and Injuries from Lightning in the UK

Transcription

1 Documenting 25 Years of Deaths and Injuries from Lightning in the UK Derek M Elsom 1, Jonathan D C Webb 2 1 Oxford Brookes University & Tornado and Storm Research Organisation (TORRO) 2 TORRO Paper presented at the Royal Meteorological Society s Second Amateur Meteorologists Conference, University of Reading, 14 September 2013 Contact details: Professor Derek M Elsom at dmelsom@brookes.ac.uk

2 Database To assess the lightning risk to people in the UK, a 25-year database ( ) was compiled of incidents when people experienced an electrical shock due to lightning Indirect lightning incidents are excluded e.g. being struck by falling masonry when a building is struck; suffering burns when lightning starts fires

3 Database results 443 known incidents 720 people affected, as many incidents resulted in more than one person experiencing i an electrical shock Annual A l average = 29 people but actual number may be double? Broad locations of incidents: Outdoors = 52% (73% male) Indoors = 47% (49% male) Inside a motor vehicle or aircraft = 1%

4 Severity of injuries? Potentially lethal high-voltage electric current but has contact with a person for only milliseconds Serious injuries (cardiopulmonary arrest, full thickness burns) may result if a significant part of current penetrates the body Minor injuries if surface flashover effect dominates i.e. current passes over the skin & clothes, especially if wet

5 Lichtenberg Figures: fern-like pattern (fractal pattern of repeated bifurcations) of skin reddening (not a burn) caused by electrons Merthyr Tydfil, 2011 (below) Source: Gear Diary (2011) Source: Wales Online (2011) Source: Mahajan et al. (2008)

6 Thermal burns from metal objects Carrying small metal objects (e.g. necklace, keys, coins) does not make you more likely to be struck but may leave thermal (heat) burns Moisture in sweaty parts of the body may vapourise instantly tl leaving burns. On rare occasions, sweaty feet & tight-fitting footwear may cause socks & shoes to be torn apart Swedish 16-year-old girl s football boots after she was struck, August Neck chain burn, Preseli Mountains, Wales 25 th November Source: Condron, 2005 Source: The Times, 1994

7 A Lightning s potential to injure B C E D F Subsequent discharge from insulated object G Pressure or shock wave H Indirect effects (non-electrical) Source: Cooper et al. (2007)

8 Outdoor incident locations Category % of total incidents Apportioning near a tree Near or under a tree 16 - Mountain, hill, moor, cliff top Low-lying farm land or country 5 6 Golf course Sports or recreation ground Urban setting (street, car park, lawn) excl. above cats Near, in or on water Other e.g. airfield 4 4

9 Aylesford 2 nd Sept people sheltering under a tree, some under a large umbrella 3 resuscitated t incl. boy with 18% burns 8 discharged after hours 3 with paraesthesia ( weeks) Many with tiny punctuate burns on the tips of toes Source: Fahmy et al. (1999) Source: The Times, 1996

10 Indoor incident locations Near or touching % of total t incidents Telephone 26 Computer equipment 5 Electrical equipment e.g. circuits & sockets, television, kettle, iron 13 Window or external door 15 Large object with metal pipes e.g. 15 radiator, sink, shower, bath Other (e.g. in bed) or unspecified 25

11 Lightning effects on people Medical effects Outdoors Indoors Death 21% 0% Cardiopulmonary arrest but 7% 0% resuscitated (CPR successful) Serious burns; brief 16% 2% unconsciousness; severe fractures Minor burns; temporary damage to eardrums or eyes; knocked k off feet causing minor blunt trauma; temporary numbness or pain in shoulder, arm or leg; minor electrical shock 56% 98% Longer-term effects not included d but may be serious in some incidents id

12 Fatalities 47 deaths in 25 years but 15 other incidents included someone who had to be resuscitated Only one incident with more than one death: two women sheltering under a tree at Hyde Park, London, on 22 nd September 1999 Average annual fatalities: UK: = 2 people (83% male) England & Wales only (source : Elsom, 2001): = 5 people (84% male) = 13 people (89% male) = 19 people (82% male)

13 Conclusion: lightning i risk awareness Month % of all incidents % of fatalities May 14% 21% June 19% 17% July 25% 15% August 19% 26% Total 77% 79% Need for all-year-round public and educational lightning risk awareness information but give particular prominence during the first thunderstorms in May?

14 References and sources Condron, S. (2005) Alive! Boy hit by lightning. Daily Mail, December 17, 2005, p.37 Cooper, M.A. et al. (2007) Lightning injuries. In Wilderness Medicine. Auerbach, P.S. (ed), 5 th edition, Mosby Elsevier, pp Elsom, D.M. (2001) Deaths and injuries caused by lightning in the United Kingdom: analyses of two databases. Atmospheric Research, 56, Fahmy, F.S. et al. (1999) Lightning: the multisystem group injuries. Journal of Trauma: Injury, Infection & Critical Care, 46, Gear Diary (2011) Mahajan, A.L. et al. (2008) Lichtenberg figures: cutaneous manifestation ti of phone electrocution from lightning. J. Plastic, Reconstructive & Aesthetic Surgery, 61, The Times (1994) Soccer girl s lightning recovery. The Times, August 10, 1994 The Times (1996) Record lightning strike left strange marks on skin. The Times, February 12, 1996 Wales Online (2011)