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This paper gives an account on the historical and regional social concepts on the natural atmospheric phenomenon of the lightning phenomenon. It explores the divine concepts induced on lightning by various communities. The investigation also looks into the mythical beliefs with the objective of analysing how such conceptual aspects affect the promotion of scientific rationales of lightning safety and protection in such societies. The facts presented explain the reasons that prevent some communities from developing logical thinking and analytical skills in the field of lightning science.

Down-conductor is part of critical component in the external Lightning Protection System (LPS) as to divert the lightning current from the air termination to the earth termination system of protected structure. In this paper, numerical analysis approach incorporating the effect of copper conductor bending angle under current transient and voltage is utilized. Various angles of copper conductor will be synthesized following a simplified and generic, but meticulous, model based on the manufacturer's datasheet specification which is normally used. The fields were analyzed and the results were discussed in comparison with the MS IEC 62305-3 standard accordingly. In this case, the cross-sectional area of down-conductor was selected based on the accessible type produced by various manufacturers as proposed by the MS IEC 62305-3 standard for a critical study. This study presents the optimum angle of down-conductor with a view to develop a practical approach and to set the down-conductors in a confined area locations of a building.

Ufer grounding is an effective method for electrical earthing, especially at highly resistive soil. The main material in ufer grounding is concrete which has moisture-dependent resistivity. In previous work, mixing concrete with Bentonite was done to observe slight improvement during short term measurements. In current study, the detailed results of extended period of measurements have been presented. It was found that the improvement of the proposed mix over the standard concrete mix has increased with time. In addition, mechanical strength of the proposed mix was found to be only 10% lower than the standard mix. Therefore this suggests that the proposed mix may be applicable as the mixture for building foundation as in the case of ufer grounding.

This paper presents a characteristic of lightning electric fields. The lightning electric fields captured by two parallel plats sensor and the characterization for preliminary breakdown pulse (PBP) and first return stroke (RS) were studied. A total of 207 data were recorded and 10 data are selected and been utilized in this paper accordingly. In PBP signal data, time before return stroke, ending time and maximum peak of PBP were analyzed. The time duration between the PBP and the occurrence of RS was obtained as 0.64 ms and 2.61 ms and then compared with results from other researchers. For RS signal data, slow front time, deviation time, RS peak, time to peak, zero crossing time and 10% to 90% rise time were evaluated meticulously and the results were discussed accordingly. Moreover, the statistical correlation between electric field zero times and corresponding rise times was studied.

time an automated lightning detection system has been installed in the region. The lightning hotspots and cold spots in the country have been identified and the pattern of lightning occurrence has been compared with the thunderstorm occurrence density data collected by ground based meteorological observations. A comprehensive discussion is made on the applications of information obtained from lightning detection system in Guinea and in the region.

com Abstract- This paper presents analysis of human observations on thunder days in five regional centers in Zambia. The regions covered are specifically of interest to aviation industry. The variation pattern of monthly thunder days show that the lightning activity has well-detectable oscillatory pattern over the year. However, the pattern varies from region to region thus, as a single country Zambia experiences lightning almost throughout the year. We strongly recommend the installation of automated lightning detection system in the country to provide more accurate lightning ground flash and cloud flash density mapping. Such information will play a vital role in lightning safety and protection planning.

The experimental results that are presented in this paper show that there is a statistically significant influence of floating electrodes on rod-rod air gap breakdown under impulse current, when the floating electrode is close to either of the electrodes. The results are extrapolated to explain the influence of electrical floating metal parts in lightning side flashes, where the arcing distances are not that long. The experimental outcomes are still inconclusive with regard to direct lightning strikes where the final jump may be a gap of few hundred meters.

Split factor is a fundamental consideration when designing a distribution substation earth grid. Arbitrary choice of split factor in earth grid design process may lead to technical and economic implications resulting in underestimated or overestimated designs. In this paper, a distribution substation earth grid was designed using SESCAD and executed in MALT module of CDEGS. The energization current was varied by 100%, 75%, 50% and 25% of the short circuit current available at the secondary terminals of the upstream transformer to determine the impact on safety criteria of the earth grid. Results indicated that, the EPR for 100% fault current was higher, whereas the step and touch voltages were lower. It was also revealed that, there was no difference in step and touch voltages when energization current was set at 75%, 50% and 25%.

This paper addresses a concurrent burning issue in Uganda; the mitigation of rapidly increasing lightning hazards in the country. By analyzing various economic, technical and social factors a feasible hazard mitigation module has been proposed. The module essentially needs government intervention for providing facilities and coordination of various contributors and stakeholders for channeling expertise and possible funding. Several lightning disaster mitigation strategies have been proposed whereas practicality and limitations of applying them in Uganda are discussed in detail. Proposed modules are applicable in many countries having similar socio-economic environment

This paper presents preliminary studies on the lightning accident details in Burundi, a landlocked country in East Africa. The reported lightning incident record in 2012 and 2013 depicts that there are 52 human deaths, 94 human survivals with injuries and 40 deaths of livestock. Makamba province recorded the highest human casualties with 14 deaths and 69 injuries whereas Nyanza-Lac commune of the same province topped the list with 8 deaths and 52 injuries. The statistics do not justify the 1:10 ratio of death: injury as it is reported in USA. The statistics may be a gross underestimation as many lightning accidents are not reported due to lack of communication, especially in the rural areas. Gomes-Kadir equation estimates the death rate as 52 per year, a figure twice as high as that was observed in this study. The analysis of information for incidents over few more years reveals that seeking shelter under ungrounded metal-roofed buildings is extremely dangerous as multiple deaths may occur in the event of a lightning strike to the roof.

This is one of the first scientific investigations on lightning current and voltage distribution along Buddhist Stupa in Sri Lanka and elsewhere. Such distribution provide vital information on lightning safety concerns of people and objects outside the structure as the building is totally sealed. The metal casket of which the block of quartz is installed at the pinnacle of the Stupa, may act as the point of interception with lightning stepped leader. Large hemi-spherically symmetric outer structure of the Stupa causes uniform distribution of current over its surface. Such distribution yields very low current density thus possibilities of side flashing or localized heating are minimized. Structure of the Stupa was analyzed as a collection of lumped circuit elements using MatLab and SimuLink software to show that there will be no dangerous potentials developed within possible arcing range to the surrounding, in the application of impulse current. Thinly distributed current, driven into the deeply laid foundation of the structure, prevents development of significant step potentials in the vicinity that could pose danger to the devotees.

Information by the media in advance of severe weather occurrences can prepare the public to respond properly during an emergency situation. At the same time, the media should work as a channel to communicate and promote proper public response to severe weather threats. The objective of this study is to examine the position of the media as a tool of communication and education on severe weather in Malaysia. Results indicate that the present role of the media in Malaysia is still insufficient in communicating and educating the public on severe weather.

The objective of this study was to examine the influence of socio-demographic factors on severe weather concern, knowledge and preparedness among urban and semi-urban residents of Malaysia. Results indicated that a broad-based education approach could be used to enhance community preparedness to severe weather risks as age, education level, gender and ethnicity did not influence all the variables of the study.

The minimum separation between a human body and 10 m high objects struck by lightning, to avoid side flashes, has been studied. Objects with different materials and cross sectional areas have been considered. The parameters of lightning current waveform used in this paper are those pertinent to negative subsequent strokes given in IEC 62305-1 (2010). Since the minimum separation between a human being and an object struck by lightning is related to human safety, the worst case scenarios are considered. The distance between a two meter tall human being and the object struck by lightning is varied and the distribution of electric field around the object was calculated. Consequently, we computed the minimum separation between the human body and the lightning struck object with a range of values of resistivity and cross sectional area so that the probability of side flashing during a lightning strike have been discussed.