Lightning strike: cruelty of nature

Useful facts for humans:

Human has dreadful as well as amazing experience of perceiving lightening. Several reports indicated that thousands of people are hit by lightning each year, only a fraction are seriously injured.

A lightning strike is a huge electrical discharge between the atmosphere and an earth-bound object. A lightning bolt can heat the surrounding air to 50,000 degrees Fahrenheit—that’s five times hotter than the sun—and can contain up to 300kV of energy.

To understand lightening, it is elaborated that lightning is an unexpected electrostatic discharge during an electrical storm between electrically charged regions of a cloud (called intra-cloud lightning or IC), between that cloud and another cloud (CC lightning), or between a cloud and the ground (CG lightning). The charged areas in the atmosphere temporarily balance themselves through this discharge denoted to as a strike if it hits an object on the ground, and a flash if it occurs within a cloud. Lightning causes light in the form of plasma, and sound in the form of thunder.

Injuries due to lightening:

Serious lightning injuries involve primarily cardiac arrest and neurologic injury in developed countries. Major complications are rare in mild and moderate lightning injuries, although musculoskeletal discomfort and subjective sensations of paresthesias, irritability, and other nonspecific neurologic sequelae may be present, depending on the location and intensity of the strike. In severe lightning injury with cardiopulmonary resuscitation (CPR) required in the field, permanent neurologic deficit and hypoxic injury are common.

Complications of being struck by lightning are as under:

Ø  Chronic pain syndromes

Ø  Neuromuscular pain

Ø  Neurocognitive deficits, including short-term memory loss, difficulty accessing or processing new information, attention deficit, personality change, distractibility, or loss of ability to multitask

Ø  Isolation or depression

Ø  Sympathetic nervous system dysfunction, including positive tilt tests and hypertension

Ø  Dizziness

Ø  Sleep disorders

Ø  Symptoms similar to postconcussion syndrome (eg, headaches, nausea, confusion)

Ø  A typical seizure disorders

Ø  Pituitary or hypothalamic damage with secondary endocrine effects

Cardiopulmonary complications include the following:

Ø  Transient hypertension

Ø  Electrocardiographic changes

Ø  Myocardial injury

Ø  Congestive heart failure

Ø  Dysrhythmia

Ø  Transient asystole

Ø  Atrial fibrillation

Ø  Ventricular fibrillation

Ø  Frequent premature ventricular contractions

Ø  Respiratory complications

Ø  Apnea

Ø  Hypoxemia

Lightning injuries also causes Damage to the central nervous system (CNS). Neurologic complications include the following:

Ø  Immediate loss of consciousness

Ø  Amnesia and confusion

Ø  Retrograde amnesia

Ø  Hemiplegia, aphasia

Ø  Coma

Ø  Seizures

Ø  Intraventricular hemorrhage

Ø  Hematomas

Ø  Keraunoparalysis

Vascular complications include the following:

Ø  Vasomotor instability

Ø  Arterial spasm

Ø  Vasoconstriction

Ø  Vasodilatation

Ophthalmic complications include:

Ø  Cataracts

Ø  Macular holes

Ø  Corneal lesions

Ø  Hyphema

Ø  Iritis

Ø  Vitreous hemorrhage

Ø  Retinal detachment

Ø  Optic nerve injury

Otologic complications are as under:

Ø  Ruptured tympanic membrane

Ø  Temporary hearing loss

Ø  Disruption of the bones of hearing

Ø  Dizziness and instability from eighth nerve damage

Prevention system for lightning:

Conventional lightning protection systems guard buildings, equipment, and people from lightning strikes through lightning Arrester to attract the lightning and conduct the resulting surge current to ground via a dedicated grounding wire. Nevertheless, the associated electromagnetic pulse (EMP) can cause a surge current to flow through electronic devices in the building, resulting in damage to equipment.

Use of conventional lightning protection systems based on lightning rods may result in destruction to vulnerable electronic and IT equipment when a lightning strikes which produces induced currents.

The new Dissipation Array lightning protection system averts lightning damage by inhibiting the lightning strikes themselves. The new lightning prevention system comprises of a hemispherical ionizer formed from wires to which a large number of protruding rods have been welded. It is installed at the highest point on the building being protected and connected electrically to a ground current collector buried in the ground. The electric field that forms between the bottom of the thunder cloud and ground causes a corona discharge at the tips of the ionizer rods, positively ionizing the surrounding atmosphere. In the case when the bottom of the thunder cloud is negatively charged, the ionizer rods positively ionize the surrounding atmosphere, weakening the electric field in the direction of the earth. This prevents lightning strikes by inhibiting the creation of upward leaders from the ionizer, thereby minimize the risk of connection with downward leaders from the thunder cloud. The new lightning prevention system has been installed at more than 4,000 sites in 57 different countries around the world (as of December 2010).

The three-dimensional (3D) lightning monitoring system uses three sets of antennas to detect radio waves emitted by the progression of lightning discharges, and uses the phase difference between them to determine the direction of the discharges. By monitoring from a number of locations, the system can also determine the 3D coordinates of discharges. The system uses a very high frequency (VHF) broadband digital interferometer.

Ways to escape or survive in lightning strike (Preventive measures):

In the occurrence of lightening, people must take some steps to lower chance of getting affected. These safety procedures are recommended by the National Weather Service:

- When a thunderstorm threatens, get inside a home or large building, or inside an all-metal (not convertible) vehicle.

- Inside a home, people must not use mobile or telephone, except for emergencies

If outside, with no time to reach a safe building or an automobile, People can follow below rules:

- Do not stand under a natural lighting rod such as a tall, isolated tree.

- Avoid projecting above the surrounding landscape as people would do if they were standing on a hilltop, in an open field, on the beach, or fishing from a small boat.

- Get out of and away from open water.

- Get away from tractors and other metal farm equipment.

- Get off of and away from motorcycles, scooters, golf carts and bicycles. Put down golf clubs.

- Stay away from wire fences, clotheslines, metal pipes, rails and other metallic paths which could carry lightning to you from some distance away.

- Avoid standing in small isolated sheds or other small structures in open areas.

If people are in a forest, they seek shelter in a low area under a thick growth of small trees. In open areas, go to a low place such as valley.

To bind up facts, it is established that lightning occurs due to an electrical discharge of electrons moving very quickly from one place to another. These electrons move so quickly that they superheat the air around them causing it to glow.  World statistics indicates that Lightning strikes kill thousands of people worldwide each year. People must take precautions to keep themselves safe.

Important note: This article is based on available information. Writer is not responsible for any disagreement.