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Background COVID-19 has drastically dampened human activities since early 2020. Studies have shown that this has resulted in changes in air temperature and humidity. Since lightning activities are dependent on air temperature and humidity, this study is conducted to evaluate the correlation between the intensity of lightning activities with the atmospheric changes, and investigates the changes, in lightning activities due to atmospheric changes during the COVID-19 pandemic. Methods The hypothesis was tested through a t-test and Pearson’s correlation study. The variation trend of lightning strikes count (LSC) in Europe and Oceania during the five months COVID-19 lockdown period (March – July) compared to the same period in the previous five years from 2015 to 2019 is investigated. Results Statistical analysis shows the LSC in Europe and Oceania during the lockdown period dropped significantly by more than 50% and 44% respectively compared to the same period in previous five years. Furthermore, LSC was found to be positively correlated with air temperature and relative humidity in Europe. However, in Oceania, LSC seems to be only positively correlated with air temperature but negatively correlated with relative humidity. Conclusions This study seems to suggest that lightning activities have significantly changed during this pandemic due to reduction in human activities.

Lightning Induced Overvoltages (LIOVs) on short, floating Medium Voltage (MV) lines can be either calculated or measured using existing methods. These results are then normalized and extrapolated to estimate the lightning performance of long operational MV lines. Existing models can become complicated and some crucial input data may not be available when the line is long, has line equipment connected to it and is energized. Accurate LIOV measurements on an operational MV line are not viable due to the large number of measurement instruments required and the accompanied logistics. This paper describes a new measurement method to distinguish between nearby lightning and direct lightning strikes to the line for lightning performance investigations. It also indicates whether the LIOV exceeded the line Basic Insulation Level (BIL).

This paper presents the design, simulation and analysis of the distribution of lightning current and transient voltage in a 25 kV AC railway traction system. Consequently, the lightning protection system that may mitigate the adverse effects due to possible lightning strikes has been designed. The Mpumalanga- Richards Bay Coal line in South Africa has been considered for the analysis. The railway system is modelled, consisting of a mast, an insulator applying a back flashover control mechanism, overhead catenary wires, a pantograph, an AC locomotive and the rails. The main component of protection is the surge arrester that is designed using the PincetiGiannetoni model. The surge arrester is rated at 30 kV, with a nominal discharge current of 10 kA. The complete system is modelled and simulated in PSCAD software. The simulations are performed to detect the transient response of critical components of the system when lightning current is injected at locations of exposure, namely; the mast, catenary wires and the pantograph, in the absence and presence of surge arresters. The results show a significant decrease in the peak current and voltage of the selected components when surge arresters are connected.

Being a spectacular atmospheric phenomenon, lightning could induce significant interest in the human mind since the beginning of history. Most often the public perceptions of many communities about lightning were marked by divinity, power, fear and punishment. The belief systems extend up to the present time, despite the development of modern science and technology. In the last two centuries, the scientific understanding of the thunderstorm and lightning phenomena gradually improved and at present we have a significant awareness of the nature of lightning, injury mechanisms and lightning-related medicine. The modern safety guidelines and safety modules for communities in lightning-dense geographical areas are based on proven scientific facts. In several developed countries, a marked decrease in the number of lightning casualties could be observed during the past century, due to the continuous safety awareness programs. However, lightning safety modules which are highly successful in one part of the world may not be that successful in another part of the world.

Introduction: Malaysia is one of the countries with the highest lightning flash density globally. While sufficiency of lightning protection system is crucial to ensure human safety against lightning strikes, the public awareness towards lightning safety is also equally important in Malaysia. Hence, this study was conducted to understand the current lightning safety awareness level of the Malaysian population. Methods: An online questionnaire survey which consists of 22 scientific statements of lightning was first developed in Malay and English. The questionnaire allows the respondent to also check their own score upon completion of the questionnaire. It was then distributed to the public for data collection. The sample size comprised of both genders, all layers of society from various educational level and social background. Results: Overall, the awareness on lightning safety amongst Malaysian is at moderate level with an average score of slightly above 50%. Urbanites scored marginally better than their rural counterparts. One’s education level does not dictate their awareness level of lightning safety. Discussion: In conclusion, the public in Malaysia needs to be better educated on lightning safety. Similar studies should be replicated in other countries experiencing similar levels of lightning activity to better understand the public’s perception on lightning.

Outcomes of a comprehensive survey on the public beliefs in Malaysia with regard to the nature of lightning and lightning safety have been presented. A questionnaire survey is done among 100 respondents, comprised of an equal number of participants from each gender. Despite the sample is biased towards educated layers of the society, the concepts of a sizable fraction of the sample are in contradiction with accepted scientific norms. Only 54% of the sample indicated disagreement with incorrect statements in the questionnaire. The percentage that agreed with correct statements is slightly below 50%. Such information plays a vital role in developing lightning safety guidelines for a given region. It is advisable to plan the safety modules in line with these beliefs, at least at the initial stage, rather than having myth-busting type approaches from the right beginning.

This study briefly canvasses lightning fatalities in Malaysia. Acquiring lightning fatality statics are a challenge as mandatory reporting of such events is seldom required, and as such, many lightning incidences were unreported. For that reason, numerous cases were undocumented in the official records. However, for injury prevention efforts and calling a government's attention to these as a severe problem, information on numbers, exposed locations and their backgrounds are essential to determine vulnerable areas. A theoretical approach using Gomes-Kadir equation was also tested to estimate annual lightning deaths in each state of Malaysia using lightning density and sociological factors and the results compared against known fatality data.

While in-depth studies of lightning deaths can be found in the literature, rarely do such investigations they utilize a multidisciplinary approach, analysing both the medical and electrical aspects of a case. Even more rare, is to find such studies on cases from the developing world such as Africa and South-East Asia - particularly in tropical countries with very high lightning exposure. This paper details the forensic investigation of two lightning deaths that took place during a weekend in February 2020, in South Africa. One event was eye witnessed and the other was not (Case A and B). The investigation involves multidisciplinary forensic examination including case histories, site analysis (including soil resistivity measurements), medical autopsies, lightning location system data analysis and voltage gradient estimations. In both cases, lightning is determined to be the cause of death. In Case A, we confirm that the responsible flash must have attached within close proximity to the deceased, if not a direct strike and in Case B we confirm direct strike as the most probable mechanism of death. The importance of clothing examination in the forensic studies of lightning victims is noted along with a discussion of the lightning safety issues at play, and recommendations for avoiding such incidents in developing world countries.

Lightning strike causes large transient current injection into hybrid systems at the point of contact. The generated transient overvoltage due to lightning current is a high concern on various expensive electrical equipment of the hybrid system and is meant to be studied in depth to reduce damages caused by this overvoltage. Analysis of lightning transient effects on a hybrid PV-wind system has been carried out in this study. The complete model of the system has been simulated by PSCAD /EMTDC software. The system consists of 2 MW PV farm, 2.1 MW wind farm, energy storage system and load. The entire system is integrated with the utility grid. Lightning current is generated by Heidler function with the help of same software. In this work, two points are selected from hybrid system to inject lightning current. The first point is the DC side of the PV modules whereas the other is the wind turbine tower. In the second case, the partial lightning current is assumed to be injected into the electrical part in the form of arcing. Transient overvoltage has been observed at different locations of the hybrid system by injecting lightning currents; the simulation results are obtained for 50% waveform of negative first stroke and negative subsequent stroke.

This is one of the first studies on lightning incidents that take place in the neighbourhood of Lake Victoria, the largest tropical lake in the world that borders Uganda, Tanzania and Kenya. Lightning accident statistics in the region have been documented segment wise. The number of lightning occurrences in the north-western shore and that in the north-eastern shore were compared. The region has a distinctly recognizable season with high lightning accident density which runs from May to November and low lightning accident period from December to April. August peaks in lightning incidents. Lightning-related incidents are very much prevalent during the period between May and August due to the dominant south easterlies. The study reveals that the north-western part has slightly higher lightning accidents than the north-eastern part. North-eastern part records relatively high number of lightning accidents in the morning hours whereas the north-western sector experiences the same in the afternoon hours. Many features of lightning accidents and their locations have features that are in agreement with the same observed in other parts of East Africa. Following the statistics collected and incidents observed, suitable safety measures have been recommended for the communities that reside in the shores and nearby areas of Lake Victoria.

The essence of grounding in power systems is very essential. This paper presents the performance and characteristic of backfill material such as bentonite and conductive cement. The backfill materials pay a pivotal role in controlling ground impedance of the soil. Protective devices are normally used to divert an excessive current during lightning strikes through earth rode to avoid damages to the equipment. Swaziland has been experiencing a lot of power failures due to lightning especially during rainy season. Most of their transformers has been lost because of this problem. Most of Swaziland network is overhead which is exposed to lightning. It is thus important to design an effect earthing system that will be able to protect the equipment during fault conditions. In this study, it has been found that the behaviour of backfill material depends on the voltage applied. It was also found that the time to breakdown in comparison between bentonite and conductive cement. This paper highlights some of the aspects need to take into consideration for grounding for a country like Swaziland.

How is lightning protection ranked in the field of safety science? What is the general perception of the public with regard to the risk of receiving a lightning strike to their building? How do business entities manipulate the psyche of the public in upsizing financial gains? What is the true risk of public adopting lightning protection techniques that have not been included in major international standards? Is the research presented so far in condemning the lightning protection systems rejected by the scientific community, well-conducted? Is tabooing of some lightning protection technologies a productive strategy in driving the public to adopt protection systems recommended by international (IEC) standards? This paper makes comprehensive attempts to answer these questions.

When a tower is struck by lightning, an induced voltage can generate in conducting objects within its vicinity. This phenomenon is due to the interaction between the electromagnetic field of the lightning with the object. The magnetic field is part of this field. Previous studies have shown that the magnetic field is affected by ground reflection coefficient factors that are usually taken as constants. However, the ground reflection coefficient factors have correlation with tower and ground impedance whereby the ground impedance can be determined based on soil resistivity and grounding system. This paper investigates the effect of soil resistivity on the value of magnetic field for a case of lightning strike on tall structures. Lightning current has been modelled accordingly and a set of equations is proposed to evaluate the magnetic field. Also, the effects of soil resistivity on the value of ground reflection coefficient factor consequently of the magnetic peak have been investigated. The results indicate that the magnetic field changes substantially with a variation of the soil resistivity. The magnetic field peak also has a strong correlation with the changes of soil resistivity as well as the fast front time of the channel base current. The outcome of the result of this paper will be beneficial to utility companies in determining the appropriate level of lightning protection since the magnetic field will be a result of induced voltage when have interaction with power lines.

Fulgurites are natural tubes of glass formed by the fusion of silica sand or rock from a lightning strike. The fulgurites have been produced artificially in HV conditions in the past. Recent studies have found that fulguritic structures can be formed in some other materials, such as bentonite and cement, as well. These fulgurites can change the overall physical and electrical properties of the original materials. Thus, formation of fulgurites can modify the performance of electrical earthing systems, both ordinary and those improvised with backfill materials. This study investigates the fulgurite formation under alternating, direct and impulse current application. Bentonite and sand were tested under high voltage conditions. The type of fulgurites and their effects on electrical earthing systems were studied by analyzing the resistivity and permittivity of original materials and fulgurites. It has been found that fulgurites formation has a severe effect on the earth resistance of grounding systems.

This paper validates the performance of low-cost lightning protection systems for small structures proposed by researchers in the past. Such structures have an acute demand in the countries with very high lightning ground flash density, yet the affordability of the mass public is quite limited due to the struggling economies of the countries. The protection systems for small housing structure, and a standalone protection structure for one or few people have been investigated by implementing the structures in HFSS/ANSYS software which employs finite element method. By applying current waveforms to represent first negative return stroke, subsequent negative return stroke and positive return stroke, the electric field and potential gradient of the entire space and the current density and the thermal profile of the protective structure have been computed. The objectives were to find whether the voltage distribution in the wake of a lightning strike could initiate side flashes, generate touch potential and step potentials that exceed dangerous levels, drive current densities due to which the structure collapse under thermal effects. It has been found that the proposed protective structures could suppress side flashes and harmful effects due to step potential while the structure will be able to withstand the heat generated. However, the touch potential could still be beyond the human injury thresholds, thus a minimum separation from the lightning current passage should be advised to the occupants.

This paper addresses a concurrent multidisciplinary problem: animal safety against lightning hazards. In regions where lightning is prevalent, either seasonally or throughout the year, a considerable number of wild, captive and tame animals are injured due to lightning generated effects. The paper discusses all possible injury mechanisms, focusing mainly on animals with commercial value. A large number of cases from several countries have been analyzed. Economically and practically viable engineering solutions are proposed to address the issues related to the lightning threats discussed.

This paper provides comprehensive analysis on the lightning protection scenarios in 48 communication and broadcasting towers situated in similar isokeraunic contours in Sri Lanka at 79°–81° East and 5°–10° North. The investigation has been conducted to study the hazardous environment created on the tower and in the neighbourhood in the event of a lightning strike to the tower. The results show that a direct strike to an antenna structure in a metallic tower is rare irrespective of the presence of an air-termination or a down conductor. However, side flashing or arcing to antenna structures is highly possible once the air-termination and/or down conductor is installed and attempts are made to insulate the system from the tower. The outcome also shows that equipotential bonding of the grounding system, a distributed grounding network including a ring conductor and a suitable system of surge protective devices play a much vital role in lightning protection of equipment and safety of people compared to the effects of simply achieving a low grounding resistance. However, in the absence of such integrated, distributed and equipotentialized grounding system, a high value of ground resistance will sharply increase the possibility of accidents and damage. Considering the observations of the investigations into account we have designed a concrete embedded grounding system for tower sites at problematic locations. Finally, the scenarios for safety management at telecommunication tower sites have been discussed.

This study investigates possible lightning threats to naval crafts, especially those sailing in the shallow waters of tropical oceans where thunderstorms prevail throughout the year and Far-East Asian region where dangerous positive lightning is a signiflcant characteristic in winter thunderstorms. It is empathized that sea water acts as nearly a perfect conductor thus lightning electromagnetic transients propagate over the sea with almost zero attenuation of amplitude and high frequency components intact. The ratio between the peak electric flelds at 5km from the lightning channel, after flelds propagate over dry soil and over sea water is 0.75. The ratio between the peak electric fleld derivatives under the same conditions is 0.1. Such small ratios are observed in the magnetic flelds and their time derivatives as well. Apart from the conductivity, the topological irregularities of the plane over which propagation takes place also contribute to further attenuation of flelds and their time derivatives. This makes marine naval systems more vulnerable to lightning induced efiects than their ground-based counterparts. The paper discusses in detail the lapses of existing naval standards in the defense of electrical and electronic systems against both direct lightning currents and induced efiects of nearby lightning. Consequently we propose the development of a dedicated standard for the lightning protection of naval systems, with the inclusion of several signiflcant recommendations specifled in this paper.

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.

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.

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.

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.

Lightning current is an important parameter that has to be considered. The different behaviour of lightning current depends on the way the lightning strikes either as a direct or indirect lightning strike. In this paper the modelling of the current as a result of a direct strike of lightning on a tall structure is considered. A few of up-to-date on current models, current functions, reflection factors, the return stroke velocity (RSV), the general equation representation of this case are reviewed. Also, through MATLAB software, the results of a case study are generated. The results show a good agreement with the measured values. In addition, the behaviour of the lightning current is evaluated at different heights of the lightning channel with respect to the top and bottom of a tall structure. Also, the lightning current at the top and bottom of the tall structure are observed for different values of the reflection factor. The results show that the peak of the lightning current along different heights of the channel with respect to the top and bottom of a tall structure decreases with increasing height of the channel. Also there is a time delay during the initial time period. Furthermore, the lightning current at the bottom of a tall structure has a high value of peak current and has an attenuation wave shape of current that compares with the lightning current at the top of the tall structure. As a result, this paper may provide benefit in evaluating the electromagnetic (EM) field since the behaviour of the lightning current on a tall structure is known.

Metallic part would play an influential role in the case of probability of lightning strikes. An experimental study has been done to find out the effect of the presence of floating electrode on the body during thunderstorm. Although, it is clear that a small metal part on the body or in vicinity does not have effect during direct strike, the effects has been examined only in the case of side flashing. SPSS has been used to check the statistical significance of the probability. According to the result, floating electrode may shorten the gap distance of the struck point and a human body thus increasing the probability of lightning side flashing. The test has been done covered floating electrode (insulated) as well. Thus, it is recommended to either remove or isolate the metal parts during thunderstorm.

This paper presents analysis of various potential lightning risk scenarios, especially in less developed communities. We identify that there is no uniform safety promotion module that may be applicable to all communities with success. Hence we develop a hierarchy of hazard control mechanism that may be applicable to any given community with uniform professional or social practices. The hierarchy of control ladder has been integrated with the responsibility distribution network that runs from government level to the potential victim. The mechanism could be adopted by designers of lightning safety promotional programs in many parts of the world by appropriately determining the tools of implementation at various societal and professional levels. It is expected to minimize deaths and injuries as well as property damage due to lightning in vulnerable parts of the world.

Lightning protection of oil storage tanks has becomes a controversial subject, due to conflicting protection criteria. One such is the sense of using self-protection criteria, relying on the strict fulfillment of the operational conditions, material thickness and reliable bonding; the other refers to the necessity of standalone lightning protection system (LPS) where air terminals are installed in order to avoid any interception between the lightning stepped leader and the tank body that could cause hot spots and excessive temperature rise. Each method has its own advantages and drawbacks. In this paper these criteria are analyzed with critical view in order to make appropriate decisions in selecting the most suitable method of protection for a given situation.

This paper addresses the lightning safety environment in Uganda that requires urgent and serious attention of the international expert community. We present recent statistics of reported lightning incidents in Uganda which show that the number of injuries and deaths are overwhelmingly high during year 2011 thus the situation can be declared critical. During the five-year period from January 2007 to December 2011, there were 91 reported lightning accidents which accounted for a total number of 150 deaths and 584 cases of personal injuries to which the victims did not succumb. Out of 150 deaths 95 reported in 2011. The actual number in each case may be much higher as many deaths and injuries go unnoticed due to lack of communication between rural communities and government authorities or media sources. The detailed analysis of several incidents reveals that injuries and deaths are basically due to both lack of awareness and absence of proper protection and safety schemes. The decisive factors of the ill-effects of incidents are time of the day, month of the year, part of the country, location of the incident etc. Most of the accidents have occurred either in the afternoon or in the evening. A spread of incidents can be seen throughout the six month period from June to November with June as the month of highest reported deaths. The highest number of incidents has been reported in the Northern Province of the country. Interestingly, the highest number of incidents, deaths and injuries has occurred while the victims were inside permanent structures. After analyzing these incidents a stepwise procedure is proposed to curb such incidents in the future.

Sri Lanka, a tropical island in the Indian Ocean, experiences relatively high density of lightning. The island has a record of lightning research and lightning education programs that dates back to several decades. Lightning research in the country has a number of measurable outcomes; however, there are no indicators to evaluate the success rate of awareness programs. This paper summarizes the activities pertinent to lightning research and education carried out in the country so far and analysis of information gathered during the recent times on public opinion on various critical safety and protection issues. Consequently, based on the outcome of analysis new modalities are proposed for countries with similar lightning density and social structure to launch lightning education programs with success.

This paper discusses various practical difficulties of implementing internationally and nationally recognized lightning protection standards on small shelters. In aiming to minimize human injuries and deaths due to lightning related accidents for people who take shelter in unprotected structures during thunderstorms, this study proposes out-of-the-box solutions that may save many lives in societies that cannot afford packages of total solution. However, the proposed protection schemes can be applied even in developed countries or wealthy societies where strategic problems such as remoteness of the sites of concern and practical solutions beyond the peripherals of standardized recommendations are demanded. It should be noted that these are last resort solutions rather than replacement for recommendations in international standards.

Lightning is a major cause of weather related mortality around the world. In the United States, lightning typically kills more people in a year than any other storm disaster except floods. Due to persistent lightning safety efforts and an annual national Lightning Safety Awareness Week campaign, US lightning deaths have decreased to an average of about 50 per year in the past decade. Good statistics about death and injuries around the world are just beginning to be collected. This paper presents an update and overview of the global statistics and trends on lightning fatalities which include the gender, activity, time of event and number of casualties. In addition, meteorological info will also be considered in relation to the lightning activity and fatalities.

In this paper we show that the scale of damage in buildings with steel reinforcement, due to direct lightning strikes, is insignificantly small compared to the lightning effects on buildings and structures with no such steel reinforcement. The observed small-scale damages are also confined only to the point of strike. A large number of such cases have been observed in Sri Lanka and Malaysia. The fact that almost all these damaged structures, observed in this study, have a steel reinforcement structure, but not verified to be in compliance with the specifications in IEC 62305-3 (2006) for it to act as down conducting system, prompted us to re-think regarding the specifications. Such specifications are difficult to be achieved in practice and also not applicable to buildings that have been already constructed. The recommendations prevents the engineers from using the steel reinforcement as the down conductor in many cases; a fact that leads to either non-installation of LP systems or adopting non-conventional systems which are convenient to be installed. In both cases, a noteworthy advantage that could have obtained by using the steel reinforcement is lost. Use of the steel reinforcement as the down conducting system, which is integrated to a properly designed air-termination system could have prevented even the small-scale damage occurred at the attachment point. Hence, we strongly recommend revising the relevant recommendations in the standards so that a mass public will be benefited. In the absence of such relaxation of the existing guidelines the manufacturers and proponents of nonconventional lightning protection systems enjoy an undue advantage in promoting their technology.