ABSTRACT
This chapter shows that knowledge of the processes in the lightning discharge to ground, in particular the first leader stroke and first return stroke, permit a rational approach to the protection of persons and buildings against injury or damage by lightning. A lightning strike to the roof is likely to penetrate into the space below roof level, and will probably terminate on electrical wiring in the roof, with consequent damage to electrical equipment in the building, and possible fire risk. The basic principle of protection of persons against lightning injury is to reduce or prevent the risk of any portion of the lightning current passing through the person. The practical application of this principle usually takes the form of defining high-risk and low-risk situations, with a recommendation that persons move quickly to a low-risk situation if caught in a high-risk situation when nearby lightning is occurring or may soon occur.
