From various sources some statistics were collected.
Here we can have look at it.
Somebody tells it will strike only at the highest points.
But here are the facts
- 2 engineers died while inspecting road construction in South India.
- A boy was struck by lightning in a foot ball field.
- Weigh bridges often damaged in the iron ore field at Goa.
- Parents killed but 3 children injured when they sought shelter under an isolated tree.
- 3 men struck by lightning when they install chain link fencing.
- Lightning struck on a man to death when walking in the open ground leaving 3 persons standing under a tree nearby.
- 2 Caddies died of lightning in a golf course.
So virtually anything can be struck by lightning.
Also the place, intensity and destruction potential can not be predictable.
- Lightning will travel at a speed of 1 meter per microsecond.
- 70% of the discharges are inside the clouds: intra-cloud (most common) or inter-clouds.
- Max 30% of the discharges are developing between the cloud base (negatively charged usually) and the ground.
- Lightning protection will discharge very high current upto 100 kA (Kilo Amperes). In Japan 200 kA also recorded.
But to the surprise only 25% of the victims only die. According to an U.S. data 85% percent of lightning strike victims are children and young men (10 to 35 years old) when they are at work.
Lightning damage probability is more in summer and 70% of strikes happen between June & August.
Another fact about lightning is it will struck between 2 p.m to 6 p.m.
There must be a science behind the characteristics of lightning which could not be understood fully by humans till this day. Research is still going on.
Still it is a puzzle that 11 players of one team of a football game struck by lightning and the other team members untouched.
Somebody says lightning strike will not strike twice at the same place but the Empire state building was struck 25 times.
The following are the unsafe areas at the time of Lightning
- Small structures including huts & rain shelters
- Nearby metallic objects like fences, gates, instrumentation and electrical equipments, wires and power poles.
- Avoid isolated trees, water, open fields, using telephones
- Avoid being in or near high places like tanks, towers or stacks
- Avoid talking in telephone, taking shower, electrical wiring or cable TV wiring inside the house.
The following are the safer places to take shelter
- Large metal framed and enclosed structures
- All lightning protected buildings
- Fully enclosed metal vehicles (not touching the metal surface)
- Underground tunnels, caves
- Streets shielded by nearby buildings
Tips to take precautions at the time of Lightning
- If you hear thunder, suspend all outdoor activities
- If you see lightning, seek a shelter immediately
- Those who are working at heights, climb down take shelter in a protected building
- Depend upon Radio to keep updated of weather conditions
Lightning discharge consequences on human beings
- Burns: By arc or by flash if the lightning stays in surface; in that case, the consequences are rarely severe.
- Neurological effects: Coma is not rare; it can be either superficial or profound. Amnesia of the accident is frequent. It is due to the bypassing of lightning through the encephalic structures. After effects are frequent (hemiplegia, cortical atrophy, epilepsy, extra pyramidal syndrome, spinal and peripheral nervous lesions).
- Cardio-vascular lesions: Circulatory arrest happens by asystolia or ventricular fibrillation. A direct myocardic lesion by Joule effect, a myocardic contusion by the shock wave, a thrombosis of the coronary or peripheral arteries can also be seen.
- Respiratory lesions: it can be a tetanization of the respiratory muscles for a short time, a direct lesion of nervous centres, a bronchial or pleural rupture, or a lesion of the alveolo-capillar membrane when the over-heated air explodes (blast).
- Neuro-sensory effects: ocular lesions due to retinal detachment and potential cataracts must be screened for. Auditory lesions including tympanic membrane rupture and balance impairments as a consequence of labyrinth damage can also occur.
- Muscular effects: extensive muscular breakdown with deep necrosis and rhabdomyolysis may occur along the pathway of conduction.
- Renal effects: there are mainly three consequences: tubular pathology due to the muscle lysis (early fluid balance is vital); parenchymal lesions due to arterial thrombosis; traumatic lesions.
- Cutaneous lesions: burns of all severities, in particular at the points of lightning entry (restorative surgery is frequently required) and at points in contact with metal (climbing equipment, jewellery); fernlike patterns are classic (Lichtenberg bodies)
Lightning damages to structures
For non-metallic structures, the lightning current is using the most conductive paths to earth which are usually the most humid components such a stones joints … In such case, the heat and extra-pressure created by the lightning current flowing down to earth can cause an explosion of the structure.
The phenomenon is similar for trees struck by lightning: tree sap conducts the lightning discharge. Along the path of the strike, sap boils and the gas in the wood expands, often with explosive consequences. If only one side of the tree shows the evidence, a stripe spiralling from top to bottom, the chances of the tree surviving and eventually closing the wound are good. Trees are usually killed when the strike passes completely through the trunk, leaving a path of splintered bark on each side.
Lightning current will always enters buildings through the most conductive paths, ie. metallic pipes or wires (water pipes, electrical/telephone wires…), devastating all the connected equipments and igniting fires.
Being aware of lightning hazards is a big step towards Lightning Safety
Nature will give warning by the pre-cursors of high winds, cloudy sky and heavy rainfall. Many casualties occur because people ignores these pre-cursors
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