Q. HOW FREQUENTLY DOES LIGHTNING STRIKE IN THE UNITED STATES?
A. An average of 52 times per square mile per year, a total of about
90,000,000 bolts.
Q. WHY DOES LIGHTNING SO FREQUENTLY STRIKE BUILDINGS AND OTHER OBJECTS?
A. It seeks easy paths. Most building materials are poor conductors of
electricity but still offer much less resistance than air. Buildings are
used as ladders and congregating points for ground charges.
Q. HOW ARE BUILDINGS IGNITED OR DAMAGED BY LIGHTNING?
A. Resistance to passage of the lightning bolt causes friction and
tremendous heat, resulting in fire or explosion, or both.
Q. ARE LOW, SMALL BUILDINGS SUBJECT TO LIGHTNING STRIKES?
A. Yes. Any ground structure that serves as a ladder and a site for
positive ground charges to accumulate is a target.
Q. CAN BUILDINGS BE MADE ABSOLUTELY SAFE FROM DAMAGE FROM LIGHTNING?
A. Yes. A Thompson Lightning Protection system will conduct lightning
to the ground without allowing the charge to enter and damage the building.
Q. DO HIGH TREES ADJACENT TO AN UNPROTECTED BUILDING PROTECT IT?
A. No. In fact, if lightning hits such a tree, it is quite likely the
bolt will then leap to the house in search of better ground - or the
damaged tree may in turn damage the house. Protect such trees.
Q. IS A BUILDING WITH METAL ROOF AND SIDES SAFE?
A. Only if protected with air terminals, conductors and ground rods because the
metal sheeting provides no protection.
Q. DO LIGHTNING RODS ATTRACT LIGHTNING?
A. No part of a lightning protection system "attracts" lightning. A
lightning protection system offers a safe path to ground.
Q. ARE STRUCTURES WITH FIREPROOF ROOFS SAFE FROM DAMAGE OR DESTRUCTION BY LIGHTNING?
A. No. Although a roof of this type will not be ignited as easily, its
resistance will cause it to be badly damaged.