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)

A proper Flash over Hazard Analysis should be carried out at all device locations.  A Flash over Hazard Analysis calculates the maximum current, the maximum energy which will be dissipated in the event of a Flash over and the Personnel Protection Equipment which is to be used.

glass insulation with an increased escape line

Recommend to use Porcelain Insulator.