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HOW MANY PEOPLEARE KILLED BY
LIGHTNING EACH YEAR?
by MARTIN A. UMAN
ORIGINALLY PUBLISHED IN
ALL ABOUT LIGHTNINGDOVER PUBLICATIONS, NEW YORK, 1986
ORIGINALLY PUBLISHED IN
ALL ABOUT LIGHTNINGDOVER PUBLICATIONS, NEW YORK, 1986
HOW MANY PEOPLEARE KILLED BY
LIGHTNING EACH YEAR?
by MARTIN A. UMAN
Although no exact figures on lightning fatalities are available— there is no central agency to which lightning accidents mustbe reported—various studies (Refs. 3.1, 3.2, 3.3, 3.4) haveplaced the average annual number of deaths in the U.S. at 100,137, 151, 300, and even 600. Whatever the exact number, light-ning causes more direct deaths than any other weather phe-nomena. Snowstorms cause more indirect deaths (e.g., heartattacks from shoveling the driveway). Tornadoes cause abouthalf as many deaths as lightning but inflict much more prop-erty damage. It is perhaps surprising that about two-thirds ofthe people involved in lightning accidents subsequently make acomplete recovery. Most, if not all, of these survivors are prob-
ably not directly struck by lightning, but rather receive electri-cal shock from being in the close vicinity of a strike.
About 70% of all fatal lightning accidents involve one per-son, about 15% occur in groups of two, the remainder involvesthree or more deaths per lightning event. Between 75 and 85%of all lightning deaths and injuries are to men, probably be-cause they are more likely to be out-of-doors. About 70% of allinjuries and fatalities occur in the afternoon, about 20% be-tween 6 p.m. and midnight (Ref. 3.1).
The largest single category of lightning deaths (12 to 15% ofall fatalities) is composed of those unfortunate individuals whoseek refuge under trees during thunderstorms and have theirsheltering trees struck by lightning. Perhaps one-third of theseare golfers. Two additional categories in which large numbersof lightning fatalities occur are designated “Open Water” and“Tractors”, each claiming about 10% of the total fatalities.“Open Water” includes people fishing, swimming, on beaches,piers, and levees, in boats, and on water skis; “Tractors” in-cludes people on, in, or near farm tractors or other implements,construction equipment, cars, and trucks (Refs. 3.1, 3.3).
Most lightning deaths occur outdoors. Over 30% of all light-ning deaths involve people who work outdoors; over 25% ofall deaths involve outdoor recreationists. A breakdown of deathsand injuries to farmers and ranchers and to outdoorrecreationists for the 20-year period 1950 through 1969 is givenin Table 3.1. The apparent increase from the 1950s to the 1960sin the number and percentage of deaths to outdoor recreationistsis perhaps due to the increasing number of outdoorrecreationists. Table 3.2 gives more detailed data on death andinjury to outdoor recreationists, while Table 3.3 breaks downthe “Open Water” category of Table 3.2.
In addition to humans, animals are killed by lightning. In1968, lightning caused the death of 464 cattle (362 killed di-rectly, the remainder by lightning-caused fires), 13 horses (11killed directly), 42 hogs, 2 dogs, and 1 white ox resident in amuseum pasture (Ref. 3.4).
From the foregoing it is obvious what you should not dowhen out-of-doors during a thunderstorm: do not make a light-
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Tab
le 3
.1: D
eath
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om li
ghtn
ing
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he c
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nite
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ates
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otal
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equa
ls t
he s
um o
f C
olum
ns 5
, 9, 1
3 an
d 17
.
ning rod of yourself and do not stand beneath a lightning rod.Avoid projecting above the surrounding landscape, as you woulddo if you were standing in an open field, on the beach, or fish-ing from a small boat. Avoid standing under isolated trees orunder any other isolated shelters. (Potentially dangerous sunand rain shelters are often provided on golf courses.) Stay awayfrom wire fences, overground pipes, rails, and other metallicpaths along the ground which could carry lightning currents toyou from a stroke which has hit some distance away. Avoidswimming, since the current from a nearby stroke to the watercan flow through the water to you.
Here’s what you should do if caught out-of-doors during athunderstorm. In an urban area, seek shelter in a building (pref-erably with metal frame and/or with a lightning rod system) orin a car (not a convertible) with the windows rolled up (seeChapter 4). In the wide-open spaces, find a ravine, valley, or, asa last resort, a depression in the ground. Crouch or lie down. Ina wooded area, seek shelter in dense woods or among a thickgrowth of small trees.
Relatively few people are killed indoors by lightning. Thegreatest number of indoor deaths is probably due to lightning-caused fires. Nevertheless, between 1959 and 1965 four peoplewere reported killed by lightning while using their telephones(Ref. 3.1); many others were killed because they were near, orin contact with, fixtures connected to the house plumbing orto appliances that were plugged into the house wiring system.
When lightning strikes a house without a lightning rod sys-tem, the lightning current generally follows the water pipes andelectrical wiring in an attempt to get to ground. It may alsoenter a house on the telephone or electric wires or on the lead-in wires from an exterior TV antenna. (The mast to which anexternal TV antenna is attached, and from which it is electri-cally isolated, should be well connected to ground in accordwith the codes for lightning rod systems.) If the particular con-ductor in which the current is traveling is not well-connectedto ground, the lightning may choose to leave that conductorand jump through the air to what it regards as a better path toground. The trip through the air, or side flash, accounts for a
significant fraction of indoor lightning fatalities (as well as be-ing one of the ways in which people standing beneath light-ning struck trees can be killed). Thus during a thunderstorm itmakes good sense to stay far away from bath tubs, sinks, plugged-
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* Includes sightseers, recreation strollers, youths at play (except athletics) anywhere outdoors, and others.** Persons identified by data source as having been at recreation areas at time they were struck, with nospecific activity indicated.
Table 3.2: Known lightning deaths and injuries among outdoorrecreationists in the 48 contiguous United States during 1950–1969 (Ref. 3.4)
Table 3.3: Analysis of “In, on, or near open water” in Table 3.2(Ref. 3.4)
* Mostly persons on lake or ocean shores or stream banks and persons whose activities were listed in thedata sources only as “fishing” with no indication as to whether they were on shore or in a boat.
in appliances, telephones, or any objects that have a metallicconnection with the outside.
Telephone and electric companies attempt to design systemswhich discourage lightning from entering houses via their wires.A “lightning protector” (costing about $50, excluding installa-tion) on the main circuit breaker or fuse box will short-circuitto ground lightning current attempting to enter a house on theelectric wires. A similar “lightning protector” is sold for TVlead-in wires. Protection of your house against direct lightningstrikes can be accomplished with a lightning rod system (Chapter2) at a cost of several hundred dollars (including installation).If lightning does enter electrical wiring, it can cause consider-able damage to plugged-in appliances. Although it is safest tounplug all appliances before a thunderstorm, this is somewhatimpractical. For a typical urban house in a region of moderatethunderstorm activity, say Pennsylvania or New York (see Chap-ter 7), the frequency of strikes to the house is statistically aboutonce every hundred years (see Chapters 6 and 7). Saying thesame thing another way, one in every hundred houses is hiteach year.
Lightning “deaths” are often reversible. Many victims whoappear dead, in that they are not breathing and have no heartbeat, can be revived with proper first aid (Ref. 3.5). It is tragicthat this fact is not more widely known. If a victim is still breath-ing, he will, in all probability, recover.
Often, when a person is involved in a lightning accident,heart action and breathing stop instantly. There is medical evi-dence that all metabolism seems to stop (Ref. 3.5). Typicallythe heart starts again, but respiration does not. If the victimdoes not breathe for a prolonged period, he suffers brain dam-age from lack of oxygen. The apparent stopping or slowing ofmetabolism can seemingly lengthen the usual five or six-minuteperiod before appreciable brain damage occurs. A case was re-ported in which the victim apparently did not breathe for be-tween 13 and 22 minutes, and still made an essentially com-plete recovery (Ref. 3.6).
If the victim’s heart has started spontaneously but his breath-ing has not, his airway should first be cleared and then mouth-
to-mouth artificial respiration given at about one breath every5 seconds. If his heart is not beating (if the victim has no pulse),both heart action and breathing must be restarted. Heart ac-tion can be stimulated by placing the victim on his back andpressing firmly on his chest (on the lower half of the sternumabove the point where the ribs come together) with the heel ofthe hand once every second or slightly faster. A person alonewith the victim should alternate between 15 chest compres-sions and 2 mouth-to-mouth respiration cycles. If two rescuersare present, one should compress the chest at a steady rate ofonce per second while the other gives one breath every fivecompressions timed so that the breath is going in as the handsare coming up. This first aid should be continued until thevictim’s heart action and breathing begin or until professionalmedical help is secured. The above is only a brief explanationof the rudiments of cardio-pulmonary resuscitation (CPR) andis no substitute for a proper education in these life saving pro-cedures (Ref. 3.7).
REFERENCES
3.1. Zegel, F. H., Lightning Deaths in the United States: ASeven Year Survey from 1959 to 1965, Weatherwise, 20, 168-173, 179, August 1967.
3.2. U.S. Dept. of Commerce, ESSA, Lightning, 1966, U.S.Government Printing Office, Washington, D. C.
3.3. Metropolitan Life Insurance Company, Statistical Bul-letin, 33, 8-10, June 1952.
3.4. Unpublished analysis by Alan R. Taylor, Northern For-est Fire Laboratory, USDA Forest Service, Missoula, Montana.Analysis based on data published in Climatological Data, Na-tional Summary, U.S. Department of Commerce, WeatherBureau, Vols. 1-9, 1950-58, and Storm Data, U.S. Departmentof Commerce, ESSA, Vols. I -11, 1959-69.
3.5. Taussig, H. B., “Death” from Lightning and the Possi-bility of Living Again, American Scientist, 57 (No. 3), 306-316 (1969).
3.6. Ravitch, M. M., R. Lane, P. Safar, F. M. Steichen, and P.Knowles, Lightning Stroke, New England Journal of Medicine,264, 36-38 (1961).
3.7 Red Cross, Red Cross CPR Module, The American RedCross, 1980.
ADDITIONAL READING
Golde, R. H., and Lee, W. R., Death by Lightning, Proc.IEE, 123, 1163-1179, October 1976.
Cooper, M. A., Lightning Injuries: Prognostic Signs forDeath, Ann. Emerg.Med., 9, 134-138, March 1980.
Storm Data, Volume 25, No. 12, December 1983, availablefrom Publications Section(E/CC413),the National ClimaticData Center, NOAA, Federal Building, Asheville, N.C. 28801-2696. Contains lightning death and injury statistics by monthand by state for the United States from 1959 to 1983.
THE EVENT
PETRIFIED LIGHTNING FROM CENTRAL FLORIDA
A PROJECT BY ALLAN MCCOLLUM
CONTEMPORARY ART MUSEUMUNIVERSITY OF SOUTH FLORIDA
MUSEUM OF SCIENCE AND INDUSTRYTAMPA, FLORIDA