What is Lightning Protection?
The highly conductive copper and aluminum materials used in a lightning protection system provide a low resistance path to safely ground lightning’s dangerous electricity. When the lightning protection network is in place, the lightning strike is intercepted and directed to ground without impact to the structure, occupants or contents.
A Lightning Protection System that meets national safety standards includes the following elements:
- Strike termination network (air terminals or lightning rods)
- Down-conductor network
- Grounding electrode network
- Equipotential bonding network
- Surge protection devices (for all incoming power, data and communication lines)
Failure to make proper provisions for special grounding techniques, or any of the above five elements can result in inadequate protection.
How Effective is a Lightning Protection system?
In January 2003 the American Meteorologist Society issued a Bulletin endorsing the lightning protection requirements, stating:
“It is now well established that properly installed and maintained lightning rod-based protection systems significantly decrease lightning damage.”
In 2001 a joint paper was issued by lightning experts at the U.S. Army, Navy, Air Force, Nat’l Severe Storms Laboratory, Defense Explosives Safety Board, Dept of Energy, NASA and FAA. This paper underscores the critical role that lightning protection systems play in protecting national infrastructure.
Making a Difference
Environment Canada keeps an updated Canadian Lightning Danger Map (CLDM) on their website that highlights areas that are at the greatest risk of being struck by lightning in the next 10 minutes. (It is based on strikes that have been recorded in the last 20 minutes.) The red areas on the map indicate that lightning is striking there and you are in immediate danger if outdoors.
Lightning-related deaths and injuries have dropped by 80% over the last 75 years. This is partly due to increased lightning safety awareness efforts by partnering organizations like the American NOAA/National Weather service, the Insurance Information Institute, the Lightning Safety Alliance, the Lightning Protection Institute and Environment Canada.