Lightning safety has been little studied and less practiced. In ancient times thunder and lightning were audible and visible signs of the gods' displeasure: there was no defense whatsoever (1). In present times more than 45 different USA lightning protection codes (2) promulgate ambiguity and confusion concerning reduction of the hazard. Current lightning studies are focused mainly upon its physical aspects. Atmospheric physicists, electrical engineers, meteorologists and other skilled disciplinarians probe the behavioral complexities of various sectors. At the same time, business enterprises (3) and trade organizations (4) offer proprietary protection designs. These may be incomplete, misleading or unsubstantiated. There is no Utopia in lightning safety. The dearth of objective data about lightning safety contributes to accidents and injuries. Common misconceptions include: "Lightning never strikes twice in the same place" and "Lightning rods prevent lightning strikes." The ignorance and misinformation about lightning safety increase lightning's social cost in deaths and injuries and economic cost in electrical and electronic damage, explosions, fire, etc. A disciplined and systematic approach to lightning safety may result in better management of the hazard and reduced costs.
Official US weather bureau lightning death and injury statistics have been challenged for two decades. Weigel's 1976 study put under-reporting at 50% (5). In 1993, Lopez, et al. examined Storm Data records for Colorado for a 12 year period and compared these with Colorado Health Department and Colorado Hospital Association information for the same duration. They found that Storm Data had under reported deaths by 28% and injuries that required hospitalization by at least 42% (6). While accurate data is elusive, there is general agreement that lightning is one of the leading weather-related cause of deaths and injuries.
Table 1. Annual average severe weather fatalities by decade from 1940-1991, National Weather Service, 1992. (7)Year Lightning Tornado Flood Hurricane 1940-1949 337 154 144 22 1950-1959 184 135 79 87 1960-1969 133 94 121 59 1970-1979 98 99 182 21 1980-1989 72 52 110 12 1990-1991 73 46 102 8 _______________ ____ ____ ____ ____ Total (51 yrs.) 8316 5731 5828 2031
Eighty five percent of lightning victims are children and young men ages 10-35 engaged in recreation or work. Twenty percent of strike victims die and 70% of survivors suffer serious long-term after effects (8). Beyond this an unknown number of injuries do not require hospitalization.
Englestatter's 1994 definitive psychological study (see Table 2, below) describes some symptoms suffered by twenty five percent or greater of lightning strike victims (9).
Table 2. Lightning strike victims sequelae, frequency 25% or greater. * Denotes Psychological ** Denotes Psychological or Organic No Asterisk Denotes OrganicMemory Deficits & Loss 52% ** Depression 32% * Attention Deficits 41% ** Inability to Sit Long 32% Sleep Disturbance 44% * External Burns 32% Numbness/Parathesias 36% ** Severe Headaches 32% ** Dizziness 38% * Fear of Crowds 29% * Easily Fatigued 37% * Storm Phobia 29% * Stiffness in Joints 35% Inability to Cope 29% * Irritability/Temper Loss 34% * General Weakness 29% ** Photophobia 34% Unable to Work 29% ** Loss of Strength/Weakness 34% ** Reduced Libido 26% * Muscle Spasms 34% Confusion 25% ** Chronic Fatigue 32% * Coordination Problems 28% ** Hearing Loss 25%
Despite the magnitude of lightning's effects on people, major federal disaster relief and safety organizations such as Federal Emergency Management Agency (FEMA) and Occupational Safety and Health Agency (OSHA) have few provisions for personal lightning hazard education, standards, or training (10).
PJ Duclos of the Centers for Disease Control concluded in a 1989 public health study of lightning-related deaths: "Making the public, particularly those in high-risk professions and those who are frequent users of high-risk recreational areas, aware of these [safety] measures through the media and publicity campaigns, is necessary to decrease the annual number of injuries and deaths from lightning strikes." (11)
Lightning-caused property loss statistics vary widely according to source. Federal and State government agencies do not disclose damage or losses from lightning events at their facilities. Storm Data compiled lightning-related private sector property damage costs for the 1990-1992 period at $27 million annually (12). This data was obtained from newspaper clippings. The National Fire Protection Association (NFPA) reported direct annual structural lightning losses at $138.7 million as averaged over 1989-1993 (13). This information came from the nation's fire chiefs, who also reported 20,000 lightning-caused residential fires.
Holle et al. (1995-homeowners only) analyzed lightning claim costs reported by State Farm Insurance Co. in Colorado, Wyoming and Utah. These were extrapolated to national figures. This finding showed there to be 307,000 separate lightning claims totaling $332 million annually (14). A fourth source, the Insurance Information Institute, described national lightning damage amounting to nearly five percent of all paid insurance claims, with residential claims alone exceeding one billion dollars during 1990 (15).
Commercial claim costs are higher than those for residences. The Factory Mutual System reported 2,926 lightning claims in the 1973-1982 period, for a total cost of some $385 million. Average per claim cost was in excess of $13,000 (16). Lost time from an idle workforce was not included therein. Statistical accuracy notwithstanding, the direct and indirect effects of lightning to electrical and electronic equipment are significant, and there is little recognition of the problem. The insurance industry provides an interesting example. It widely promotes policy cost discounts for use of deadbolt locks, fire extinguishers, security alarms, smoke detectors, etc. In contrast, there are no equivalent incentives for use of surge protectors by the insured to protect sensitive electronic equipment. Insurance companies could act as agents of change here, with a benefit to them of considerable savings in paid-out claims.
The rapid growth of silicon-based, microprocessor-controlled devices across our society will accelerate costs and losses so long as adequate lightning protection measures are not adopted as a standard practice.
A strong case can be made for reducing lightning's human and economic costs through the adoption of pro-active defensive guidelines. Research which defines accurate cost and loss figures is vital to this objective.