From "Lightning & Surge Protection" on SECO Energy faq page;
Lightning & Surge Protection:
Is there any other lightning protection used in Florida for houses other than an indoor surge protection system, like lightning rods or ground rods?
Lightning rods, more correctly called air terminals (or Franklin rods after the inventor), are used in Florida. There are several companies located in Lake and Marion counties in the telephone directory listed under "Lightning Protection Equipment." Most electrical contractors should also be able to make a recommendation. SECO does not recommend any specific provider or vendor. Correct installation is the key and it is expensive. Lightning rods are by design a device that attracts lightning. When installed correctly to code, they divert the stroke to ground. The problem is that many people do not want to spend the money necessary to make secure connections from the rod to a sufficient size down lead cable to a proper ground with proper connection, or to pay to have them routinely inspected. Therefore what happens is the rod attracts lightning, and it sees the internal house systems as a better "route to ground" and ends up dissipating throughout the home causing major damage.
Securing a good, low resistance ground rod connection in Florida is hard to do and requires professional assistance to achieve using precision ground measuring equipment. Typically at SECO we will often drive 70 foot, or multiple rods, in a grid configuration and in a few places 90 feet of rod with connections cad-welded to the rod in order to achieve a ground below 30 ohms. Therefore the single 6-8 foot rod purchased at a hardware/electronic type store is virtually useless with undersized and poorly clamped wire tied to it and it can cause more problems than without. Most communications towers (cellular, broadcast stations and virtually all government complexes) at major locations utilize a device called a dissipation array which deters lightning from wanting to strike a structure in the first place. This technology also requires a good ground grid around the complex and proper low resistance grounding. Normally this would not be seen utilized on a residential home. If you look at a broadcast tower and see a circular device on top with many little wire brush like spikes coming out of it, that is a dissipation array. For more information and practical solutions, contact Customer Service to schedule a visit to discuss things that you, as a homeowner, can do to enhance your in-home protection system, such as our surge protection program, common point grounding and insuring that outlets are properly wired with a ground attached to the proper terminal in electrical sockets.
Another thing to keep in mind when trying to compare Florida weather to that of the northern states is that we live in the highest lightning strike region of the nation, the actual center of which is located near Lakeland, Florida. Only one place in the world, a section of Africa, is higher. Therefore, you will find the lightning strike activity in our area more vicious and more frequent than experienced anywhere else in the U.S. This means that what might work in other areas may not be sufficient or work here at all.
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