A study of lightning fatalities inside buildings while using smartphones [pdf] (2024) | Hacker News Reader

A study of lightning fatalities inside buildings while using smartphones [pdf] (2024)

electricalsafetyworkshop.org

50 pointsbookofjoe60 comments

I found this bit at the start surprising: "Lightning is one of the leading causes of climate-related deaths worldwide. In recent decades, there has been a considerable increase in lightning due to worsening global warming [1], [2]."

Increased lightning makes sense, but I'd still have expected most climate-related deaths to be caused by flooding, heat waves, disease & crop failures, with lightning being a much smaller factor. Do they just mean it's in the top 5 or 10 climate-driven causes, or is lightning really killing people on the same (or greater) scale as these other things?

Unlike those others, with lightning it's directly attributable to weather. That's the only thing I can think that would justify the ranking.

In all cases, the phone was charging at the time.

I usually use my laptop plugged into AC, rather than on battery, but will unplug at the first thunder.

If it sounds like a bad storm, I'll start unplugging other electronics.

I thought I was doing overkill abundance of caution, but maybe it's actually a good idea.

I do the same thing. The 20-30 minutes it takes for a major storm to roll through is not worth the time/hassle/money of getting fried electronics replaced. Surge protector or not, I just unplug them. Since most of my equipment is connected to some sort of device with on/off switch, it reduces the number of plugs that need to be disconnected to 3. I feel like a surge protector is just there for when something happens to mains from human causes. Putting all of my luck on them for lightning is just too much faith in modern manufacturing and faith in companies honoring a warranty on those devices.

Its funny what you can get used to. We had so many storms and general bad weather events growing up, that I don't really give them any thought. Certainly didn't back then.

Out in Seattle, though, if there is a single crack of thunder, everyone is at the windows trying to see what happened. It is almost comical on how this place never really gets a storm.

Does make me somewhat at odds with the crowds that hate firework noise, "because it scares pets." I'm in agreement that it is just obnoxious and I don't miss it. I'm pretty sure thunder was far more frightening for any pets I had, growing up.

All that is to say, probably wise advice on unplugging things. I know that quality of power has gotten a lot more relevant in recent years, such that you should only be worried about very local events. Still, seems safe enough not to take a risk, if you can avoid it.

Living in storm prone regions for most of my life has given me the same habit. All my sensitive electronics get unplugged when storms approach.

Two of my family members have had devices fried by lightning strikes over the years, and not even in regions known for the worst electrical storms.

I keep some portable battery packs handy in case I need to charge a phone, and if I'm working will switch to my laptop and tablet screens.

Of course, one can't conveniently unplug everything (HVAC, big kitchen appliances, etc.) but it's easy enough to safeguard work and lifestyle electronics.

Turning the TV off and listening to the storm is usually a nice change of pace, too.

I'm pretty sure you can just buy various surge protection systems for this, am I wrong?

What if you're out somewhere, do you drive home in a bad storm and unplug it all?

A defining characteristic of lightning is that it jumps the gaps (ie, all the air between the cloud and earth), so I believe it will jump right over surge protection.

If that's the case, wouldn't there be no point in unplugging devices?

I suppose the difference is that surge protection provides a guide to a possible circuit. Whereas unplugging greatly increases the micro-states where you are not in a viable path.

No, unplugging works because cables are antennas. Power cables being disconnected dramatically reduces the ability for the lightning to couple into the device

The device itself usually has shielding, capacitors, transient suppressors, etc… as well as usually designed to make a poor antenna so on it’s own it will be affected much less than when charging

Surge protectors do work, mind you - but only for weaker storms or pulses coming in from the outside power lines. Just by physically being separated from the final device they are limited in how much they can protect from direct coupling

Unplugging works but it's pretty impractical, you basically need to be always awake an always near your devices to make it work.

There is also a risk of electrocution when unplugging a device during a storm.

> What if you're out somewhere, do you drive home in a bad storm and unplug it all?

If we're traveling overnight we'll unplug things before leaving, but otherwise, no rushing home out of concern for the TV :)

30 years of Midwest thunderstorms i never lost a single device to a thunderstorm but i moved to Chicago and now I've lost maybe like, 3 chargers and a VCR that got got in a storm last year.

Sadly I've still been too lazy to upgrade my surge protectors lol

I guess it's another good reason for why I shouldn't have my phone charging in the bed with me while I sleep; the other good reason being battery fires.

And to avoid unnecessary RF exposure.

although anyone saying this outloud likely wont have their mind changed, for the rest of you all that want to remain informed:

cellular devices and radios do not emit ionizing radiation - which is the kind that messes up cells, and nonionizing radiation can only increase heat which is why all devices operate under a power limit

people are studying other potential biological effects of nonionizing radiation and there is zero consensus of there being any. so some people, including some smaller government agencies, exercise caution

What the parent comment was likely referring to:

https://www.snopes.com/fact-check/coil-mattresses-cause-canc...

What is known:

https://www.cancer.gov/about-cancer/causes-prevention/risk/r...

Can you see any potential risks with blasting the body with same frequencies as it uses to regulate itself, while its supposed to be regenerating?

What radio frequencies does your body use to regulate itself?

My liver uses a walkie talkie to communicate with my kidney (the left one).

I mean, maybe, if the body used radio waves to regulate itself, but it doesn't so I don't

Be more afraid of taking a shower or bath during a storm.

Lightning won't take a detour through you, it will follow the path of least resistance.

Yes but if you are covered in electrolyte and standing atop a well-grounded drain pipe, you may just be that path.

Also, lighting is not simple mathematical electricity. It is subject to innumerable, even quantum, fluctuations at the precise moment it chooses to move. Lighting also partially creates its own path as it ionizes air/water into plasma. That's why bolts are jagged and not smooth beams between cloud and ground. It may or may not choose to go through or around you. It is best to avoid needing to ask such questions.

https://youtube.com/shorts/dvVW1e_trW0

“Path of least resistance” is a simplification of ohm's law, and that simplification simply isn't very relevant when dealing with voltages with 7-9 digits and tens of kiloamperes: at those voltages, even high impedance paths will have a non-trivial current (to lifeforms made of bags of saltwater).

And don't forget that an instantaneous discharge of 10,000A will also create a tremendous magnetic field which will immediately collapse, creating voltages that will induce eddy currents in conductors (such as the aforementioned bags of saltwater) that are near the main current flow.

odd choice to be forced to make, but I would prefer being electrocuted to burning my face off.

>Why you should never take a shower during a thunderstorm

https://www.washingtonpost.com/wellness/2025/04/22/showering...

gift link: https://wapo.st/3GjjuO2

If you want to protect yourself from something that hasn’t caused any fatal incidents in 20 years anyhow.

Gift link still paywalls :?

FF Reader mode seems to work.

https://archive.ph/1loN3

While scrolling and charging your phone

> The data collection indicated a worrying series of fatal accidents in Brazil, all concentrated in five months. The recurrence of these accidents in rural regions and the intense sound of the discharge reported by witnesses indicate the proximity and intensity of the lightning during the accidents.

So, rural areas without lightning rods nor any other safety mechanism. Good study that can save lives by taking prevention measures in rural areas in developing countries. But it will probably not affect anybody living in New York.

> But it will probably not affect anybody living in New York.

There are vast swathes of American rural land with too-few and far between lightning rods. Maybe not in NY, I wouldn't know, but near as I can tell no U.S. state requires the installation of lightning rods in rural areas.

If I have been struck by lightning through the phone networks during a storm, and some losses ensued, to whom would I address my complaints?

God?

TL;DR: Don't hold your smartphone while it's connected to a wired charging cable and there's a storm outside.

... when in Brazil?

All the deaths happened in Brazil, your logic is shocking, but sound.

Since the study was authored by brazilians who only used data from brazil, it's hard to tell if the fatalities were enabled by the brazilian electrical system and would not happen elsewhere. Especially given that 4/5 were in rural areas.

It does seem like there's potentially some kind of bad electrical system / lack of grounding issue going on.

typically phone chargers aren't grounded, so probably not relevant? lightning travels through the ground, so i'd expect the ground wires to be rather dangerous. also, neutral is bonded to ground at the meter (at least here)... so also not good?

Neutral bonding to ground is definitely not how it is done everywhere. A proper ground according to modern standards will have a true grounding rod that the buildings ground wiring is connected. Of course wiring predating those standards are a mix of how they are handled. Some older wiring used the buildings metal plumbing as ground which is why people say not to shower during an electrical storm.

"potentially"? ;-)

Look around on the Internet and you'll definitely see how a lot of electrical systems in Brazil are not quite up to North American standards. Grounding is part of it.

My guess is that Brazil’s infrastructure is not that different from other countries, since they run a 60Hz grid I’d imagine they use the system introduced by Edison’s company General Electric.

That's actually a fairly recent (1970s) change, prior to that it was a mix of 50 and 60Hz, 110V and 220V, with no national standard.

Also, rural household wiring is often dogshit all around the world with many places having bad earthing.

Are you crazy! If you die in Brazil, you die in REAL LIFE! https://m.xkcd.com/180/

Brazilian currency being the real, you would kind of die in "real life" indeed

Could also be that Brazil has a lot of high population cities in high lightning zones. Couple that with illegal electric hookups and it sets up a dangerous situation.

tl;dr: Use surge protectors when you care about your electronics and/or your health.

I would not count on a surge protector to save you if there was a direct lightning strike. Even a hefty UPS, but especially not the small ones in a power bar or some consumer electronic chargers.

Better to not have your laptop or phone plugged in at all when using it during a storm.

Surge protectors definitely help handling surges from distant strikes, but they won't survive a more direct one. Lightning measures in the millions of joules, well above what any available surge protector is rated for. Given that lightning is an arc through air, breaking the circuit once the surge has started won't save you if your circuit gets a direct or near-direct hit.

Don't houses have spark gaps for that sort of thing? I don't remember this being a problem since I was a kid, when we used to have to unplug TVs and modems

Edit: come to think of it that's when I moved to New England so it could just be the nonexistence of lightning here. Which I do miss.

My parents lost their treadmill during a storm in a midwest US house built circa 1998. I think the power came as a surge through the grid rather than directly from the environment, though.

Surge protectors are not rated for lightning. There are protection systems for lightning (ham radio operators use them), but they're quite a bit more expensive and also involve driving a copper stake into the ground to establish a preferential path for the lightning.

Which is how grounding systems work in houses as well. Where I live, it's required code to have a 6 foot grounding rod driven into the ground, connected to your breaker panel. That's why modern houses in North America have 3 prong outlets instead of just 2.

New Zealand household grounding legislation[1] also allows a long horizontal grounding wire, or connection to the reinforcing within concrete foundations.

I've only seen rods - likely the easiest solution but also maybe I've not had much exposure to newer builds.

Grounding in very dry areas is more tricky, so US legislation will likely be different in very dry areas - maybe requiring a maximum resistance and testing?

AFAIK in New Zealand neutral is not tied/bonded to earth at the house but only at the substation. That's to (1) avoid the house earth floating to mains voltage in a specific double fault situation (neutral return failed open circuit plus house earthing failure equals danger since the outside of metal appliances are usually earthed), and (2) avoid corrosion due to long term leakage currents. We've also got less tingly 240 Volts here.

I tried to search for some better info on earthing but only found an unreliable source that said:

  There is not one standard ground resistance threshold that is recognized by all agencies. However, the NFPA and IEEE have recommended a ground resistance value of 5.0 ohms or less. The telecommunications industry has often used 5.0 ohms or less as their value for grounding and bonding.

[1] https://www.legislation.govt.nz/regulation/public/1997/0060/...

Good comments on earthing in reply to this thread: https://forums.theregister.com/forum/all/2025/04/25/on_call/...

From comment about UK having three earthing standards:

  TT - Terre Terre or Earth/Earth, where the installation earth is actually connected directly to earth via an earth rod or similar and only phase and neutral run back to the transformer. Very common still with older housing stock, particularly with older overhead cables, though things are gradually being upgraded. The earth in a TT system is high impedance and unlikely to pass enough current to blow a fuse under fault conditions, so a separate safety device must also be fitted which these days is an RCD, and there are all sorts of rules for that

  TN-S - Terre Neutral - Separate, where the installation earth is connected to an earth installation at the transformer, where the neutral is also earthed. This earth is usually conducted over the metallic sheath of an underground cable and can blow fuses without the help of an RCD, though RCDs are mandated domestically for other reasons too

  TN-C-S - Terre Neutral - Combined - Separate, where the installation earth connects to the supply neutral at the service cutout of the installation (and nowhere else), while the neutral is grounded not just at the transformer, but for obvious safety reasons at several points along its path to your house too.

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