risk by controlling surface wetting; the other options would not address the surface leakage behavior in icing conditions.