This has to be against building Regs???

Bruthal

sinnerboy wrote: »

My own unfortunate experience of a bathroom leak is that water builds up on top of the plasterboard up to 50mm deep ! It finds the weak spot - your light fitting. Imagine going for you cornflakes to find your light fitting is raining!

If you ever find this happen to you then use a screwdriver or similar to puncture holes and "drain" your floor before it eventually collapses in a soggy mess.

There was no damage to any of my electrics afterwards btw.

Yea I had it myself here from the ensuite above the kitchen. Down through the kitchen light. It was handy, i was able to make the hole in the ceiling above the sink:)

OP - with respect the scene you are imaging is straight out of one of the "Final Destination" franchise of movies. There is no regulation breach and you are not in danger.

Yea, not much danger of electrical shock even of the plug hole disappeared and the water flowed straight into the DB, there would be little shock danger to anyone in the bath.

Dardania

OP, as an electrical engineer, I don't reckon that your situation is against building regulations. However, if you believe it to be, a handy way to check is to look at the Technical Guidance Documents to compkly with building regulations - see: http://www.environ.ie/en/TGD/. Bear in mind that those docs are not retrospective, your building would have to comply with the regulations in force when the house was built...

I noticed that much of the regulations regarding siting of electrical equipment is covered in the ETCI regulations as the other posters note.

Bruthal

spankmemunkey wrote: »

Why is it that if your in a bath and a hair dryer is thrown in with you your dead yet if your lying in a bath and it leaks onto a board below you should be fine???? why arent light switches allowed in a bathroom? why is the IP rating of a light fitting in bathroom different? why all these rules and then oh okay you can physically fit a fuse board close than you can a light switch??

If a hair dryer is thrown into a bath, its not certain to be fatal.

Also, that is far different from water dribbling onto a fuseboard sell outside the bath. Why are we not killed when it rains with 110,000 volt overhead lines nearby?

Water is a poor conductor, but it decreases the skin contact resistance. It has a large area (finger tips in mm2) and extremely short conductor length (fraction of mm) when wet hands are touching a live point, and so severe shocks result from that if there are at least 2 points of 230v potential difference contact.

From the bath to the fuseboard, it would be a very long conductor length (2 or 3 feet likely at minimum) that the water forms, which would have very poor conduction up to the bath, and very narrow conductor width. There simply would not be any shock danger inside the bath with that.

Switches in bathrooms are not allowed due to the very close proximity of live contacts with the gaps in the switch rockers, but even if they were allowed, electrocution would be unlikely especially with latest regs. They allow sockets and switches in bathrooms in other countries without much problem.

I got small shocks on a farm from absolutely drenched switches once or twice, no real danger of being electrocuted from that. I would think if some had touched the same switch, they would have thought they had been blown across the outhouse, and barely survived, mainly from the terror and then losing their balance as they jump with fright.

So all in all, no danger of electrocution in the bath from a DB in the room below, no matter how the bath leaks.

sydthebeat

spankmemunkey wrote: »

Its not about electrics its about planning and the positioning of a bath!!!! dont see why you moved it!

its quite obviously about electrics and NOTHING to do with planning issues.

Its also nothing to do with the location of the bath... the location is usually designed at initial design stage.
the *specific* location of the MCB however is down to the electrician and common sense would dictate not to have it located directly under a bath U bend.

However you have been told by members on here that its not against regulations.
My own homework also tells me that there are no regulation breach in this.

2011

spankmemunkey wrote: »

Why is it that if your in a bath and a hair dryer is thrown in with you your dead

Because it makes good TV. Although I would not recommend it the chances of being injured or killed are remote.

yet if your lying in a bath and it leaks onto a board below you should be fine????

Ditto

why arent light switches allowed in a bathroom? why is the IP rating of a light fitting in bathroom different?

Because with wet hands there is an unacceptable risk of shock. This is not the case with a board located under a bath. With the light switch the best path to earth is more likely to be through a person. With the board it is much more likely to be through the multiple neutral and / or earth conductors.

Bruthal

2011 wrote: »

Because it makes good TV. Although I would not recommend it the chances of being injured or killed are remote.

Its an interesting one that, I might leave that one off my list of experiments though...

brightspark

spankmemunkey wrote: »

Why is it that if your in a bath and a hair dryer is thrown in with you your dead yet if your lying in a bath and it leaks onto a board below you should be fine???? why arent light switches allowed in a bathroom? why is the IP rating of a light fitting in bathroom different? .

Because electricity likes to find the shortest path.

hair dryer in bath and the shortest path is possibly through you.

if the board gets wet the shortest path is going to be within the board. it certainly won't be up to the bath through the occupant and back down again!

switches are not allowed because if they were wet the shortest path could be through the wet finger, down the arm, pdf past the heart, down through wet feet!

higher ip rating is mainly due to the steamy conditions and to prevent accidental contact. Also an unprotected lamp can shatter if wet and then turned on.

Another point to consider is that water doesn't always leak straight down, but often follows joists etc. so there is no certainty that any leak upstairs won't find it's way to wherever the board is located.

Bruthal

brightspark wrote: »

switches are not allowed because if they were wet the shortest path could be through the wet finger, down the arm, pdf past the heart, down through wet feet!.

Electrocution would be still be very unlikely though, via a wet switch.

brightspark

robbie7730 wrote: »

Electrocution would be still be very unlikely though, via a wet switch.

Yes, I agree it would be very unlikely, but perhaps if someone had a weak heart, very wet feet and hands, and managed to still hold the switch while being shocked, it might just happen.

spankmemunkey

Okay everybody thanks for your replys! I think i can just leave it now, I still think that its not a great positioning of a fuse board under a bath, I think it would have been better to have placed the board the other side of the hall, you all have to admit that leaking water onto a board still isnt recommended but thanks again for your opinions, I have to say the guy in RECI told me he wouldnt sign off on it, even though its not against regulations he did say external influences should have been considered, he did also say that if water go onto the board the main fuse should blow or the RCD trip.

muffler

spankmemunkey wrote: »

he did also say that if water go onto the board the main fuse should blow or the RCD trip.

There ya go

2011

spankmemunkey wrote: »

I think i can just leave it now, I still think that its not a great positioning of a fuse board under a bath, I think it would have been better to have placed the board the other side of the hall,

Agreed, another location would have been preferable. However this does not mean that it is against any rules or regulations, consequently if you want it moved it will mean paying someone to move it.

you all have to admit that leaking water onto a board still isnt recommended

Water & electricity are traditionally a bad mix, there is no denying that.

I have to say the guy in RECI told me he wouldnt sign off on it

My experience with RECI inspectors has been very negative, so I would take that with a large pinch of salt. I found it impossible to get them to take any action when they admitted that important ETCI regulations were broken and in my opinion "bad practice" was employed.

even though its not against regulations he did say external influences should have been considered

Which is absolutely correct. For all we know the board was installed first, and then the bath was an after thought. You may also find that the board location may have been selected by the architect and the electrical contractor was simply installing it where it was marked on the drawing without even knowing that a bath was to be installed above it.

M cebee

spankmemunkey wrote: »

Okay everybody thanks for your replys! I think i can just leave it now, I still think that its not a great positioning of a fuse board under a bath, I think it would have been better to have placed the board the other side of the hall, you all have to admit that leaking water onto a board still isnt recommended but thanks again for your opinions, I have to say the guy in RECI told me he wouldnt sign off on it, even though its not against regulations he did say external influences should have been considered, he did also say that if water go onto the board the main fuse should blow or the RCD trip.

the 2 general rules cover:
- protection against adverse 'environmental condtions' dust,moisture etc.
to me that means the environment in the room in which board is located

the other rule relates to damage from faults in other services.
-can you say that leaking wastes or badly fitted bath trim and the like are faults in other services?

2011

M cebee wrote: »

-can you say that leaking wastes or badly fitted bath trim and the like are faults in other services?

I think that could only be argued if you could demonstrate that there was a high probability of a leak.
How high a probability, how long is apiece of string?
Very subjective.

Bruthal

brightspark wrote: »

Yes, I agree it would be very unlikely, but perhaps if someone had a weak heart, very wet feet and hands, and managed to still hold the switch while being shocked, it might just happen.

There is still a danger, and that is, people who get mild shocks often jump with fear, fall etc, and this is multiple times more dangerous than the shock that might be received from a switch itself in a bathroom.

You can read stories (there was a thread on boards recently about it)of people who touched both pins of lamp holder with a finger while standing on a bed etc, claim they were thrown across the room, something not realistic in that scenario from the actual electric shock.

james142

After reading this post I have just realised that my fuse box is directly under my bath tub too :eek:

spankmemunkey

2011 wrote: »

I think that could only be argued if you could demonstrate that there was a high probability of a leak.
How high a probability, how long is apiece of string?
Very subjective.

Think about it, when you fill a bath with water your increasing pressue on a fibreglass structure, then you get into it adding more weight, I have had experience of baths leaking, my mothers bath leaks where the bath sits on its feet theres like two holders under it, the bath moves after years of getting in and out and it now leaks ever so slightly, theres also a chance of water getting behind the bath on the cascading wall if your having a shower. and dont forget the bad quality of materials used during the property boom,

I didnt get a second reply from my county council when i suggested that it wasnt the electrical rules that were broken rather the planning position of the bath i asked was the council not envolved in signing off on these plans i didnt get a reply!

Bruthal

spankmemunkey wrote: »

Think about it, when you fill a bath with water your increasing pressue on a fibreglass structure, then you get into it adding more weight, I have had experience of baths leaking, my mothers bath leaks where the bath sits on its feet theres like two holders under it, the bath moves after years of getting in and out and it now leaks ever so slightly, theres also a chance of water getting behind the bath on the cascading wall if your having a shower. and dont forget the bad quality of materials used during the property boom,

I didnt get a second reply from my county council when i suggested that it wasnt the electrical rules that were broken rather the planning position of the bath i asked was the council not envolved in signing off on these plans i didnt get a reply!

So you still believe a person in the bath can be electrocuted from water leaking from it to the DB in a room below?

spankmemunkey

robbie7730 wrote: »

So you still believe a person in the bath can be electrocuted from water leaking from it to the DB in a room below?

Im not convinced but ill have to take your word for it, and there is recordings of people dying in the bath with a hair dryer for the other poster who says its not gonna happen.
Anyway im not fond of the idea of taking a bath showers only in the other room

Bruthal

spankmemunkey wrote: »

Im not convinced but ill have to take your word for it, and there is recordings of people dying in the bath with a hair dryer for the other poster who says its not gonna happen.
Anyway im not fond of the idea of taking a bath showers only in the other room

I agree with the other poster about the hair dryer. But the fact is, a hair dryer within the bath, is not going to be even remotely like a leak down to the mcb board.

But besides that, you best remove the light fittings below as well, as the water is far more likely to build up around that, than make a continuous conductor to the mcb board.

I had that happen in my house (light fitting below ensuite shower), and neighbour as well. We both survived no problem. I had to make holes in ceiling to release water, and in neighbours case, the light fitting was drenched when I removed it.

How many have you heard of, electrocuted in a bath here through leaking water? I doubt your setup is unique.

What about when immersion elements fail? Live elements often straight into the water. How many were electrocuted from that? They trip these days due to having RCD`s on them, the same as a hair dryer into bath likely would if any current flowed into the water/person, and to earth. But years ago they stayed on.

There is a lot of myth around electrical stuff, and this leak from a bath into a board below, or light fitting, and electrocuting someone in the bath, is a new one on me, most likely something for a final destination film as someone else suggested I think.

2011

spankmemunkey wrote: »

Think about it, when you fill a bath with water your increasing pressue on a fibreglass structure, then you get into it adding more weight, I have had experience of baths leaking

Yes, it it is possible that a bath may leak on to your distribution board and clearly water and electricity are not a good mix.
However, I do not believe that any electrical regulations have been broken due to the location of the distribution board and I would like to think that I am quite familiar with these regulations.

Although I never studied that building regulations I have worked in the construction industry for many years, so I have an appreciation of what is and is not permitted. I do not think that the position of the distribution board in relation to the bath contravenes any of these regulations.

I agree that this is not the ideal location for the board. I would have located it elsewhere, but I believe that it is not breaking any regulations.

Of course wires run under floor boards but they dont pose a direct risk of death as it does when your sitting in a bath and it leaks onto the fuse board a few inches below you.

In simple terms:
Electric current moves from a higher potential (in this case 230VAC) to a lower potential (in this case 0V or earth potential). This current will always take the path of least resistance to flow from mains voltage to earth. It is when this path is through you that you receive an electric shock as illustrated in the picture below.

Your scenario (you in bath, bath leaks on board) the chances of the path of least resistance being through you is extremely remote in my opinion. I would expect the water to cause a short to occur within the distribution board. This should cause one or more devices to trip or blow in a very undramatic way (bit of an anti-climax really).

Electricity also arcs!

Thank God it does! If it didn't many of the great inventions that we take for granted would not work such as spark plugs and electric arc welders :D:D

Bruthal

The fundamentals of what actually would happen in the bath leaking scenario, are clouded by the inherent assumption that water must conduct well enough to cause electric shock when water leaking from a bath comes in contact with a live terminal several feet outside the bath.


The resistivity of tap water is given as between 20 and 2000 ohms/meter.

Thats a cubic meter of water with contacts on 2 opposite 1 square meter faces, in contact with the entire meter square surface on each side.

If we take the lowest given 20 ohms, and 1 square cm of water (1/10.000th of square meter), and 1 meter long, this would amount to 200,000 ohms resistance. Even if we take 10cm square, that is still 20,000 ohms, and 10cm square is as big as the bath plughole.

A 1 square cm square column of water can not possibly connect from the live terminals of an MCB board and up into the bath if we take it as at least 3 feet away. It will be a much thinner water path than that, in the extremely unlikely event there was even a continuous water route from bath to live terminal at all. But even if it did, 200,000 ohms is far too high a resistance to have any affect on anything in the bath.

Like I said before, wet finger tips touching live parts, have a water conductor length of very small fractions of mm (water between finger tips and point they are touching), but area of multiple square mm`s, causing far more severe shocks than dry hands receive. The water eliminates the skin resistance we have. Salt from the skin makes the water even better a conductor.

spankmemunkey

Okay guys thanks for all the replys!

Bruthal

If water was a good conductor, it would short this hair dryer. It seems to intermittently trip RCD, and do little else to it.