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LIGHTNING: 
A Potentially Deadly Strike With Each Flash


National Lightning Safety Awareness Week 
June 22-28, 2014


A strike spotted on Lake Coeur d'Alene.

For Release: June 22, 2014
Contact: Andrew Brown@noaa.gov , National Weather Service Spokane, WA (509) 244-0110 ext 223

Every year lightning kills approximately 70 people and injures another 300. In the United States, there are an estimated 25 million cloud-to-ground lightning flashes each year, and a recent storm system over the Ark-La-Tex region produced 17,000 strikes within one hour!

There are several very easy things to remember when it comes to lightning safety:

Lightning: What You Need to Know

  • NO PLACE outside is safe when thunderstorms are in the area!
  • If you hear thunder, lightning is close enough to strike you.
  • When you hear thunder, immediately move to safe shelter: a substantial building with electricity or plumbing or an enclosed, metal-topped vehicle with windows up.
  • Stay in safe shelter at least 30 minutes after you hear the last sound of thunder.

 

Outdoor Safety: Most lightning deaths and injuries in the United States occur during the summer months when the combination of lightning and outdoor summertime activities reaches a peak. During the summer, people take advantage of the warm weather to enjoy a multitude of outdoor recreational activities. Unfortunately, those outdoor recreational activities can put them at greater risk of being struck by lightning. People involved in activities such as farming, boating, swimming, fishing, bicycling, golfing, jogging, walking, hiking, camping, or working out of doors all need to take the appropriate actions in a timely manner when thunderstorms approach. Where organized sports activities take place, coaches, umpires, referees, or camp counselors must protect the safety of the participants by stopping the activities sooner, so that the participants and spectators can get to a safe place before the lightning threat becomes significant. To reduce the threat of death or injury, those in charge of organized outdoor activities should develop and follow a plan to keep participants and spectators safe from lightning.

Indoor Safety: There are three main ways lightning enters homes and buildings:

1. a direct strike, 
2. through wires or pipes that extend outside the structure, and 
3. through the ground. 
Regardless of the method of entrance, once in a structure, the lightning can travel through the electrical, phone, plumbing, and radio/television reception systems. Lightning can also travel through any metal wires or bars in concrete walls or flooring.

Phone use is the leading cause of indoor lightning injuries in the United States. Lightning can travel long distances in both phone and electrical wires, particularly in rural areas. Stay away from windows and doors as these can provide the path for a direct strike to enter a home. Do not lie on the concrete floor of a garage as it likely contains a wire mesh. In general, basements are a safe place to go during thunderstorms. However, there are some things to keep in mind. Avoid contact with concrete walls which may contain metal reinforcing bars. Avoid washers and dryers since they not only have contacts with the plumbing and electrical systems, but also contain an electrical path to the outside through the dryer vent.

Lightning also causes significant damage to personal property each year. In addition to direct strikes, lightning generates electrical surges that can damage electronic equipment some distance from the actual strike. Typical surge protectors will NOT protect equipment from a lightning strike. To the extent possible, unplug any appliances or electronic equipment from all conductors well before a thunderstorm threatens. This includes not only the electrical system, but also the reception system. If you plan to be away from your home when thunderstorms are possible, be sure to unplug unneeded equipment before you leave.

For more information on lightning safety, the National Weather Service has partnered with many different groups and agencies to create the National Lightning Safety web site. It is at: www.lightningsafety.noaa.gov.