House probably not earthed

[JohnW2]

I'm a bit lost by this. The gas bottle sits outside, it connects via a rubber/copper pipe to a free-standing gas cooker just inside the door.
Are you saying the cooker and or the bottle ought to be earthed? Why? How?

Sorry it's complicated!

If the gas bottle were potentially in contact with the ground and the hose were made out of electrically conductive rubber (some are) then you theoretically would need to bond (connect) the metal pipe, where it enters your house, to the electrical installation's 'earth'. However, as I just mentioned, if you could be sure that the hose was not electrically conductive, then there would be no need for such bonding and, indeed it would be arguably better not to have it.

Is there anything written on the rubber hose which gives any indication of whether it's electrically conductive?

Kind Regards, John.

 

[JohnW2]

I'm a bit lost by this. The gas bottle sits outside, it connects via a rubber/copper pipe to a free-standing gas cooker just inside the door.
Are you saying the cooker and or the bottle ought to be earthed? Why? How?

No, it shouldn't.

I think that black LPG hoses, such as the one in your photo, are quite often conductive - the orange ones are less likely to be conductive, but still could be.

Kind Regards, John.
Edit: I've just looked at an orange LPG hose. The orange is just a sheathing over black rubber - so, without testing, I wouldn't be too confident that it's non-conductive.

 

[clifford1]

Now I'm even more lost!
Are we still talking electricity/earth/shock? There is no electricity near the cooker, the bottle or the pipe. This isn't an underground pipe, such as is often used as a convenient earthing point for the house electrics, just a bit of 1/4" pipe stuck through the door frame. It's like having a camping gas stove inside the tent with the bottle outside.

 

[JohnW2]

Now I'm even more lost!
Are we still talking electricity/earth/shock? There is no electricity near the cooker, the bottle or the pipe. This isn't an underground pipe, such as is often used as a convenient earthing point for the house electrics, just a bit of 1/4" pipe stuck through the door frame. It's like having a camping gas stove inside the tent with the bottle outside.

OK - I understand your problem, and will try to explain.

The pount is that, as you have noted, the 'earth' of your electrical installation (to which things like the metalwork of your electric kettle will be connected) is actually derived from the incoming neutral conductor, not a direct connection to 'true earth'. Under certain fault conditions in, the electric potential (voltage) of that incoming neutral (and hence everything 'earthed' via the electrical system within your house) could rise to a dangerous level above 'true earth' potential. If, under such fault conditions, you were to simultaneously touch something connected to your electrical system's 'earth' (e.g. kettle) and 'true earth', you could potentially receive a serious, potentially fatal, shock.

So long as there is nothing at 'true earth potential' within your house, there is no hazard, but a hazard does arise if anything metal enters the building which is, or may be, in contact with 'true earth' outside of the house. The 'Bonding' we are talking about connects any such metal entering the house to the house's electrical system 'earth' - and, in that way, ensures that there can never be a dangerous voltage difference between the two.

A bit complicated, but I hope that has helped a bit?

Kind Regards, John

 

[clifford1]

So long as there is nothing at 'true earth potential' within your house, there is no hazard,

The stone floor ? And all metal appliances etc standing directly on it, like the range cooker, gas cooker, iron bath?

 

[JohnW2]

So long as there is nothing at 'true earth potential' within your house, there is no hazard,

The stone floor ? And all metal appliances etc standing directly on it, like the range cooker, gas cooker, iron bath?

You are unfortuantely creeping progressively further into areas which are technically difficult and the subject of much debate. A dry stone floor should be no problem (poor conductor of electricity). A very wet one does theoretically present a potential hazard (akin to that of using electricity outdoors) but, without going to some pretty ridiculous extremes (e.g. lifting the floor and installing a bonded metal mesh beneath it), there's really not much one can do about it.

In bureaucratic (rather than underlying safety) terms, there are regulations which explicitly require the 'bonding' of such things as metal pipework which enters a building if that pipework is, or may be, in contact with earth outside of the building - so if such bonding is not present, this will be picked up as a deficiency by anyone 'inspecting' the property.

Kind Regards, John.

 

[clifford1]

Thank you very much indeed.Ii think I'll leave the matter there.