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<span lang="EN-US">Glass insulators, due to its diverse characteristics, were used widely around the world for high voltage transmission lines. Surfaces of the insulators are exposed to high electrical, mechanical, and thermal stresses over the period of service. Accumulation of contamination distort stresses distribution along the insulators that may lead to flashover under severe condition. In this paper, Obenaus pollution model has been adopted to propose a dynamic mathematical modelling to determine flashover critical voltage with regard to parameters such as pollution conductivity, arc length, and width of layer of contamination on the surface of glass insulator. In addition, laboratory experimental works have been carried out according to IEC60305 to validate the results from numerical approach, which indicate a good agreement.</span>

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Lightning activities are growing up rapidly with global warming. It can affect anything on the earth. All the constructed buildings need proper protection from the harmful effect of lightning. Lightning strike points on different geometrical shapes have been investigated. Lightning strike distribution of different building structure is very important to be studied. In order to analyse the maximum effect of lightning strike pattern is obtained of different air terminals installed on scaled building structures. High voltage impulse generator is used in order to get the impulse voltage. Different numbers of air terminals have been applied to all the shapes in order to see the lightning strike points. Electric field is obtained in order to see its minimum and maximum effect on the entire building structure. Interestingly the phenomenon of lightning air terminal bypasses has been proved in this paper.

Human population and power consumption keeps on growing with each year. In order to satisfy electricity demand, more electrical energy has to be supplied, resulting in higher magnetic field level radiation. In rapid urbanization country, lack of space will force civilization to be built near overhead transmission line that sparks public concern on adverse health effects due to the magnetic field radiation. A new UTHM hostel residential area was built near OTLs that shared the same concern. Thus a proper planning to conduct magnetic field level measurement was done to examine the maximum magnetic field level radiated that covered the hostel residential area. The results were far from reaching the maximum permissible magnetic field level proposed by ICNIRP. Though, the steps taken and the methods used might be suitable guidelines for others that encounter similar situations.