Electrocution via USB charger

The true source of the electrocution has not been established

Fair enough. Maybe the charger was compliant but the cable was frayed? Maybe the extension cord itself got submerged? Who knows? Does it matter?

The key message is, don't use electric stuff in the bath. Not sure it needs to be any more complex than that.

5V (even 20V) DC from a charger wont kill.
There are reports of burns on the woman's chest.
So she got hit with full 230V AC
The extension lead was in the bathroom, with the end on a wet floor or in the bath.
She had stood up (since she did grip on to something), and it is likly her foot was on the electrified floor, and she then fell back into the bath. Nothing to do with the phone or the charging lead. Might be due to a soaked charger, not the phone.
The real issue here is why the RCD did not trip? There was no mention of an registered electrician's report. No mention that the circuits were inspected and tested for resistance and trip times. WHY?
Since the metal fittings in the bathroom were also involved, where are the ground resistance and equipotential test reports for those?
I know someone who stayed for a while in a house on that street (admitidlly 30 years ago). The electrics were ancient and flakey back then.
In my opinion, there was no RCD on the circuit and the poor woman stood on the wet floor while holding the pipework. RIP.

You don't remember enough :)

A 5V power supply needs a 2.5 Ohm load to generate 2 Amps. A human body have at the lowest 500 to 1500 Ohms, so at 5V you will have between 0.003 to 0.01 Amps. Nowhere near 2.

You're absolutely correct Cordell - I don't remember enough! I just saw the 2A in the OP and waded in there.

Thanks for the input. I'll get ChatGPT to explain all this to me. (as well as how 'Earthing' works because that's also been a mystery to me)

Earthing, which normally is a vital safety feature, is what probably killed her in this case. The fact that the pipework was properly grounded is what provided a path to complete the circuit.

Totally misleading thread title.

The woman had a long extension lead from a bedroom socket brought into the bathroom and she plugged her charger into this extension lead.

She had the charging cable connected from the live 3 pin socket into her phone via the charger.

She dropped the phone into the water whilst charging.

Now I can see the husband wants to try and convince himself that his wife had no fault whatsoever for the rather stupid and very dangerous action. He'd prefer to blame the big multinational company.

Whilst the inquest probably wanted to state the obvious, but did not out of courtesy to the husband. But reding between the lines, it was entirely her fault for doing something so dangerous and hopefully anyone else who thinks its fine to bring a extension lead into a bathroom whilst having a bath or shower will think twice

I had a long post written about this on another thread yesterday(may actually have been Reddit tbh), but there really is way too much unanswered to have a proper technical discussion on it.

What's bugging me is:

1. If the easiest path to ground was though the victim, how was the charger even working at all? I would have expected that any short would find the easiest path to any one of the four ground pins on the USB-C, or the shield itself. If those were broken, the battery wouldn't be charging.
   
   According to the engineer, "no fault with either the phone, the charger or the cable". In that case - by design it shouldn't be shorting to a person
   
2. Even accounting for the water, and the full output of 19V - is that really enough "push" to actually induce say 0.1A across the heart? It think that's unlikely, but possible.
   
3. The report leaves out very significant details. What phone, what spec of charger? Was it tested? Was in CE certified? "No problem" is way too generic a statement IMO.
   
   Not to speak ill of the dead, but the line between misadventure (a soaked 220V cable), and totally unexpected death is very blurred here. For people to actually understand the root cause here, and define proper safety standards and regulations, leaving out details is unacceptable. ie: my phone is "waterproof" my phone can also charge other phone over USB-C. Am I in danger? What about a battery pack? etc.

I will say two things though:

1. In work, the guy next to me knocked his USB PD laptop dock off his desk, damaging the connector at the laptop side. It shorted inside the cable connector and burned it very badly - much more than I would have expected tbh.

2: I have a Worx portable pressure washer. It's not USB, but it's a AC-DC charger which outputs 20V @ 400mA. The battery itself can supply much more of course. I had forgot to charge the battery in advance, so while washing the car I came inside to check the charge level. My hands weren't soaking wet, but not dry either. My shoes were likely wet alright. The battery may have been a bit damp from being in vicinity of me washing the car, but it certainly wasn't visibly wet at all.

While it was plugged in, I pressed the test button to see what the charge level had got to, and I got a fairy big shock from it. I've got shocks from capacitors all the way up to 220V, and this wasn't on the low end of things. To be honest I wasn't expecting that level of shock at all from just 20V.

(my charger is the UK plug model, but I suspect the third pin isn't connected to anything.)

You didn't get that shock from the battery, but rather from the live mains. Only that can create a circuit that involve passing current through your finger, your body and ground. What happened exactly may be something similar to this case here, water everywhere.

In order to get a shock, you need your body to be part of a circuit. A bad shock needs a large part of you to be part of the circuit e.g. live-hand-torso-leg-ground.