They are protected by halo grounds with ground wire that are cadmium welded to ground rods located around the tower (creating a circle). In addition the antenna lines are grounded every 10 feet using a ground kit that is connected to the copper shield in the cable. The lines that connect to the equipment all have polyphasers (lightning arrstors) on the return lines that do not allow power (lightning) to pass through. This system will help alleviate trouble but in the end the lightning damage would occur. PS: Polyphasers will not work on the satellie lines. I tried and it would not pass the voltage through the line.