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This illustration is designed to demonstrate the main aspects and individual components of a structural lightning protection system.
It is not intended to represent an actual scheme conforming to a particular code of practice.
The drawing is not to scale.
Click on a link (on the right) for details.
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Conductors
The first choice faced by the designer of a structural lightning protection system is the type of conductor system to be used.
 Choose the material
required, i.e. copper or aluminium.
Choose the type
of conductor required, i.e. tape, solid circular or stranded.
Down conductor network
The down conductor system is the means of carrying the current of a lightning strike safely to the earth termination network.
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Conductor fixings
Select the correct system of fixings for each part of the conductor system. Fixings are available for a wide range of modern construction materials, eg brick, stone, plastic and metal.
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Air termination network
The air termination network is the point of connection for a lightning strike. It typically consists of a meshed conductor arrangement covering the roof of the structure.
Air Terminals
Use air terminals in the form of vertical air rods for the protection of prominent roof top features or equipment. Use strike pads to expose concealed conductors.
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Air terminal bases
Choose the correct air terminal base. This will ensure that the vertical air rods are both solidly fixed to the fabric of the structure and have a low resistance connection to the conductor network.
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Conductor jointing clamps
Select a component for the interconnection of multiple conductors or for changes of direction. Jointing clamps will ensure a low resistance, corrosion resistant connection.
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Test clamps
In order to allow periodic disconnection and testing of the earth termination network, select a test clamp to be placed within the run of each down conductor.
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Earth termination network
The means of dissipating the current to the general mass of earth.
Earth electrodes
Choose an earth electrode to suit the ground conditions in the locality of the structure. Electrodes are available in the form of rods and plates (lattice or solid).
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Earth rod clamps
Select a high copper content alloy earth rod clamp for the connection of the earthing conductor to the earth rod. In this below ground application, the clamp must ensure a good electrical contact and resist corrosion throughout the lifetime of the installation.
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Earth inspection chambers
In order to allow periodic disconnection and testing of the earth termination network, select a test clamp to be placed within the run of each down conductor.
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Bonding
Bonding is the most commonly employed method of avoiding the damaging
effects of side flashing. All continuous metalwork should be considered
for bonding. All metallic services, eg cable armoring, gas, water or
steam piping, entering the building should also be bonded as directly
as possible to the earth termination network.
Bonds to metalwork
Select the correct type of metalwork bond for the application, i.e.
a flat column face, a circular rainwater pipe or a ribbed reinforcing
bar.
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