A lightning rod is a metal rod that sticks up from a roof that will carry the current from a lightning strike safely to ground. It is typically copper or aluminum today, although Benjamin Franklin experimented with other metals in his original lightning protection systems. Some can be hollow to eliminate the weight of the lightning rod, and that meets code. At BASE Lighting Protection, we use solid air terminals because a solid air terminal, although not always necessary, can handle a greater charge if the situation demands – whether or not that situation should arise. Lightning rods can also be rounded at the top like the original ones in England, or spike tipped like the ones Benjamin Franklin pioneered here in the U.S. Each has its own advantages.
Today, the lightning protection industry has started to shy away from the term ‘lightning rod’ in favor of our new, more inclusive term of ‘air terminal.’ As you see in our picture, you don’t need a rod to carry the current. You see Mickey Mouse up there? He is an air terminal. Our friends in Orlando work closely with Disney to disguise their lighting protection systems. Disney has some of the most creative lightning protection systems in the world. In order to do that, they had to veer away from the typical lightning rods we saw in years past.
Nowhere in our lightning protection codes does it require that these metal objects that intercept the current before it touches a building has to be a rod. In fact, we in the community like to “nerd out” when we see an air terminal that isn’t a rod. Code specifies that we can substitute rods for metal objects at least 3/16″ thick that can carry the current safely to the ground. Code also specifies that the object has to be 10″ above the structure it needs to protect. Mickey, here, is tied into the system in a less conspicuous way than the average lighting protection system. Mickey also sits at the peak of the building, effectively protecting the building. He was custom-made to be the correct thickness in order to pass the required codes and is just as effective as any old lightning rod.
There are tons of other ways that we can disguise lightning protection. We wrote another article that talks about all the different ways that we can bypass using lightning rods. You can put a deck on the top of your house or high rise building and use metal railings to connect into the system.
For these reasons, the industry prefers the term ‘air terminal.’ We can more effectively communicate when we understand that there are many creative, innovative ways to meet code and please a client.