UK Scenario where lack of supplementary bonding is dangerous

[Falkus]

So I know why it is done, where it is done and how it’s done, but I’m yet to see a scenario where there is shock danger in a typical bathroom in a dwelling provided a) the main bonding is in place and b) the CPC’s of all circuits are connected together in the CU (as they will be).

Consensus is on an EICR code 2 where there is no RCD for additional protection and supplementary bonding is not in place. What is the potential danger ? What am I missing ?

 

[mainline]

It is, and I'm not exactly short of reasons to condemn this light!

View attachment 116244

I don't think that can be classed as a light any more, more like a jumble of wires hanging out of the ceiling

 

[nicebutdim]

There are plenty of ip rated pendant lights

And there are many more IP20 rated pendant sets hanging in bathrooms.

 

[oscar21]

Surely one of the most important parts of supplementary bonding is to bond the radiator and hot tap/pipe to the cold one. Both the hot tap and radiator pipes could well have a voltage introduced onto them via things like the boiler electrics or immersion heater, the cold could well be isolated from all other pipework yet be at earth potential due to the cold supply pipe coming out of the ground, you could well have 230V across the two taps.

The hot/cold/radiator pipes were the only things that needed to be bonded when I started out and of course there wasn't any RCD on immersion and lights back then, only sockets, so it made sense. It was only later that we had to bond the lights/towel rad/shower etc along with the pipework, this made less sense to me than doing the pipework as everything was effectively bonded together at the consumer unit anyway. I get that a 4mm earth will have lower resistance than the cpc but you were allowed to use the cpc of the thing in the bathroom you were bonding anyway, you could bond the electric towel rad at the spur outside, not directly to the rad and the 1mm cpc acted as the bond, bizarre really some of the regs they come up with.