Electrocution via Earbuds?!?! Reports of death from multiple sources. - Page 1
Forum section: electronics / general

author: PhiltheHorror
author_rank: Newbie
timestamp: December 11, 2018, 08:15:09 am
content: Hi all,I read an article today about multiple cases that some unlucky folks got electrocuted from their earbuds. Yes, their earbuds!I'll link the article below, but it seems this has happened multiple times in multiple different countries, including one case in Australia. All the unfortunate victims were using their ear buds on a mobile phone while charging via mains power.Anyone know more about this or any of these cases? With all the super dodgy mobile phone power supplies out there, is it possible this could be more of a problem?Here's the source article:https://www.vice.com/en_us/article/pa5mng/a-16-year-old-has-died-after-being-electrocuted-by-his-headphones

author: JackJones
author_rank: Regular Contributor
timestamp: December 11, 2018, 08:22:24 am
content: QuoteI knew this was the case before even reading the article.A properly made charger from a reliable manufacturer should not have faults like this. There are some seriously dodgy power supplies out there, it's just not worth buying unknown rubbish from unknown manufacturers or sellers.Some of the 5V supplies even use a capacitive dropper. That means no isolation between low voltage and mains, no good at all.

author: bd139
author_rank: Super Contributor
timestamp: December 11, 2018, 10:19:05 am
content: Yeah there are some horrors out there.I think the worst thing I saw was a hooky NiMh charger my father bought which blew up. When I dismantled it, the live terminal had broken off the PCB and was floating around. 4mm to the left it hit neutral and went bang. If it had gone 4mm to the right it would have hit the ground plane on the board and applied mains potential on the negative terminal of the batteries. Dead user.

author: PhiltheHorror
author_rank: Newbie
timestamp: December 11, 2018, 07:42:31 pm
content: Incredibly scary considering how commonplace these bullshit power supplies are (atleast here in the US). Every corner store and gas station has a pile of them.

author: rsjsouza
author_rank: Super Contributor
timestamp: December 11, 2018, 07:52:03 pm
content: From time to time I throw some of these BS chargers in the trash. I tend to keep my "official" chargers at hand (Amazon, Samsung, LG, etc.).Years ago my dad bought one of these tactical flashlights with a 18650 battery and a charger. The flashlight itself was fine, but the battery was cheap and the charger was a simple resistor between the 5V and the battery. The plugpack was equally cheap, with a loose solder blob inside. I bought an Nitecore intellicharger for me and for my dad.

author: ucanel
author_rank: Regular Contributor
timestamp: December 11, 2018, 08:24:41 pm
content: Some dodgy chargers have no isolation betweenprimary and secondary of the transformerother than the micron thick cable coating.The channel below has most of this kind of tear downs and schematics.https://youtu.be/ehYYoU13i-I

author: ebastler
author_rank: Super Contributor
timestamp: December 11, 2018, 08:52:39 pm
content: I can see how a cheap, crappy power supply could arc over, and send mains voltage to the 5V output. But all the earbuds I have seen are plasticky affairs, which don't put the user in contact with any metal parts when worn. And larger headphones have ear pads made of non-conducting material.So I struggle to see how the headphones would electrocute you, even with main voltage routed to them?

author: Kleinstein
author_rank: Super Contributor
timestamp: December 11, 2018, 09:02:52 pm
content: Not a real surprise given the poor USB chargers one sometimes finds. Though not everything was better in the old days: I once too apart an old black and white TV set, and to my surprise there was no visible isolation for the head phone jacket and not isolation for the circuit from ground (which was common back than). So I luckily never used head phones.I have not seen a bad charger in real life, but some of the videos on the web a really scary - up to the point of having a common heat sink for primary and secondary with no insulation - so essentially on the oxide layer an the aluminum as a poor contact.So they should include the warning of no using head phones while charging, unless one has properly isolated ear plugs.

author: cdev
author_rank: Super Contributor
timestamp: December 11, 2018, 09:07:20 pm
content: Companies that make and sell obviously dangerous chargers should have to compensate the victims of their stupidity no matter where they are, the victims are, or how little the charger was sold for.

author: Gyro
author_rank: Super Contributor
timestamp: December 11, 2018, 09:09:36 pm
content: Quote from: ebastler on December 11, 2018, 08:52:39 pmI agree, it does sound unlikely that plastic earbuds, what with silicone tips or whatever would break down to the body at mains voltage. At a few kV, yes. Maybe surface moisture would drop the insulation resistance a bit but it still sound fishy.Deathtrap chargers / adapters of course are now sadly a fact of life. EDIT: maybe modern cheap earbuds are equally crappy.

author: cdev
author_rank: Super Contributor
timestamp: December 11, 2018, 09:21:49 pm
content: Before they break completely, sometimes the 'shield' conductor of crappy headphones gets exposed. This almost always happens at one of the two ends.For people that have some decent electrical tape around, who know how to use it, (stretch it first) they can sometimes be repaired and last a bit longer.But no way should mains voltage ever be allowed to become present there!

author: rsjsouza
author_rank: Super Contributor
timestamp: December 11, 2018, 09:23:41 pm
content: I can imagine this is quite plausible; I have earbuds that have a wide exposed metal area touching the skin. That and the possibility of having frayed cables.Regardless of the quality of the charger, I imagine it would be very dangerous to be exposed to a metal part in the scenario below (extracted from the article)Then, a month later, a 22-year-old man in the Indian village of Pandyo was listening to music from a plugged-in cell phone while the electricity in his house was cut off. When the power came back online, the man received an electric shock through his headphones and was also killed, NDTV reported.The transient surge can be quite unpredictable in these scenarios.

author: MrMobodies
author_rank: Super Contributor
timestamp: December 11, 2018, 09:31:42 pm
content: I came across a cheap usb charger that was bundled with some cheap noname MP5 players that a customer got from Ebay.One of the USB chargers worked initially but stopped working and the one of players didn't power up. When I tested the other charger that did work it couldn't even handle a 400mah load without dropping to 2 - 2.4v and it kept on spiking over 6v with no load. It was cheap and light and told them throw it in the bin and you think that is cheap and nasty but what about the safety of the batteries inside those MP5 players.

author: ebastler
author_rank: Super Contributor
timestamp: December 11, 2018, 10:00:35 pm
content: So that's why Apple in their inifinite wisdom dropped the standard headphone jack.Only a single proprietary connector, and you get the choice toeitherconnect a charger,orconnect your headphones. Safe at last!

author: MrMobodies
author_rank: Super Contributor
timestamp: December 11, 2018, 10:14:06 pm
content: Quote from: ebastler on December 11, 2018, 10:00:35 pmAnd you get this:https://www.bbc.co.uk/news/uk-39307418QuoteResting a charger on his chest in the bath so he can use his phone and he got grounded to earth.

author: bd139
author_rank: Super Contributor
timestamp: December 11, 2018, 10:16:21 pm
content: All health and safety rules come from someone dying or getting mutilated. If you fail to heed the warning then you’re a dumbass. That guy was a dumbass.

author: GregDunn
author_rank: Frequent Contributor
timestamp: December 17, 2018, 12:41:06 am
content: Quote from: Kleinstein on December 11, 2018, 09:02:52 pmOne of the very first pieces of electronics I worked with was a pair of tube amplifiers which I set up as a dual-mono "stereo" rig. I'd been given the amps for free as well as a discarded turntable. All I had to do was build a pair of speakers and I was in business.Many cheap old pieces of vacuum tube gear were powered directly from the mains without a primary transformer of any kind - the idea being that they were intended to be isolated inside a big hunk of wooden cabinetry and couldn't possibly come in contact with the user. Of course, having liberated them I placed them on a shelf side by side. It was critical to ensure that the chassis side was connected to electrical ground on both amps! That way the "hot" side was inaccessible. (Isolation transformers would have cost more than a decent stereo in that place and time) Very few people in that town had neutral wiring in their houses back then, so if you didn't know what you were doing you didn't fool around with mains wiring. I didn't let anyone - not even my parents - touch my gear when it was plugged in because I knew Murphy was waiting to teach someone a lesson.

author: EEVblog
author_rank: Unknown
timestamp: December 17, 2018, 09:56:56 am
content: I was was contacted by a researcher from Snopes about this story, wanted to know if it was possible.

author: amyk
author_rank: Super Contributor
timestamp: December 17, 2018, 01:19:43 pm
content: Quote from: MrMobodies on December 11, 2018, 10:14:06 pmNot the first time that has happened...https://www.eevblog.com/forum/chat/is-this-really-likely/

author: GeoffreyF
author_rank: Regular Contributor
timestamp: December 17, 2018, 03:17:06 pm
content: Well designed chargers, with spark gaps in the PCB and the low voltage part well separated from the mains, are designed to withstand surges which could far exceed normal. I can believe a surge which wouldn't jump a proper spark gap could continue into the earphones with enough energy to electrocute someone, especially in the ear canal with a good path to the brain.Plastic doesn't mean a thing if there is high voltage in the wiring.

author: SiliconWizard
author_rank: Super Contributor
timestamp: December 17, 2018, 03:40:25 pm
content: Actually, many seemingly "harmless" electrical devices out there which are meant to be in direct contact with the user's skin (and especially for extended amounts of time) are completely unsafe as soon as you use them while powered by mains adapters. Even if that sounds excessive, I guess that we could somehow consider that such devices should comply to safety rules close to the ones used for medical devices. Earbuds being close to the brain and some probably with lowish contact impedance (if they are conductive) due to ear canal sweating, you have a recipe for something potentially interesting.Obviously in the case of using a device as in the earbuds example, powered by its charger connected to mains, that can be almost equivalent to plugging the charger's output itself directly into your ear canals in case there is a fault with the charger and insufficient insulation with the rest of the device. Many cheap chargers/mains adapters are complete crap, and some earbuds are actually slightly conductive. Problem is, a lot of them aren't actually properly tested before being put on the market.A few decent manufacturers have taken steps to drastically limit the risk (for instance by making it impossible to use earbuds and a charger at the same time), but a lot haven't. And stating in the manual that it could be hazardous... well. How many people actually read manuals?

author: ebastler
author_rank: Super Contributor
timestamp: December 17, 2018, 07:52:42 pm
content: Quote from: GeoffreyF on December 17, 2018, 03:17:06 pmI would argue that it depends a lot on the level of the voltage and the thickness of the plastic.But your sweeping statement sounds much more manly, of course.

author: floobydust
author_rank: Super Contributor
timestamp: December 17, 2018, 08:04:56 pm
content: We don't know the safety limits for shock current at the human ears. The brain does control the heart to some extent. Shock current is known across the hands, chest etc. for heart muscles to get directly affected at 50/60Hz.But these chargers can also output high voltage spikes at >50kHz (mosfet drain coupled to secondary) which have capacitive currents that would electrocute.Here the electrocution path might be from ear to hand, although earbuds are plastic and somewhat insulated so I am a bit skeptical.Electroshock therapy is 600-900mA across the temples- a totally different path.edit: looked at ECT

author: PlainName
author_rank: Super Contributor
timestamp: December 18, 2018, 01:43:56 am
content: Quote from: EEVblog on December 17, 2018, 09:56:56 amAnd...?!!BUSTED!! video coming? I'm sure your assistant could act as a test subject

author: aabbcc
author_rank: Regular Contributor
timestamp: December 21, 2018, 11:21:00 am
content: Quote from: ebastler on December 11, 2018, 08:52:39 pmMine are metal albeit with rubbe ear pads

author: coppercone2
author_rank: Super Contributor
timestamp: December 21, 2018, 11:30:45 am
content: how are australian homes with this and more advanced safety standards?You have arc fault interrupts and GFIC right? and big input MOV/GDT or something?Do these home-level protectors protect from this fault (i.e. input surge protection for the home preventing a breakdown voltage from forming in the charger) or AFI detecting a breakdown?

author: Rerouter
author_rank: Super Contributor
timestamp: December 21, 2018, 11:41:48 am
content: All new Australian installations to wet areas are meant to have RCD (Residual Current Device) breakers, that trip at less than 20mA in less than 50ms,The issue is that there is a lot of older houses from before this requirement came into be, and even more home-gamer installs who replace out the RCD for a normal breaker because there hairdryer keeps tripping out, or something similar, or the RCD was never installed in the first place.If your charger was in an RCD breaker circuit, you would survive in almost all cases, generally its only very young, very old, or people with heart irregularities that they cannot save every time.Still its a pity that these dodgy chargers keep on being sold with very little alternative in actual store fronts, no one wants to pay $40 for a wall charger, but at the same time, when the change for proper insulation would be cents worth of work, why don't they do it? I get profit, but building lethal shit should atleast nudge people away from it.

author: LapTop006
author_rank: Unknown
timestamp: December 21, 2018, 01:13:47 pm
content: Quote from: Rerouter on December 21, 2018, 11:41:48 amMy place still has a fuseboard, and having been a rental for ages, I assume the fuses don't actually have fuse wire in them. It's not until you get places built in the 90's that breakers had become standard, and not until ~10 years ago that central RCDs really became standard.

author: fsr
author_rank: Regular Contributor
timestamp: December 21, 2018, 02:17:20 pm
content: So, all the certifications, and import requirements, and still this rubbish can pass into customer hands?

author: Rerouter
author_rank: Super Contributor
timestamp: December 21, 2018, 08:06:27 pm
content: LapTop006, you know as a renter you are still allowed to pull out the fuse wire holders and replace fuse wire.Also its 1 stand of fuse wire, came across enough with it wrapped around 7 or 8 times. won't save you from dodgy chargers, but should save the wires in the walls from melting there insulation and worse things starting.

author: LapTop006
author_rank: Unknown
timestamp: December 22, 2018, 04:16:12 am
content: Quote from: Rerouter on December 21, 2018, 08:06:27 pmOf course, more sensibly I'd have an agent-bypassing contact with the owner, and if I cared I'd get the panel replaced with modern breakers.

author: james_s
author_rank: Super Contributor
timestamp: December 22, 2018, 06:11:42 am
content: It's certainly feasible with a poorly designed charger. Some of the cheap knockoffs are pretty terrifying really. Nothing between you and the live mains wire except for a fraction of a mm of tape between the transformer windings.

author: daniel5555
author_rank: Contributor
timestamp: December 28, 2018, 01:19:53 am
content: I wonder what's the probability of this happening with someone using a notebook or a desktop PC and listening to music through some headphones or earbuds? That seems to be more likely use-case scenario than listening to music while charging the phone (which always seemed to me to be a bad idea to be honest).

author: Rerouter
author_rank: Super Contributor
timestamp: December 28, 2018, 01:32:11 am
content: If your laptop has a 3 prong charger and the outlet is wired correctly, then there is a lower risk, The reason you get zapped by some laptops is when the grounding is not working. e.g. using an inverter in the car.In these cases however there is a higher risk from the ground being miswired to active. but I would hope that not many outlets miswired this badly exist for long, or far more people would die from using a kettle or toaster each year. A lick of mains does wonders to get people to agree to call in the tradie.

author: james_s
author_rank: Super Contributor
timestamp: December 28, 2018, 06:46:19 am
content: I think the chance of it happening with a laptop or desktop is extremely low. These types of machines don't use ultra miniaturized power supplies requiring very careful design to achieve adequate isolation. 240V mains using a charger the size of those for typical mobile phones is not a trivial thing to design well. Laptop and especially desktop power supplies are usually much larger and making them safe is easier.