Screening and a correct selection and coordination of Surge Protective Devices avoids important losses.
Lightning is a phenomenon that involves a huge energy. Even if the structure is correctly protected against direct strike, lightning electromagnetic pulse (LEMP) can cause failures in electrical and electronic systems. Connected wiring may transmit conducted and inducted surges to the equipment. Besides, strikes to structures, to the nearby ground or even lightning electromagnetic field may affect directly the equipment.
The standard IEC 62305-4 describes these sources of damage and indicates, with detailed calculations, how to minimize these effects with cost-effective measures. Some of these measures are the screening of some zones of the structure or the connecting wires. Also, the standard gives the criteria for the selection and especially for the correct coordination of surge protective devices in order to optimize security measures that avoid failures of the equipment.