The subject of lightning, or how to mitigate (reduce) its effects on your equipment, is not immune to the enormous amount of mis-information available on the web today. Thanks largely to the myths surrounding grounding and lightning safety, many well-meaning amateurs are driven by misguided beliefs, often leading them to apply questionable practices or equipment methodology that is anywhere from useless to dangerous. The goal here is to educate you and help de-bunk the prevalent myths surrounding this oft-misunderstood topic by providing you with good, useful knowledge in plain English.

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Abstract (about this article, in a nutshell) Lightning is a very powerful natural phenomenon that can be quite destructive. Unlike AC or DC, it's a transient discharge of static electrical charges. Many myths surround the nature of lightning, possibly due to its difficulty to control and the misunderstanding of transient electrical event behavior. A static electrical discharge can manifest itself anywhere from a small, harmless drain of charge through a wrist strap to a huge lightning bolt from miles away. When a relatively small static discharge occurs, it's not often acknowledged as being related to the larger one because of the differences in appearance, sound, and other effects on objects through which the discharge takes place. While not always possible, a person can take measures to reduce the destructive effects of lightning on equipment, structures, and people. Lightning safety is a key concern for commercial antenna installers, electricians, amateurs, and insurance companies, who take this force quite seriously.

Contents

What exactly is lightning? Atmospheric static discharge Lightning behavior Where and when will lightning strike? What is a direct lightning strike? How to minimize the adverse effects of lightning Unplug or leave plugged in? Will my outdoor antenna attract lightning? Popular lightning myths Protecting yourself from lightning Summary References About Noji

What exactly is lightning? A static electrical discharge is a movement of static electrical charges (such as free electrons) from a source of one electrical potential to that of a lower electrical potential. It can be the discharge of numerous electrical charges or a few. Lightning is a label placed on the sudden and massive static discharge that's typically accompanied by a blinding flash and deafening thunder, and often occurs in multiple very short bursts through the same path. Lightning is neither AC nor DC, and is better known as a set of transient electrical pulses; that is, it's a lot of electricity that flows in bunches and in a very short amount of time. Free electrons collect on stuff like a balloon, your carpet, and your hair, because the atoms to which these electrons "stick" contain conduction bands that do not easily pass electrons along to the next atom, so we call them insulators. Materials such as copper wire, an antenna, and your metal tooth filling are typically made of materials whose atoms have conduction bands that easily pass electrons on to the next atom, so we call them conductors. Static charges stick to everything that easily ionizes, including insulators, and when they come in contact with conductors, they're absorbed into their conduction bands, and are carried along as current in an electrical path. Lightning starts out as static charges that get swept into the current when a bunch of them come into contact with a conductor. Sometimes, that "conductor" is nothing more than air that's been ionized by the electric field created from the potential difference between objects of accumulated charge. When that huge accumulation of charge moves through the conductor in an attempt to equalize the potential difference, that movement often carries with it an enormous amount of energy. And when the movement exceeds the energy-carrying capacity of the conductor, the overload often results in a very visible, incandescent display of that energy, whether that's in a undersized copper wire or in the ionized air. The average energy E dissipated by a lightning discharge is the result of its average power P output for the duration, such that E = P x t. The power of lightning arises from a huge amount of current transmitted through a dissipative (resistive) medium, or P = I2R. Thus, the higher the resistance, the greater the resulting power and the larger the energy delivery. The energy released by such a discharge is manifest by a very large spectrum of electromagnetic radiation, which includes RFI (radio-frequency interference, or the "static" you hear on the radio), visible light (the intense flash), and high-intensity infrared radiation, which causes nearby stuff (wood, skin, air, etc.) to heat up rapidly. At first glance, it might be reasoned that greater resistance should actually reduce the quantity of power delivered, according to P = V2/R. But the reality is that, once the electric field has established the path, the system tends to act more like a constant current source than a constant voltage source because that reservoir of charge tends to empty very quickly (I = q/t) due to the electric field gradient. Therefore, since air exhibits greater resistance than, say, steel, a lightning arc is more likely to be visible if it's traveling through the air than through the steel. By the way, when lightning passes through resistive media, the amount of heat generated can reach over 30,000 K, about five times the solar surface temperature. And speaking of arc, if a conductor, like a wire, came sufficiently close (less than ~3000 V/mm @STP) to another with a lower electric potential, the air between the two can ionize, forming a conductive path and a subsequent arc. The arc is typically a spark-sounding flash, nothing more than a miniature version of lightning. This semi-oversimplification is an attempt to bring the phenomenon of lightning down a little closer to human experience. Lightning is technically more of a spark than an arc; nevertheless, the brightly lit pathway is classified as a type of plasma. Thunder, another lightning by-product, is the rapid expansion and contraction of heated air, producing a momentary pressure differential resulting in the high-energy acoustic shock waves that tend to freighten both us and our pets. And because lightning storms are typically accompanied by thunder, we often refer to them as thunderstorms. In fact, thunder cannot exist without lightning, because it's created by the unique atmospheric assault that can only originate with a lightning event. Although rare, thunder has been known to rupture eardrums and topple chimneys.

Atmospheric static discharge Long before lightning is formed, huge collections of free static electric charges gather on insulating yet regionally ionized clouds. Where these "free" electrical charges originate is a subject of controversy, because they appear to be generated by either proximity (two things coming really close to each other) or by friction (things rubbing against each other). The triboelectric effect is a name given to explain the generation of static electricity when two materials transfer charge by means of friction. To date, there is no consensus on the validity of triboelectricity as a means of static generation by rubbing because in most cases contact proximity can demonstrate the same result, as is evidenced with a Van de Graaff generator. In other words, practical human experience does seem to demonstrate the effect, but science as yet is unable to satisfactorily validate it as fact. It's been observed that triboelectric collisions of hail particles are often responsible for the massive charge in clouds, further "clouding" the issue. Static electrical charges can accumulate in clouds and other non-conductive objects, then discharge through a conductor. But if that conductor is air that's been ionized by hail and a big electric field, it often needs some help to complete the conduction path for the discharge to take place. Because the air does not possess uniform impedance, its ionization takes place in small sections connected by occasional higher-impedance gaps. Each connective section average around 150 feet long and is called a stepped leader. While stepped leaders start from a cloud and snake their way to the ground, several sets of leaders known as upward streamers start from the ground because of the polar nature of the electric field. Eventually, one branch of leaders from the cloud makes contact with a branch of one of the streamers rising from the ground (called the attachment process), and when it does, the static charges now have a path, and electrical current begins to flow. The result is a blinding flash known as the return stroke because it tends to visibly move from ground to cloud. Most lightning occur between clouds, known as intracloud or a cloud-to-cloud event. While lightning concerns exist due to intracloud events for aircraft and spacecraft, protection is most relevant to lightning that occurs between the clouds and something on the Earth, known as a cloud-to-ground event. Lightning event types other than these two exist, but are not nearly as common or as dangerous. Lightning can also travel from ground-to-cloud, but that's less common and doesn't add to our protection discussion. Although by no means conclusive, for convenience let's refer to the cloud as the source of the electrical energy that discharges as lightning. As mentioned, other static sources, such as aircraft, the Earth, or a body of water, can provide the reservoir of charge necessary for a lightning event, but the big arcs that require protection attention in our discussion tend to originate in the clouds. Extreme lightning, known as a megaflash is rare, but does occur under the most optimum circumstances. The largest megaflash ever recorded stretched about 477 miles, from Texas to Mississippi in 2020. The longest-duration megaflash recorded stretched along the Uruguay-Argentina border for more than 17 seconds, also in 2020. Due to their extreme natures, the megaflashes could only be accurately detected from space by NOAA-sponsored satellites. Because cloud-sourced lightning is the most familiar to us, it's easy to conclude that moisture is required for lightning to form. Because rainwater is partially ionized due to its impurities, it does make a fair electrical conductor. But lightning can occur in completely arid, even water-free environments, so no rain or other kinds of precipitation is absolutely required for lightning to take place. If lightning can form without humidity, then how about in the vacuum of space? Lightning can only occur if there is sufficient electric field strength to overcome the distance between the potential sources and the type of material dielectric between them. While it's possible, lightning is quite rare to witness in open space.

Van de Graaff generator

Lightning behavior There are reports of instances in which it seems like lightning doesn't follow the same laws of nature that everything else does, or at least not how we humans might expect. The fact is, lightning obeys the laws of physics like everything else, but the high-energy discharge that comprises a big lightning flash requires special considerations that often fall outside daily human experience. Like all electrical phenomena, the energy in lightning follows fields, which are completely described by Maxwell's equations and related mathematical models. As mentioned in the previous section, lightning can only occur if the electric field strength of the imbalance between the cloud and ground exceeds the dielectric strength of the air between them for the given distance. For example, say you've installed on your roof a metal L-shaped bracket as a lightning rod, with one end of the bracket connected to Earth by a copper wire. The bracket is L-shaped because, maybe, you want part of it to point skyward, but part of it had to be installed around a soffit. The hope was that ligtning would strike the bracket instead of your house, but during an electrical storm lightning struck the bracket and jumped from the skyward-pointing section to the other end of the bracket. And because your soffit was between the two bracket ends, the soffit caught fire and burned down your house. In 1887, the Royal Society of Arts approached Oliver Lodge and asked him to investigate this exact seemingly contradictory behavior. Why would lightning prefer to take the path of greater resistance and jump to another portion of the metal bracket through the air, rather than going through the bracket, which is the path of lesser resistance? It's because much of the high energy of a lightning discharge follows the path of lesser field resistance, not the path of lesser conductor resistance. Even so, according to Kirchoff's Current Law, lightning, like all electricity, will follow all connected paths (inversely proportional to their impedances), not just the one with the least resistance. Behaviors like this cause many people to feel that lightning is "unpredictable" or that it "does what it darn well pleases." One other consideration that contributes to the confusion by many is that lightning consists of transient components of a huge spectrum of frequencies, including RF (radio frequency) signals. One of the two major results of the high frequency spikes is the skin effect, which momentarily forces much of the current to flow near the outsides of conductors, resulting in greater conductor impedance, because it has less conductor cross-section through which to flow. When lightning current high-frequency components encounter a conductor of such high impedance, yet are within sufficient physical proximity of another, lower-impedance conductor of lower electric potential, they will often cause the air between the conductors to ionize and form their own low-impedance path and "arc" between the conductors. Reducing the possibility of such high-frequency transient components from causing damaging arcs requires the grounding system to use large or heavy-gauge wiring and interconnecting conductors in an attempt to lower the conductor impedance by providing for greater current density skin depth. Many who have connected a small-gauge wire between their antenna masts and a ground rod below it have fallen victim to a false sense of security, believing that they're adequately protected from lightning. While lightning is forming, it seeks an electric potential of opposite polarity. As its stepped leader makes its way to Earth, many upward streamers from objects below make their way to meet the leader. Which streamer(s) are selected for the discharge event depends on several factors, including the potential differences, distances, and path impedances. The lightning leader tends to favor the proximity of the streamer(s) that provide the optimum path for the discharge, but the streamers can originate from a chain-linked fence, the dirt, and yes, your antenna. Even though your antenna might be "closer" to the charge-filled cloud, the leader might choose a streamer rising from your nearby gas meter instead, simply because its streamer had encountered a lower impedance path on its upward climb. For these reasons, one object does not "attract" lightning more than others, but I realize this might just seem like semantics. The point is that the electric potential difference between the leader from above and a streamer from a metal shed sitting next to an antenna could easily force the shed to be the chosen main path to ground, and you, the amateur user, will likely have little control over that selection. Lightning strikes where charges accumulate, and that accumulation can be due to moisture, pointedness, isolation, or just plain happenstance. On the other hand, an upward streamer emerging from an upward-pointed pointy object forces a large concentration of the electric field (due to increased charge density) into a smaller area, enhancing the streamer's electric potential, and making it a more likely choice should a leader form within striking distance. This is the principle behind lightning rods, which point skyward from many buildings, bridges, billboards, and street lights. Another unique lightning phenomenon is ground current, which is the spread and confinement of the static discharge through the relatively low impedance path of the topsoil or sod, giving the scorched soil the appearance of a lightning bolt painting. While it's responsible for the killing of numerous livestock annually, it's also responsible for more human deaths and injuries than any other lightning event. Many other unusual and strange lightning behaviors are manifested because of upper-atmospheric, conductive, and other environmental factors, which I will not explore here in any detail, but leave to the time and curiosity of the reader. These include sprites, blue jets, elves, superbolts, and ball lightning.

Fun lightning video Pointy conductor Golf course showing ground current pattern following a lightning strike

Where and when will lightning strike? On one hand, taller objects are more likely to get struck by lightning than shorter ones. On the other hand, tall objects do not always get struck by lightning. In fact, the ground in an open field can commonly be struck while nearby trees remain untouched by lightning. Static electric charge is not always spread evenly across terrain, even if it appears large and flat; in fact, the charge often collects in clumps, which seems to defy electrical sense. Lightning can occur any time of day, but is typically more frequent in the afternoon and evening during spring and summer, due to daytime heating. Over the ocean, lightning tends to occur more in the early morning before dawn. Lightning can also occur during a snowstorm in a rare phenomenon called thundersnow, producing the mixture of thunder and lightning just like in a summer storm. Some parts of the US more susceptible to lightning than others. States such as Florida, Texas, and others close to the Gulf of Mexico seem to encounter more frequent and more severe lightning than other locations. Worldwide, the most severe and frequent lightning (recorded by NASA) can be found in Venezuela, Colombia, Democratic Republic of Congo, Pakistan, and Cameroon. If you aren't seeing the pattern, these hot spots are located closer to the Earth's equator than other locations, and so tend to be warmer. Summer tends to be the most active time of year for lightning in most places. The warm, moist air and increased atmospheric pressure that typically accompanies the season contributes to an environment in which large amounts of charges can bring imbalance to clouds. The warmer ground causes the cold air above to become unstable, allowing air to rise rapidly, leading to a thunderstorm. The rapidly rising air can then increase the amount of triboelectric charge that's accumulated in the storm, and before long the electric field potential becomes great enough to initiate the discharge process. Bodies of water, such as lakes, ponds, oceans, and swimming pools are good electrical conductors because they're heavily ionized by impurities and dissolved salts. When storm clouds pass overhead, the water easily present themselves as positively charged counterparts to the negatively charged clouds. Finally, about 78 percent of people killed by lightning are male, so when you're out and about on a cloudy day, try and stay away from men, at least when they're out golfing. 😀

What is a direct lightning strike? Seems like many people are uncomfortable discussing lightning and its effects, probably because they don't really understand it or because they have so little control over it. So, they attempt to excuse their insecurity or lack of knowledge of mitigating lightning events by separating them into a "direct" strike and something less. Hmm...so, what exactly is a "direct" lightning strike, compared with a lightning event that's not so direct? To be fair, NOAA defines a "direct strike" as one in which the object being struck becomes part of the main lightning discharge channel, when compared with a less-direct strike, such as a "side flash" or other types. Let's say that distance between my finger and your nose was 4 mm, which means my electric potential was 4 mm x 3000 volts/mm = 12,000 volts. I have no idea how much current went through your nose, but since you likely survived the spark, I'm going to say 100 mA, the Westinghouse-provided threshold of death. The resulting power is 12,000 V x 100 mA = 1200 watts. If the spark lasted, say, 1 µs (according to Wikipedia), then the amount of energy transferred was 1200 W x 1 µs = 1.2 mJ (millijoules). According to NOAA, a typical outdoor lightning event reaches about 30,000 amps and 300 million volts, and 300,000,000 V ÷ 3000 V/mm = 100 meters is therefore the typical discharge distance. The resulting amount of power is 300,000,000 V x 30,000 A = 9 GW (gajillion watts). If the lightning discharge lasted, say, 2 seconds (ibid), then the amount of energy represented is 9 GW x 2 s = 18 GJ (gajillion joules). Because NOAA considers this type of discharge "lightning", I suppose we should too, this time because they're government-sponsored, and of course they're always right. Now we come to the heart of the matter. Does 1.2 mJ constitute the energy transferred in a "direct" lightning strike? Does 18 GJ of energy transfer constitute a "direct" strike? Whether the answer to each question is a Yes or a No, we first need to ask where we draw the line. Maybe an order-of-magnitude table of scientific terms like the following can help: Energy How direct of a strike 1.2 mJ Not a direct strike at all 3.0 J A semi-pseudo-indirect strike 7.6 kJ A mildly-direct strike 5.2 MJ A kind-of direct strikey thing 18 GJ Definitely a direct strike 49 GJ All doubts about directness vanish As you can see, "lightning" is nothing more than a sudden and transient discharge of static electricity, and its severity can vary from a carpet spark to a big flash across the night sky. So, when you hear or read somebody say that a device (such as a lightning arrester) can protect you against static discharge, but not against a "direct strike", you need to consider the above data and ask what is meant by a "direct" strike.

How to minimize the adverse effects of lightning The bottom line is that there's quite a lot you can do to protect your equipment from lightning. Of course, if the lightning bolt is strong enough, your protection is limited by the amount of energy it can handle / redirect / absorb, versus the energy contained in the bolt. Now you know why some amateurs brag that they have never had lightning protection, and have never had their stations affected by lightning, while some well-funded television stations that have rigidly ascribed to Motorola R56 standards have been melted down to an iron slag heap in less than a second. If you're fortunate enough, your station will never encounter lightning that's strong enough to do much damage, but why take the chance? So, what can you, the meager amateur, do to protect your gear from lightning? The answer is Your reasonable best. Yes, you can go to the extreme of protecting your station by subscribing to the industry standards of commercial or military radio equipment, if you can afford the cost and the time. Or you can compromise and accept a little less protection because you're not rich and would like to get your station up and running in a week or less. Ok, so what's reasonable? Here's a recommended list of things you can do to achieve that reasonable best: Drive a ground rod into the dirt just below each rooftop antenna, and connect solid bare 4 AWG copper wire between each ground rod and its antenna mast Drive one more ground rod into the dirt just outside your shack (radio room), unless one of the above rods is already there Install a ground panel in your shack Connect all your ground rods together and to your electrical service panel ground with solid bare 4 AWG copper wire Install a *surge protector ("lightning arrester") on each ground rod that's attached to an antenna mast and run the coax to that antenna through the surge protector * I don't recommend the "in-line" type of surge protector, because I've encountered very few that provide the necessary protection (minumum number of joules). I highly recommend protectors made by PolyPhaser, Alpha Delta, and Morgan. By the way, the purpose of a surge protector ("lightning arrester") is not to stop lightning in its tracks, but 1) to provide built-up atmospheric static charge at your antenna a path to ground and 2) to prevent the complete formation of lightning (upward streamers, actually) at your antenna. If your electrical "service" is on the other side of your house, or if your antenna tower is many yards from your house, you might find it's too impractical (indeed, counterproductive) to run a grounding wire between your mast and your service. Also, if your ground rods and/or service are separated from each other by barriers, such as an RV pad or shed or fence, you might also need to establish an isolated grounding system for them. At this point, I would normally suggest asking a licensed electrician for the best advice, and while I've known many terrific, competent electricians, I've discovered that there are a few who either don't have a clue or pretend they do, and offer bad advice, so ask around if you don't know one.

Unplug or leaved plugged in? Many well-meaning amateurs, even those who work for ARRL, advise unplugging your coax (coaxial cable) when a storm approaches. My take on this advice is caveated with an "It depends" clause. If your station is protected as described above (coax through a surge protector, bonded ground rods, grounded masts, etc.), then feel free to unplug away. But if your station doesn't have the minimum protection I've outlined, unplugging your coax is actually more dangerous than leaving it plugged in. Allow me to explain. On one hand, leaving your unprotected coax plugged in during a powerful lightning event can channel the discharge through your equipment, potentially destroying it and the gear connected to it. On the other hand, unplugging your coax while it's unprotected can result in a large spark between your coax and your gear, continuing its 100-plus-meter journey between your coax and your equipment, even though it might be separated by a glass jar, and subsequently set stuff in your room on fire because of the extreme heat generated by the spark. I mean, lightning that has traveled a hundred meters is not likely to be impeded by a few feet of air and a tenth of an inch of glass. So, without protection, the same spark can likely take out either just your equipment (sad sacrifice) or your entire house (sadder). The question of whether to unplug your equipment is not confined to coaxial cable, but is also relevant to other appliances that are plugged into an AC (wall "mains") outlet. In the US, much of today's household outlets are outfitted with a third-prong ground that's bonded to earth ground at the panel or service. In most cases, that household ground will help protect your plugged-in gear, but if you have doubts about your house ground, or if you're simply worried about your expensive TV being fried by lightning, feel free to unplug your appliance from the wall.

Will my outdoor antenna attract lightning? Without getting confused by semantics or double-talk, let's address one of the largest concerns of radio amateurs who want to improve their radio performance, that is, whether installing an outdoor antenna increases the probability of being "selected" by lightning for discharge, over other, surrounding objects. Let's discuss that question in three parts: whether your antenna will draw lightning, how your ungrounded antenna affects that supposed attraction, and how grounding your antenna changes the game plan. First, because an antenna is a good conductor of electrical current, it can easily form a pathway that allows the discharge of the large pool of collected ionic charge, leading us to believe electrical energy is somehow attracted to it. Your outdoor antenna will not draw more lightning to it than will surrounding objects, like a magnet will "pull" iron filings toward it. It's simply available, should the opportunity arise to conduct the current. Second, if the antenna is not grounded, that charge collection can grow until the electric field intensity between the cloud and the antenna overcomes the air's dielectric strength, resulting in a dangerous, brilliant display. So, not being grounded will not contribute to the attractiveness of lightning to an antenna, but it can allow its electric potential to rise unchecked. Third, if the antenna is grounded, much of its collected charge will likely be drained to Earth before enough is built up to lightning potential. So, being grounded will not contribute to the attractiveness of lightning to an antetnna, because lightning is attracted to electric field potential, and a grounded antenna possesses so little as a result. The three dominant factors that make a lightning strike increase in likelihood are height, pointedness, and isolation (standing alone, separated from other objects). If you happen to be out in the open desert operating all by yourself, for example, chances are good that your station will satisfy all three of these likelihoods. As the electric field is spread out among a large open field or the desert, it concentrates on pointed objects, on vertically higher objects, and on objects that are isolated from others. The concentration is what increases lightning strike likelihood, not whether it's grounded. The idea behind grounding, however, is that should lightning "choose" to strike your antenna, rather than something else, much of its current will be directed to ground. So, will your antenna attract lightning if you're operating portable out in the open? Technically, it will not, but lightning might still select your antenna over other objects because of its pointedness, its height, and its isolation. So, should you ground your antenna when you're out operating portable? On one hand, if you know that lightning is likely, do not erect an outdoor antenna, or take it down if it's already up. On the other hand, if lightning is not in the forecast and you want to drain wind static, route your coax through a surge protector that's bonded to a conductive rod driven into the ground near the base of its mast. By the way, my use of terms such as "selection" and "choice" is not the suggestion of the ability on the part of an electrical discharge to make a conscious choice. Like placing a strong magnet between two other nearby strong, stationary magnets, the one in the middle must somehow "choose" to migrate and attach to one of the stationary magnets, but that "choice" is made by natural physical consequence (proximity, strength, etc.), rather than by conscious reasoning.

Popular lightning myths Like so many mysterious naturally occurring phenomena, discussions about lightning are often encumbered by numerous myths, a few of which I list here: Installing an antenna on my roof will attract lightning (Erecting an antenna on your roof will not "attract" lightning. See the previous section.) Grounding an object will make it more attractive to lightning (Saying that a grounded object will attract lightning more than other objects is like saying an apple covered in Kevlar will attract more pellets than surrounding apples if you shot them all with a shotgun.) Lightning current follows the path of least resistance (According to Kirchoff's Current Law, lightning follows all electrically connected paths inversely proportional to the path impedances.) If it's not raining or you don't see clouds, lightning won't form (Clouds can hold a lot of charge, which can result in a strike whether or not it's raining. But the heavy static potential does not depend on clouds to produce a lightning strike.) If you're caught outside in a lightning storm, you should seek shelter under a tree (Your body tends to exhibit lower impedance than trees and other vegetation, and can be a good conductor for a side flash.) Metallic structures and objects attract lightning (Metallic objects do not attract lightning any more than other objects, but they can more easily produce upward streamers, which increase their likelihood of completing the lightning path.) The rubber tires on a vehicle will protect you from lightning (A vehicle can indeed protect you, but it's largely because of its metal body enclosure, not the tire material.) A highly rated surge protector power strip will adequately protect my equipment (A high-joule surge protector outlet or power strip can indeed provide some level of protection against power line surges, but does little to protect against lightning.) If lightning is striking nearby, you can avoid getting struck by crouching down or even lying flat on the ground (The discharge needs to get to ground, and if your body is lying in the way, it might not be for long. Also, ground current is more likely when your body is spread between farther points than when you're standing.) Lightning only strikes the tallest objects (Lightning can discharge through any conductive object that possesses lower electric potential than that of the source.) Lightning never strikes twice in the same place (Ok, that's an old one that nobody believes anymore. On the other hand, a single lightning "strike" actually consists of multiple discharges through the same path.) Lightning victims can become "electrified" and carry a residual charge (Another one I thought nobody still believed until I actually heard it perpetuated by a licensed electrician on 12-11-2024. It's perfectly safe to come in contact with a lightning victim, assuming you two are in a safe environment.) Undoubtedly, some items on this list will make a few experts, real or otherwise, feel a little uncomfortable. That's good, because those people have three options: a) dismiss me as a nutcase, b) contact me and straighten me out (I don't know everything, and welcome factual corrections), or c) learn something new.

Protecting yourself from lightning If it's not already obvious, a discussion about lightning protection wouldn't be complete until I reminded you that lightning can be dangerous enough to send you to an early grave. When you hear thunder, it's generally close enough to kill you, so let the sound of thunder be your early warning that you are within striking distance of a lightning storm. Sound travels about a mile in five seconds here on Earth at STP. So, once you see the flash, count the number of seconds until you hear the thunder, then divide by five. That's the approximate number of miles it is from you. If it's within three miles, seek shelter inside a sturdy, enclosed building. A few tips for when lightning is nearby: As the saying goes, When thunder roars, go indoors Don't stand under or near a tree during a lightning storm; don't stand near open water, hilltops, or mountain ridges while lightning is striking within a few miles of you Don't seek shelter in metal or open structures, such as metal sheds, beach shacks, pavilions, carports, baseball dugouts, or your front porch Don't bathe, shower, or stand near plugged-in electrical appliances or landline telephones Don't stand outside near utility poles, towers, guy wires, or tall buildings, even though they might seem professionally "grounded" Avoid close proximity to conductive objects, such as barbed-wire and chain-linked fences, metal conduits, street signs, swingsets, and metal troughs Protect your pets by removing metal collars and leashes, or better yet, by bringing them indoors instead of leaving them in outdoor shelters

Summary Static electrical discharge can occur between objects of unequal electric potential in varying intensities, of which lightning is perhaps the most extreme example. Lightning is a naturally occurring sudden and transient transfer of such electrical energy, and is often destructive to an object through which the energy transmission takes place. Like all other natural phenomena, lightning strictly follows the laws of physics, but its behavior can appear inconsistent or confusing if an observer does not account for high-frequency transient current effects. How to protect your gear from lightning is not always obvious, and protecting your person is often less intuitive. Protecting equipment involves proper grounding and bonding, while protecting people requires a little knowledge of how to properly shelter during an electrical storm. Lightning myths are quite prevalent, and distinguishing the facts from the fiction could save your radio, and even your life.

References [1] What Creates Static Electricity? American Scientist (Volume 100, Number 4, page 316), Meurig W. Williams, 07-2012. [2] Dielectric Strength of Air The Physics Factbook, Alice Hong, 2000. [3] What Are the Different Types of Lightning? Treehugger, Russell McLendon, 05-14-2019. [4] New WMO Certified Megaflash Lightning Extremes...Recorded from Space American Meteorological Society, Michael J. Peterson, et al, 05-10-2022. [5] Gruesome History of Electricity Provides Insight for Businesses Fordham Now, Patrick Verel, 02-05-2019. [6] Lightning Safety Tips and Resources National Weather Service. [7] Lightning safety: 10 myths—and the facts Insurance Information Institute. [8] Lightning Safety National Oceanic and Atmospheric Administration, 10-03-2023. [9] Wikipedia reference: Lightning [10] Wikipedia reference: Static electricity [11] Wikipedia reference: Triboelectric effect [12] Wikipedia reference: Lightning rod [13] Lightning Science: Five Ways Lightning Strikes People National Oceanic and Atmospheric Administration. By the way, not truly references, here's a club presentation video and the PPT slide show for it. Finally, some lightning apps you might find useful: Lightning Maps Weather Loop Lightning Strikes

About Noji I am not an expert on lightning. Nor am I a physicist. I'm an engineer, having graduated as an Electrical Engineer in 1989 with a love of physics and an interest in lightning safety. I don't know everything about lightning, but I know a little bit about it, and I believe I know how to find out the rest. I'm a member of the Church of Jesus Christ of Latter-day Saints (Mormon), a licensed ham radio operator, and I believe we need to be armed with accurate knowledge when it comes to lightning protection.