Inside a heated shower head. (suicide shower)

Big Clive also did a teardown and analysis of them, including the fault conditions that would make it dangerous [VIDEO] He also did one on a UK-approved unit for comparison [LINK] The units aren't dangerous if installed properly, but they're not many failures from delivering a nasty shock.

The difference is that in Scotland and Europe, it’s just one or two insulated heating elements that the water flows past. There are numerous safeties, overheat protectors, usually an RCD - in short, you’d be very unlucky to get a shock. In South America, I’ve seen two types. One: an element, but it’s uninsulated and has no safety features. This is usually operated by a water pressure switch and operates by heating a thin resistive element up. High danger of faults to earth (you’re earth). The other kind has me rather gobsmacked - the water is the element. The idea is to just pump in enough juice that the water starts to flash boil, and forms a plasma channel that then heats the surrounding water. Ostensibly safe, if earthed, but I really disliked the 60hz skin tingle - later discovered that they’d hooked earth up to the third phase in that house, when I plugged my laptop in. Metal case, leg, funky chicken. I guess the shower is reliant on skin effect to not kill you. There’s a really great YouTuber who is forever tearing domestic appliances apart - it’s actually quite amazing how some stuff is built, both in a good way and a bad way. Links to showers: [LINK] [VIDEO]

Electroboom did a video on the subject. It seems that they are actually safe. Not sure I'd be willing to try it though. [LINK] And bigClive [VIDEO] diodeGoneWild [LINK]

I remember this video [1] from bigclive about it. I had no idea it was so common to have live wires in contact with water. At least they are grounded sometimes? [1] [VIDEO]