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Lightning Facts and Safety Tips In the United States, an average of 73 people are killed each year by lightning. That's more than the annual number of people killed by tornadoes or hurricanes. Many more are struck but survive. However, they often report a variety of long-term, debilitating symptoms, including memory loss, attention deficits, sleep disorders, numbness, dizziness, stiffness in joints, irritability, fatigue, weakness, muscle spasms, depression, and an inability to sit for long. Lightning is a serious danger. Through this site we hope you'll learn more about lightning risks and how to protect yourself, your loved ones and your belongings. We’d like to thank the following contributors to this site. NOAA, Federal Emergency Management Agency, American Red Cross, Li9ghtning Injury Research, IBHS – Institute for Better home Safety, Global Atmospheric Inc. The Weather Channel, National Lightning Safety Institute.
Lightning & Lightning Safety - An Introduction
Lightning - The Underrated Killer
In the United States, there are an estimated 25 million cloud-to-ground lightning flashes each year. While lightning can be fascinating to watch, it is also extremely dangerous. During the past 30 years, lightning killed an average of 73 people per year in the United States based on documented cases. This is more than the average of 68 deaths per year caused by tornadoes and the average of 16 deaths per year caused by hurricanes. However, because lightning usually claims only one or two victims at a time, and because lightning does not cause the mass destruction left in the wake of tornadoes or hurricanes, lightning generally receives much less attention than the more destructive weather-related killers. While documented lightning injuries in the United States average about 300 per year, undocumented injuries caused by lightning are likely much higher.
Lightning Safety Awareness - An Educational Problem
While many people think that they are aware of the dangers of lightning, the vast majority are not. The lack of understanding with regard to the dangers of lightning continues to be a significant problem in the United States. Many people don't act to protect their lives, their property, and the lives of others in a timely manner simply because they don't understand all the dangers associated with thunderstorms and lightning. The first step in solving this problem is to educate people so that they become aware of the behavior that puts them at risk of being struck by lightning, and to let them know what they can do to reduce that risk. For those adults who make decisions that affect the safety of children, understanding the dangers of lightning is extremely important. Unfortunately, many people's knowledge of lightning safety is tragically in error.
Beware of a Developing Thunderstorm
Thunderstorms are most likely to develop on warm summer days and go through various stages of growth, development and dissipation. On a sunny day, as the sun heats the air, pockets of warmer air start to rise in the atmosphere. When this air reaches a certain level in the atmosphere, cumulus clouds start to form. Continued heating can cause these clouds to grow vertically upward in the atmosphere into "towering cumulus" clouds. These towering cumulus may be one of the first indications of a developing thunderstorm.
The Lightning Discharge - Don't Be A Part Of It
During a thunderstorm, each flash of cloud-to-ground lightning is a potential killer. The determining factor on whether a particular flash could be deadly depends on whether a person is in the path of the lightning discharge. In addition to the visible flash that travels through the air, the current associated with the lightning discharge travels along the ground. Although some victims are struck directly by the main lightning stroke, many victims are struck as the current moves in and along the ground. While virtually all people take some protective actions during the most dangerous part of thunderstorms, many leave themselves vulnerable to being struck by lightning as thunderstorms approach, depart, or are nearby.
An Approaching Thunderstorm - When Should I Seek Safe Shelter?
Lightning can strike as much as 10 miles away from the rain area in a thunderstorm; that's about the distance that you are able to hear the thunder from the storm. In some instances when a storm is ten miles away, it may even be difficult to tell that a storm is nearby. However, IF YOU CAN HEAR THE THUNDER FROM A STORM, CHANCES ARE THAT YOU ARE WITHIN STRIKING DISTANCE OF THAT STORM. Also, remember that each thunderstorm has a first stroke of lightning, which is just as deadly as any other stroke. If the sky looks threatening, take shelter before hearing thunder. Outdoor Activities - Minimizing The Risk Of Being Struck
The greatest number of lightning deaths and injuries in the United States occurs 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. Those involved in activities such as 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 are taking 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 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 to a plan to keep participants and spectators safe from lightning.
Indoor Activities - Things To Avoid
Inside homes, people must also avoid activities which put their lives at risk from a possible lightning strike. As with the outdoor activities, these activities should be avoided before, during, and after storms. In particular, people should stay away, from windows and doors and avoid contact with anything that conducts electricity. People may also want to take certain actions well before the storm to protect property within their homes, such as electronic equipment.
If Someone is Struck, What Do I Do?
In the unfortunate event that a person is struck by lightning, medical care may be needed immediately to save the person's life. Cardiac arrest and irregularities, burns, and nerve damage are common in cases where people are struck by lightning. However, with proper treatment, including CPR if necessary, most victims survive a lightning strike, although the long-term effects on their lives and the lives of family members can be devastating.
Have A Lightning-Safe Summer!
In summary, lightning is a dangerous threat to people in this country, particularly to those outside in the summer. However, with the appropriate precautions, the number of lightning casualties in this country could be greatly reduced. In general, when thunderstorms threaten, get to a safe place sooner, stay there longer, stay away from windows and doors, avoid contact with anything that conducts electricity, and enjoy a safe summer! Why do some clouds produce lightning and others don't? Lightning Is A Random, Chaotic And Dangerous Fact Of Nature
At any given moment, there are 1,800 thunderstorms in progress somewhere on the earth. This amounts to 16 million storms each year! For as long as humans have watched the skies, lightning has fascinated and frightened them. Scientists that study lightning have a better understanding today of the process that produces lightning, but there is still more to learn about the role of solar flares that impact the upper atmosphere, the earth's electromagnetic field, and ice in storms. We know the cloud conditions necessary to produce lightning, but cannot forecast the location or time of the next stroke of lightning from a storm. There are lightning detection systems in the United States and they monitor an average of 25 million strokes of lightning from the cloud to ground every year! Lightning has been seen in volcanic eruptions, extremely intense forest fires, surface nuclear detonations, heavy snowstorms, and in large hurricanes. However it is most often seen in individual thunderstorms. A thunderstorm forms in air that has three components: moisture, instability and something such as a cold front to cause the air to rise. Continued rising motions within the storm may build the cloud to a height of 35,000 to 60,000 feet (6 to 10 miles) above sea level. Temperatures higher in the atmosphere are much colder, and ice forms in the higher parts of the cloud.
Ice In The Cloud Is Critical To The Lightning Process
The formation of ice in a cloud appears to be a very important element in the development of lightning and those storms that fail to produce quantities of ice may also fail to produce lightning. In a storm, the ice particles vary in size from small ice crystals to larger hailstones, but in the rising and sinking motions within the storm there are a lot of collisions between the particles. This causes a separation of electrical charges. Positively charged ice crystals rise to the top of the thunderstorm, and negatively charged ice particles and hailstones drop to the middle and lower parts of the storm. Enormous charge differences (electrical differential) develops.
How Lightning Develops Between The Cloud And The Ground
A moving thunderstorm gathers another pool of positively charged particles along the ground that travel with the storm. As the differences in charges continue to increase, positively charged particles rise up taller objects such as trees, houses, and telephone poles. Have you ever been under a storm and had your hair stand up? Yes, the particles also can move up you! This is one of nature's warning signs that says you are in the wrong place, and you may be a lightning target!
The negatively charged area in the storm will send out a charge toward the ground called a stepped leader. It is invisible to the human eye, and moves in steps in less than a second toward the ground. When it gets close to the ground, it is attracted by all these positively charged objects, and a channel develops. You see the electrical transfer in this channel as lightning. There may be several return strokes of electricity within the established channel that you will see as flickering lightning.
Thunder
The lightning channel heats rapidly to 30,000 degrees. The rapid expansion of heated air causes the thunder. Since light travels faster than sound in the atmosphere, the sound will be heard after the lightning. If you are ever in a storm when you see the lightning and hear the thunder at the same time, that lightning is in your neighborhood!
Negative Lightning And Positive Lightning
Not all lightning forms in the negatively charged area low in the thunderstorm cloud. Some lightning originates in the cirrus anvil at the top of the thunderstorm. This area carries a large positive charge, and lightning from this area is called positive lightning. This type is particularly dangerous for several reasons. It frequently strikes away from the rain core, either ahead or behind the thunderstorm. It can strike as far as 5 or 10 miles from the storm, in areas that most people do not consider to be a lightning risk area. The other problem with positive lightning is it typically has a longer duration, so fires are more easily ignited. Positive lightning usually carries a high peak electrical current, which increases the lightning risk to an individual.
Lightning Safety OutdoorsThe Single Most Dangerous Place
Being out-of-doors is the most dangerous place to be during a lightning storm. It puts you and your loved ones at increased and unnecessary risk. When lightning is seen or thunder is heard, or when dark clouds are observed, quickly move indoors or into a hard-topped vehicle and remain there until well after the lightning storm ends. Listen to forecasts and warnings from your local National Weather Service Office through NOAA Weather Radio and other sources. If lightning storms are forecast, have in mind an alternate plan for the day's activities or know where you can take cover quickly. Lightning Doesn't Take A Vacation
The lightning "season" in the United States corresponds closely with the traditional summer vacation. Holiday periods during the summer such as near the Fourth of July are historically among the most deadly. Throughout the summer, a lot more people are exposed to the deadly effects of lightning in such locations as the beach, the golf course, the mountains, or on a ball field. During the summer lightning season, outdoor jobs such as those in construction and agriculture, and outdoor chores such as lawn mowing or house painting are at their peak, putting those involved in danger. This is highlighted by the fact that there are three times as many males struck by lightning.
Stay Away From Trees and Water
Although anywhere outdoors involves risk during a lightning storm, certain locations are more vulnerable then others. These include: near the water, such as when involved in boating, fishing or just lying on the beach; near trees, such as on the golf course or near picnic grounds; on high places such as house roofs during construction or working on antennae; in other open areas, such as a farmer’s field or hiking trail; near vehicles or planes such as police, airport baggage handlers and heavy equipment operators.
When People Congregate
A particularly dangerous situation is when people congregate such as at a sporting event or concert. The potential for multiple casualties with a closely gathered group of people is great. A single lightning strike can kill several people who are either in physical contact with one another or are in close enough proximity that the strike can spread out over the ground. This includes spectators sitting on the same bleacher seat or football players in a huddle. School children are particularly vulnerable when at recess, at phys. ed., at band, football and baseball practice, and walking in groups to and from school.
Safety Rules
1.Go quickly inside a completely enclosed building, not a carport, open garage, covered patio, or an open window 2.If no enclosed building is convenient, get inside a hard-topped all-metal vehicle 3.Do not take shelter under a tree. 4.If there is no shelter, avoid being the tallest object in the area. If only isolated trees are nearby, crouch on the balls of your feet in the open, keeping twice as far away from a tree as it is tall. 5.Avoid leaning against vehicles. Get off bicycles and motorcycles 6.Get out of the water...off the beach and out of small boats or canoes. If caught in a boat, crouch down in the center of the boat away from metal hardware. Avoid standing in puddles of water, even if wearing rubber boots. 7.Avoid open spaces, wire fences, metal clothes lines, exposed sheds and electrically conductive elevated objects. 8.Do not use metal objects like golf clubs, fishing rods, tennis rackets or tools 9.Do not work on fences, telephone or power lines, pipelines, or steel fabrications 10.Stop tractor work and heavy construction equipment, especially when pulling metal equipment, and dismount. Do not seek shelter under the equipment. 11.Avoid congregating in groups. Do not hold hands with others and space yourself several yards from one another.
Becoming familiar with outdoor lightning safety rules can save your life or that of a loved one.
Safe Shelters & Indoor Safety
What is a Safe Shelter?
A house or other substantial building offers the best protection from lightning. In assessing the safety provided by a particular structure, it is more important to consider what happens if the structure gets struck by lightning, rather than whether the structure will be hit by lightning. For a shelter to provide protection from lightning, it must contain a mechanism for conducting the electrical current from the point of contact to the ground. These mechanisms may be on the outside of the structure, may be contained within the walls of the structure, or may be a combination of the two. On the outside, lightning can travel along the outer shell of the building or may follow metal gutters and downspouts to the ground. Inside a structure, lightning can follow conductors such as the electrical wiring, plumbing, and telephone lines to the ground.
Avoid Unsafe Shelters!
Unless specifically designed to be lightning safe, small structures do little, if anything, to protect occupants from lightning. Many small open shelters on athletic fields, golf courses, parks, roadside picnic areas, schoolyards and elsewhere are designed to protect people from rain and sun, but not lightning. A shelter that does not contain plumbing or wiring throughout, or some other mechanism for grounding from the roof to ground is not safe. Small wooden, vinyl, or metal sheds offer little or no protection from lightning and should be avoided during thunderstorms.
How Lightning Enters a House or Building
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.
Stay Safe While Inside
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.
Remember Your Pets
You may want to consider the safety of your family pets during thunderstorms. Doghouses are not lightning-safe. Dogs that are chained to trees or chained to wire runners can easily fall victim to a lightning strike.
Protect Your Personal Property
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. 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.
Summary of Lightning Safety Tips for Inside the Home
1.Avoid contact with corded phones 2.Avoid contact with electrical equipment or cords. If you plan to unplug any electronic equipment, do so well before the storm arrives. 3.Avoid contact with plumbing. Do not wash your hands, do not take a shower, do not wash dishes, and do not do laundry. 4.Stay away from windows and doors, and stay off porches. 5.Do not lie on concrete floors and do not lean against concrete walls.
Medical Aspects of Lightning
How Big A Problem Is This? Statistics
Lightning has been the second largest storm killer in the US for the last forty years, exceeded only by floods. The only cause of death from lightning is from cardiac arrest at the time of the injury, although some may appear to have a delayed death a few days later if they are resuscitated but have suffered irreversible brain damage. According to ‘Storm Data', a National Weather Service publication, an average of 73 lightning fatalities occur each year. Due to underreporting, the figures are more realistically about 100 deaths per year. Only about 10% of people who are struck are killed, leaving 90% with various degrees of disability.
Affects on the Family
While any death is a blow to a family, eventually the family readjusts and goes on. However, for those who have a relative who suffers significant disability from lightning, life changes forever and the dreams of that family and the survivor may be markedly altered. The family income may be tremendously decreased if the survivor was one of the breadwinners or the spouse or another family member may have to quit work to care for the survivor if the disability is great enough.
Who Gets Injured
While about one third of all injuries occur during work, workers compensation companies are often reluctant to acknowledge the injury or pay their medical expenses. About another third of injuries occur during recreational or sports activities. The last third occurs in diverse situation, including injuries to those inside buildings.
Injury Prevention
Many injuries in each of these groups can be prevented with: Proper education about lightning risks and safety measures; Well conceived lightning protection systems that protect people and equipment.
Safe places for people
Lightning safety plans for coaches, parents, and referees at sporting events and other outdoor group activities should be prepared. While lightning safety and injury prevention may be judged to be an individual responsibility and decision for an adult, adults should be aware that they are ALWAYS responsible for the children in their care, particularly if it is an outdoor activity such as soccer, t-ball, camping, etc. Unlike high voltage electrical injuries, where massive internal tissue damage may occur, lightning seldom causes substantial burns. In fact, most of the burns are caused by other objects (rainwater, sweat, metal coins and necklaces, etc) being heated up and causing the burn rather than caused by the lightning itself.
How Does Lightning Injury Affect People?
Lightning tends to be a nervous system injury and may affect any or all parts of the nervous system: the brain, the autonomic nervous system, and the peripheral nervous system. When the brain is affected, the person often has difficulty with short-term memory, coding new information and accessing old information, multitasking, distractibility, irritability and personality change. A great quote sums it up perfectly:
"Patients have difficulty in all areas that require them to analyze more items of information than they can handle simultaneously. They present (appear) as slow because it takes longer for smaller than normal chunks of information to be processed. They present as distractible because they do not have the spare capacity to monitor irrelevant stimuli at the same time as they are attending to the relevant stimulus. They present as forgetful because while they are concentrating on point A, they do not have the processing space to think about point B simultaneously. They present as inattentive because when the amount of information that they are given exceeds their capacities, they cannot take it all in."
Early on, survivors may complain of intense headaches, ringing in the ears, dizziness, nausea, vomiting and other post-concussion types of symptoms. Survivors may also experience difficulty sleeping, sometimes sleeping excessively acutely after the injury but changing during the next few weeks to inability to sleep more than two or three hours at a time. A few may develop persistent seizure-like activity several weeks to months after the injury.
Personality Changes / Self-Isolation
Many may suffer personality changes because of frontal lobe damage and become quite irritable and easy to anger. The person who wakes up after the injury often does not have the ability to express what is wrong with them, may not recognize much of it or deny it, becomes embarrassed when they cannot carry on a conversation, work at their previous job, or do the same activities that they used to handle. As a result, many self-isolate, withdrawing from church, friends and other activities. Friends, family and co-workers, who see the same external person, may not understand why the survivor is so different. Friends soon stop coming by or asking them to participate in activities. Families who are not committed to each other break up. Obviously, depression becomes a big problem for people who have changed so much and lost so much. Suicide is something that almost all severely injured people have thought about at one time or another. Occasionally, those who do not have access to medical care or who do not understand what is happening may self-medicate with alcohol and other drugs, particularly those who have previously sought solace with these compounds. It is very important that the family and friends of the survivor maintain supportive contact even though it requires an adjustment in their relationship with the survivor. An injury such as this is an injury to the family, not just to the person hit.
Fatigue
Survivors often complain of easy fatigability, becoming exhausted after only a few hours of work. This may be because every task that they used to automatically do without thinking now requires intense concentration to accomplish. Many return to work but find that they cannot multitask and do all of the activities that are required at their job.
Medical Testing
There are two kinds of medical tests: anatomic tests take a simple picture (x-ray) or measurement (blood count) functional tests show how something is working (PET, neuropsychological testing) Sometimes function can be ascribed to the anatomic tests but often it cannot. The mental changes of a lightning survivor are functional (how the brain works) changes, not anatomic ones so that anatomic tests such as the CT scan and MRI are usually normal. More functional scans such as PET and SPECT may show changes but are hard to obtain due to their relative infrequency in medical centers. To use an analogy: if an electric shock were sent through a computer, the outside case would probably look ok (similar to a photo or x-rays of the person), the computer boards on the inside would probably look ok and not be fused nor melted (CT, MRI for the person), but when you boot up the computer it would have difficulty accessing files, making calculations, printing, etc. This situation is similar to a person with brain injury who has short term memory problems, difficulty accessing and coding information, difficulty organizing output, etc. A functional test of how a person's brain is working that is seldom thought of by most non-neurologists is called neurocognitive or neuropsychological testing. These tests are administered by a qualified neuropsychologist familiar with the literature in this area, not by a psychiatrist, and consist of a 6-8 hour battery of pen and paper tests including memory, IQ, organizational ability, and other how the parts of the brain are working' kinds of tests. Survivors of lightning and electrical injury usually have a characteristic pattern of deficits.
Delayed Problems
Another common, but often delayed, problem for some survivors is pain, also a difficult problem to quantify and manage. The pain may not be from chronic intense headaches but may be in the back (perhaps from compression and disc injury from the intense muscle contractions which may throw a person several yards at the time of the injury), or in an extremity. Some may have nerve entrapment syndromes and a small number may eventually develop Sympathetically Mediated Pain Syndrome.
Sometimes the Right Rest Is Not Available
Sometimes the functional tests that are ordered are testing the wrong thing; an electromyogram (EMG) measures only the largest nerve fibers, the motor fibers, which are seldom affected by lightning injury. Smaller pain carrying nerve fibers are not tested by EMG, so that a normal EMG means little when ordered for someone with pain. Likewise, the standard EEG measures primarily surface readings of the brain and misses seizure activity in several deeper regions. Decreased libido and impotence are often reported.
Help Exists - Lightning Strike and Electric Shock Survivors, International, Support Group
An organization that has been of tremendous help to survivors, their families, their physicians and other professionals is Lightning Strike and Electric Shock Survivors, International (LSESSI), a support group formed in 1989 by a gentleman who was injured in 1969 who became tired of no one recognizing or knowing what to do for those with lightning injury. LSESSI has printed materials, offers tremendous support, networks survivors with others in their area, and provides an annual meeting where survivors come together for support as well as for lectures from professionals who work with lightning and electrical survivors and their families. LSESSI can be reached at 910-346-4708, Lightnin@nternet.net, http://www.lightning-strike.org/index.html, or at P.O. Box 1156, Jacksonville, North Carolina 28541-1156.
Four Factors Necessary for Recovery
The four most important factors in overcoming disability from lightning injury (or from any illness or major injury for that matter) are: 1. A supportive family / friends network. 2. The person or family becoming their own best advocate and learning as much as they can about their disability. 3. A physician (regardless of specialty) who is willing to listen, read, learn and work with the survivor and their family. 4. A sense of humor.
Prevention
Far more important than treating survivors is preventing lightning injury. All of the people who have worked on this first National Lightning Safety Awareness Week have as their greatest hope that it will have helped you and your family learn how to avoid injury. Prevention is the KEY. This fact sheet courtesy Dr. Mary Ann Cooper - Associate Professor, Departments of Emergency Medicine and Bioengineering University of Illinois at Chicago.
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