Heath Howe
English 101
November 5, 2011
Lightning Protection Systems
Did you know that last year, in the United States, property loss due to lightning strikes exceeded one billion dollars? The average homeowner’s insurance paid $4,296 per lightning claim and an average of two hundred fifty thousand insurance claims were filed strictly due to lightning. In January 2003, the American Meteorologist Society issued a bulletin endorsing the lightning protection requirements embodied in the National Fire Protection Association Standard 780. Stating, “It is now well established that properly installed and maintained lightning rod based protection systems significantly decrease lightning damage.” The only true way to protect a structure from a direct lightning strike is with a lightning protection system. A lightning protection system, with proper installation can save lives, protect structures, and provide peace of mind.
To understand lightning protection, you first need to understand lightning. Lightning, by definition, is the discharge of static electricity from cloud-to-ground. Lightning is the energy created by friction from the rise and fall of hot and cold air masses in the clouds. This energy, which is only visible as lightning, retains a negative charge. To equalize, this negative charge must contact a positive charge, which is held by ground. The positive charge and the negative charge seek the best route to meet and dissipate; meaning that lightning is only looking for a way to obtain ground. Lightning decides on a target no more than 500 feet prior to striking and does not discriminate on what it strikes.
Lightning protection systems provide an efficient path for lightning to reach the ground safely, without destroying structures. The system does not attract lightning, nor deter, but rather acts as a canopy of protection. Lightning protection systems are interconnected to form a “cage” around the perimeter
References: * American Meteorology Society Statement on Lightning Protection, Bulletin of the American Meteorology Society, January, 2003, Pp 117-121 * LPI 175, Third Edition, Lightning Protection Institute, 1987. * NFPA 780, 2008 Edition, “Standard for the Installation of Lightning Protection Systems”, National Fire Protection Association * UL 96A, Eleventh Edition, Underwriters Laboratories, 2001.