What steps you recommend to prevent flash over on High Voltage and Extra High Voltage transmission lines in highly salt charged coastal areas?

• Identify all possible sources of supply.  Electric equipment such as breakers, capacitors, and bus bars can be fed from more than one supply.
• All switching equipment should be opened and visually verified if possible
• Lock out/Tag out devices should be applied.
• Voltage testers with hot rods should be used to check that the devices are dead.  All devices should be considered live if not earthed.
• Grounding rods should be used to discharge energy stored device (High voltage devices will retain voltage even after the supply has been switched off due to capacitance).  The equipment on which work is conducted should be kept grounded throughout the duration of the maintenance activity(as a precaution against induced voltage or accidentally coming in contact with live parts)

Recommend to use Porcelain Insulator.