Lightning strikes can produce severe injuries, and are lethal in between 10 and 30% of cases, with up to 80% of survivors sustaining long-term injuries. People caught in such extreme situations – without having been able to flee to a safer, fully enclosed space – are advised to assume the 'lightning position', which involves 'sitting or crouching with knees and feet close together to create only one point of contact with the ground' (with the feet off the ground if sitting if a standing position is needed, the feet must be touching). Warning signs of an impending strike nearby can include a crackling sound, sensations of static electricity in the hair or skin, the pungent smell of ozone, or the appearance of a blue haze around persons or objects ( St. Visual artefacts may be induced in the retinas of people located within 200 m (650 ft) of a severe lightning storm.

EMPs – the discharge process produces an electromagnetic pulse ( EMP), which may damage an artificial pacemaker, or otherwise affect normal biological processes.This phenomenon (also responsible for reports of mass reindeer deaths due to lightning storms) leads to more injuries and deaths than the above three combined. The near-instantaneous rate of discharge causes a potential (difference) over distance, which may amount to several thousand volts per linear foot. Because the ground has high impedance, the current 'chooses' a better conductor, often a person's legs, passing through the body. Ground current or 'step potential' – Earth surface charges race towards the flash channel during discharge.

Blast injuries – being thrown and suffering blunt-force trauma from the shock wave (if very close) and possible hearing damage from the thunder.

Side splash – branches of currents 'jumping' from the primary flash channel, electrify the person.

Contact injury – an object (generally a conductor) that a person is touching is electrified by a strike.

Depending on the flash strength and access to medical services, it may be instantaneously fatal or cause permanent injury and impairment. Enormous quantities of energy pass through the body very quickly, resulting in internal burns, organ damage, explosions of flesh and bone, and nervous system damage.

Direct strike – the person is part of a flash channel.

Lightning strikes can injure humans in several different ways: The entire flash lasts only a fraction of a second. Lightning discharges are typically miles long, but certain types of horizontal discharges can be tens of miles in length. The primary conducting channel, the bright, coursing light that may be seen and is called a 'strike', is only about one inch in diameter, but because of its extreme brilliance, it often looks much larger to the human eye and in photographs. Most CG flashes only 'strike' one physical location, referred to as a 'termination'. Ī single lightning event is a 'flash', which is a complex, multistage process, some parts of which are not fully understood. The movement of aircraft through clouds can even cause lightning strikes. Lightning strikes the average commercial aircraft at least once a year, but modern engineering and design means this is rarely a problem. Most are intracloud (IC) lightning and cloud-to-cloud (CC), where discharges only occur high in the atmosphere.

About 25% of all lightning events worldwide are strikes between the atmosphere and earth-bound objects. A less common type of strike, ground-to-cloud (GC) lightning, is upward-propagating lightning initiated from a tall grounded object and reaching into the clouds. Most originate in a cumulonimbus cloud and terminate on the ground, called cloud-to-ground (CG) lightning. The presence of multiple bolts shows this is a time-exposure photographĪ lightning strike is a lightning event in which the electric discharge takes place between the atmosphere and the ground.

The metal tower acts as a colossal lightning conductor. Lightning striking the Eiffel Tower in 1902.

Plash lighting