FAQs

Lightning is an enormous electric spark between the clouds and earth. Its power is difficult to understand but a single lightning flash may be 30 thousand amperes; that’s about 200 million volts, and will take place within less than a second.

Lightning strikes are commonly referred to as "hot" or "cold", The difference is in the amount of power dissipated and the length of time it takes for this dissipation. "Hot" bolts have a higher current and longer duration time, easily igniting combustible materials. "Cold" bolts have low current values, high voltage and short duration times, thus producing the violent shattering effect.

The Physics of Lightning

Lightning’s characteristics include current levels approaching 250 kA with the 50% average being about 25kA, temperatures to 15,000 C, and voltages in the hundreds of millions. There are some 10 cloud-to-cloud lightnings for each cloud-to-ground lightning flash. Globally, some 2,000 on-going thunderstorms generate about 50-100 lightning strikes to earth per second. Lightning is the agency that maintains the earth’s electrical balance.

The phenomenology of lightning flashes to earth, as presently understood, follows an approximate behavior: the downward leader (gas plasma channel) from a thundercloud pulses toward earth. Ground-based air terminators — such as fences, trees, blades of grass, corners of buildings, people, lightning rods, and power poles — emit varying degrees of induced electric activity. They may respond at breakdown voltage by forming upward streamers. In this intensified local field, one or more leaders likely will connect with one or more streamers. The "switch" is then closed and the current flows. Lightning flashes to ground are the result. A series of return strokes follow.

Lightning Induced Magnetism

The movement of electrical charges produces a magnetic field. The intense currents of a lightning discharge create a fleeting but very strong magnetic field. Where the lightning current path passes through rock, soil, or metal these materials can become permanently magnetized. This effect is known as lightning-induced remnant magnetism. These currents follow the least resistive path, often horizontally near the surface but sometimes vertically, where faults, ore bodies, or ground water offers a less resistive path.

Why install a Lightning Protection System?

A properly designed and installed Lightning Protection System will protect lives and buildings against a lightning strike; such a system is designed to safely carry the lightning strike to ground without damage to Life or property.

A typical system will consist of a roof network of tapes, down conductors and earth electrode locations these conductors are usually copper or aluminium as are other components of the system. These metals and their alloys are specified not only for their electrical conductivity, but also for their corrosion resistance qualities.

What is Earth grounding?

Earth grounding is a safe method of carrying a lightning strike down to earth to dissipate safety while protecting Life and property.

Copper Earth Mats or deep driven Earth electrodes with GEM. These methods can be used in order to achieve a good Earth grounding depending on the soil resistivity which can involve several factors i.e. moisture content ground make up etc. Our consultants will be able to advise you on the best option.