Lightning phenomenon

Devastating effects of lightning

Without any appropriate protection, the lightning current propagation can produce several effects. That is the reason why, it is necessary to arrange protection according to basic rules, paying attention especially to earthing systems and interconnections with conductive elements, and to the down conductors and electrical equipment in the installation. 

LUMINous effects

The ionization of the air produced by the lightning current provokes numerous luminous particles, or “photons”. It can create an image on the observer’s retina which may leave him dazzled for several seconds before regaining his sight.

acoustics EFFEcTS 

The current of lightning is at the origin of enormous electro dynamic forces, which result in a strong rise, in the pressure of the air (2 to 3 atmospheres) in the outfall channel. The shock wave created or “thunder” can be heard at many kilometres from the impact point, like rumbling or crackling sounds, according to spectral distribution and position of the observer.

EFFEcTS DUe to electrical arcs

The resistivity of the soil and earthing systems provoke a sudden rise in the potential of the installation, when a lightning current passes through it. Differences in potential can appear on various metal parts connected incorrectly to the earthing system creating excitation, electrical arcs and destruction of electrical or electronic equipment.


Close to the path of lightning current, appears a strong magnetic field creating voltages and induction current on all conducting elements situated in its sudden action field. The mechanical forces induced can provoke deformation, twisting, and destruction, …


As the path of the lightning current can provoke death, the dispersion of lightning current in heterogeneous soils can create potential differences dangerous to all live animals and people (pace voltage). These can provoke burns or heart attacks and respiratory problems.

THERMal effects

Thermal effects or “Joule effect” can create at the impact point the melting of the materials and even their destruction by explosion when it presents a high humidity rate or causes fires to start.


eLECTROCHeMIcal effects

These effects are caused by the chemical decomposition of the materials by electrolytic reactions. Although very negligible and without effect compared to stray currents in the soil, it appears mainly at the earthing systems level.

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