For many decades, the principals and senior management of LPI have been providing specialist lightning protection advice to customers in some of the most. Visit our website and learn more about AS/NZS standards. You may require this Standard if you are an electricity network operator or electrical contractor and intend to: design; construct; commission.
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The risk calculations implemented represent a simplification of the approach outlined in initial work by IEC Committee TC 81 with the number of variables and options requiring selection reduced to a minimum based on assumptions for general conditions in Australia nzz New Zealand.
AS / NZS Lightning Protection – AG – Australian Business Licence and Information Service
Successive calculations can be performed to observe the effects of various protection measures. Please address your comments to the Chief Executive nss either Standards Australia or Standards New Zealand at the address shown on the back cover. Suitable application of surge protection requires correct installation, earthing and coordination of aa rated SPDs. Between six and ten people are killed by lightning in Australia each year. Where headsets are used for a large percentage of the time, or where operators may be unaware of local lightning storms, the risk of injury from lightning can be dramatically reduced by the use of wireless headsets.
Unless it has been specified that lightning protection must be provided, the first decision to make is whether the lightning protection is needed. Do ass lie on the ground as this could cause dangerous voltage to develop across the body by earth currents generated by a nearby strike.
No telephone related deaths have been reported in Australia. In general, it is not economically possible to provide total protection against all the possible damaging effects of lightning, but the recommendations in this Standard will reduce the probability of damage to a calculated acceptable level, and will minimize any lightning damage that does occur.
Hence, lightning strikes to the ground anywhere on this metallic network may cause shocks elsewhere.
AS / NZS Lightning Protection
In such a case the tolerable risk, R a for loss of sa value would be set at 10 The total risk, R, is made up of the sum of a number of risk components associated with the four possible sources nzx damage according to the point of strike as listed below: Do not stand on or under bridges or other elevated structures.
Where danger from other causes such as toxicity, asphyxiation, and radioactivity may arise this is specifically mentioned. Hzs LPS for the structure comprises an air terminal network to intercept the lightning strike, a downconductor system to conduct the discharge current safely to earth and an earth termination network to dissipate the current into the earth. Observance of these rules will ensure that appropriate interception protection is provided by air terminals for the parts of structures most likely to be damaged by direct lightning strikes, that the conduction of the lightning current by the downconductors is adequate and that it is ns into the earth by the earth terminations.
The term refers exclusively to the danger arising from ignition. Do not use personal computers and other electronic and electrical equipment, and avoid contacts with sinks, ax, refrigerators, metallic pipes and other large metallic objects in the house. The selection of the most suitable protection measures shall be made by the designer according to the contribution of each risk component to the total risk, and according to the technical and economic aspects of the different protection measures available.
It should also be noted that the usual neurological criteria for death xs be unreliable in this situation. The remaining steps are referred to in the design rules and their application is referred to in subsequent sections. This evaluation considers mechanical damage of the structure and contents, damage and failure of equipment, potential differences causing deaths of people and nzw from step and touch voltages, and fire damage that may result from the lightning discharge.
Conductive electrical service lines include electricity supply service lines underground or overhead and telecommunications service lines.
The TP for incoming services includes the use of isolation devices, the shielding of cables 11768 the nxs and coordination of SPDs. Public money would normally jzs spent to try to eliminate or reduce to a level as low as reasonably practical the causes of risks greater than 10—4 per year i.
Indoor and outdoor pools are treated the same with regard to lightning dangers. A receding local thunderstorm is no longer a threat when more than 30 min have elapsed after the last thunder is heard.
These may include— a measures limiting step and touch voltages; b measures limiting fire propagation; c measures to mitigate the effects of lightning-induced overvoltages e.
Other work sheets showing the calculated values of all of the individual risk components for each type of risk are also accessible if a more in depth analysis is required.
Some special hazard factors also need to be considered. Section 3 provides advice on the protection of persons from lightning, mainly relating to the behaviour of persons when not inside substantial buildings.
These rules are the first step in the process of the design of a complete LPS. For each protection level, a set of maximum sizing criteria and minimum interception criteria lightning current parameters is fixed, together with the corresponding rolling sphere radius. Persons within a substantial structure are normally protected from direct strikes, but may be exposed to a hazard from conductive electrical services entering the structure or from conductive objects within the structure that may attain different potentials.
Please consult the Contact Officer for more information and to ascertain the level of compliance if any that may be required. Before any decision is made not to install lightning protection to a structure, consideration should be given to the factors outlined in other sections of this Standard.
It may be composed of one or more simple probabilities of damage.
AS1768-2007 – Lightning Protection
In the case of pipelines, with no metallic gasket on flanges, conveying explosive fluid. Extra protection is applied at the zone boundary to minimize the risk of damage to equipment inside the zone. Similarly, if it were considered acceptable for such a loss to occur, on average, once every years, Ra for loss az economic value would be set at A person touching or close to an object struck by lightning may be affected by a side-flash, or receive a shock due to step, touch or 1786 potentials.