Shower Electrocution in France

Who would be stupid enough to leave live parts beside their child's bed? I left the power on to a bed side lamp and removed a blown bulb intending to replace it. I was distracted and forgot to do that. My daughter was only around five at the time but she knew how to switch the lamp on at a point near the base of the lamp holder. Little exploring fingers made contact with the live pins in the holder. Luckily only slight burn injury. I am sure that I am not the only one to have been so unintentionally careless. We make a big deal out of blanking components missing from an industrial distribution board yet seem to turn a blind eye to the obvious danger with plug-in lamps.

Interestingly, over the years I have spoken to several  folk who have either had a belt from a lamp holder or know someone who has, so  I think it is quite a common childhood shock mechanism, this encompasses folk who are now well and truly retired, and some young children, so the UK lampholder has been biting people for probably a century or so (*).

But equally I don't know of anyone being killed by it, which I guess is something. The contact area is limited and it is likely to be a finger to finger shock, at least in a dry location like a bedroom with no large bath tub to stand in. I'm not saying it's a good thing mind you, just that both in theory, and seemingly in practice, it is a relatively survivable  event.

There are lampholder designs that only liven up the pins once the lamp is in postion, though the only ones I have seen have been pretty badly made. Ideally, perhaps  that should have been incorporated into the standards when the shuttered sockets and sleeved pins came in for plugs, at least for table lamps, and no-one would question it by now, but that horse has rather bolted. 

I suspect there will be no further change to the UK lampholder BS until eventually it falls into disuse in favour of things with LEDs and no bulb as such to replace, which will probably be many years in the future. (some of the lamp holders in my house are certainly  originals from about the late 1960s to 1970, and I supect they are not alone. )



* EDIT More like 130 years then; Though this text book from 1885 shows an early design of  bayonet lampholder with a little circular cover disk to protect the contacts when no lamp is inserted. So clearly that got optimsed away when the bayonet fixing design went into mass  production.

https://archive.org/details/electricillumina02dred/page/n341

Interestingly, over the years I have spoken to several  folk who have either had a belt from a lamp holder or know someone who has, so  I think it is quite a common childhood shock mechanism

Yes, you can add me to that list too. In my younger days the indoor Christmas tree lights (for reasons I've yet to fathom) seemed to be wired into a BC plug - and if there wasn't a handy lampholder near to the tree, a length of flex with a plug on one end and a BC lampholder on the other was used. Twiddling with the empty lampholder while waiting for some detail of the tree decoration to be sorted out...  Mind you I did seem to have a predisposition for getting shocks at that age, there was the 'I wonder if the element of the radiant electric fire gets hot after it's switched on but before it glows' experiment (the guards in those days weren't quite fingerproof for small fingers...)


  - Andy.

How did any of us survive? ?


My first belt was at the age of about 8. There was a bed light, which was clipped to the headboard, and which had a switch dangling from the end of a bit of cable. The alarm went off, I reached up to turn on lamp, but the switch had fallen off in the night, so I grabbed the live cable. By God, I have never before or since jumped out of bed so quickly! ?


As far as BC lamp holders are concerned, MK make "shockguard" batten and pendant lampholders, but they do require quite a lot of torque to insert a lamp - it makes me worry that the globe will break off the metal bit. However, we must all be familiar with the usual BC lampholders on table and standard lamps which are screwed on to a ferrule, but which undo when one attempts to remove the lamp. Time for a redesign?

I went to a property on a call out. Switching the bedroom light on was tripping the MCB. Then came the confession. One of the customer kids had lent over from his bunk bed and placed a 5 pence piece across the pins on the pendant. The coin was welded in place. The child didn't get a shock.

I've been lucky, only had about 6 electric shocks and several tingles, no 3-phase belts, no HV close encounters in 50 odd years but not without  several 3036 fuse wire/lead cable fast melt experiences. I think the saving grace is insulation to other phases/earth. As an Electrician you cannot 'insulate' yourself from contact with live electrical terminals/conductors and survive without insulation because you are invariably in 'contact' with it all the time.

This doesn't apply to non electrically competent persons who are more likely to put themselves into harms way without realizing or indeed understanding what has happened before its too late.

Instantaneous electric showers are more dangerous than most domestic heating appliances primarily because the insulation between you and the electricity supply is at a minimum when immersed in water with no clothes on.

We tend not to bath in water heated by electrodes, for obvious reasons,  but there are cases where non-insulated heating elements are used to supply heated water. This is another potentially dangerous method of heating which is quite common in foreign countries, and I expect this was the rascal that caught our French chap..

So it appears our only protection when showering in an earth fault condition is a fast reacting RCD, unless you wearing your Hunter wellies and Marigold gloves,gaffer taped up,  in the shower room or indeed the the bath tub !


Legh

Standing in a metal bath whilst using an electrical shower may be a little dangerous, it depends upon the bath being earthed, but if the bath is glazed and insulated from its base metal the earth path is reduced or removed. Just how conducting to earth is it? And plastic water pipes may insulate the bath even more. The bath may even electrically float.


Modern electric showers located within a shower cubicle or over a glass fibre (G.R.P.) bath tub pose little risk if the plastic cover is intact and R.C.D. protection is present. A shower tray may be porcelain or glass fibre, the pipes may be plastic, the cubicle walls may be glass, all non conducting and earth free. So the earth path is removed.


Z.