The intent of Regulation 421.1.201 is considered to be, as far as is reasonably practicable, to contain any fire within the enclosure or cabinet and to minimise the escape of flames.

The non-combustible enclosure or cabinet must provide a complete envelope (e.g. base, cover, door and any components such as hinges, screws and catches) as necessary to maintain fire containment. All blanks, circuit-breakers and other devices must be contained within the non-combustible enclosure or cabinet.

It is important for the installer to seal all openings into the enclosure or cabinet for cables, conduits, trunking or ducting that remain after the installation of cables.
The intent of the sealing is that, as far as is reasonably practicable, any fire is contained within the enclosure or cabinet and the escape of flames to the surroundings of the cabinet or enclosure or into conduits trunking or ducting is minimised, as intended by Regulation 421.1.201.
Good workmanship and proper materials must be used, and account must be taken of the manufacturer’s relevant instructions, if any.

Who is considering that to be the intent of the regulation? Have they mentioned how long the fire should be contained within the enclosure? What does containing a fire as far as reasonably practicable achieve? Surely it's either going to contain it or not, an enclosure which is fully sealed apart from a little hole which was not 'practicable' isn't going to contain a fire at all.
Are they going to stop fitting any knockouts in the enclosures? Because the usual knockouts will just pop themselves open if there is a fire inside that box!

If that is the 'intent' of the regulation then why the hell haven't the IET printed that in the book? Are we supposed to be mind readers to work out what the regulations were supposed to say regardless of what has been printed in the book?
What an absoloute joke!
 
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Who is considering that to be the intent of the regulation? Have they mentioned how long the fire should be contained within the enclosure? What does containing a fire as far as reasonably practicable achieve? Surely it's either going to contain it or not, an enclosure which is fully sealed apart from a little hole which was not 'practicable' isn't going to contain a fire at all.
Are they going to stop fitting any knockouts in the enclosures? Because the usual knockouts will just pop themselves open if there is a fire inside that box!

If that is the 'intent' of the regulation then why the hell haven't the IET printed that in the book? Are we supposed to be mind readers to work out what the regulations were supposed to say regardless of what has been printed in the book?
What an absoloute joke!

I agree!

The IET Dave , have a read through this link.

http://electrical.----------/wiring-matters/55/-files/consumer-units-pdf.cfm?type=pdf
 
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Haha. Silly though isn't it? It should clarified in the BYB itself.

The thing is a thin steel enclosure won't contain a for for very long, especially once that fire has melted the tails and the resultant arc puts a hole in it.

I am tempted to do a bit of a practical experimentation with setting fire to a steel CU, I'm confident I can compromise the integrity of one with fire in under a minute.
 
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Eeerr, Dave, I don’t think black or thermic powder in the enclosure was quite what they had in mind.



It would be fun, could you film it?
 
Eeerr, Dave, I don’t think black or thermic powder in the enclosure was quite what they had in mind.



It would be fun, could you film it?

Well they've been so vague and non-descript about the whole thing that nobody knows what they have in mind.

Black powder, who said anything about mucking around with kids toys? Allow me to introduce the humble waterfall stick.

[video=youtube;taIeHi3rmUE]https://www.youtube.com/watch?v=taIeHi3rmUE[/video]

Looks pretty doesn't it? they come as a box full of 'sticks' which you attach to a string or whatever then fuse together. We have a box of these with the usual chinese characters for their label, so we lit one to check its duration and make sure there were no little surprises. We had it hanging on the side of an empty oil drum, 30seconds later the sparks subsided and there was a big hole in the side of the oil drum. And if that fails there's always aluminium flash powder :)

I've got an old wylex wooden framed jobby set aside for this experiment if I ever get the time to do it, which I will of course film. I want to get a wylex all bakelite and old metalclad 3036 board too along with a modern plastic board, purely in the interest of science of course!

And this is what happens when you put a lot of waterfall sticks in a metal box and light them.
[video=youtube;xPoZ0g1rBqs]https://www.youtube.com/watch?v=xPoZ0g1rBqs[/video]
 
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Well they've been so vague and non-descript about the whole thing that nobody knows what they have in mind.

Black powder, who said anything about mucking around with kids toys? Allow me to introduce the humble waterfall stick.

[video=youtube;taIeHi3rmUE]https://www.youtube.com/watch?v=taIeHi3rmUE[/video]

Looks pretty doesn't it? they come as a box full of 'sticks' which you attach to a string or whatever then fuse together. We have a box of these with the usual chinese characters for their label, so we lit one to check its duration and make sure there were no little surprises. We had it hanging on the side of an empty oil drum, 30seconds later the sparks subsided and there was a big hole in the side of the oil drum. And if that fails there's always aluminium flash powder :)

I've got an old wylex wooden framed jobby set aside for this experiment if I ever get the time to do it, which I will of course film. I want to get a wylex all bakelite and old metalclad 3036 board too along with a modern plastic board, purely in the interest of science of course!

And this is what happens when you put a lot of waterfall sticks in a metal box and light them.
[video=youtube;xPoZ0g1rBqs]https://www.youtube.com/watch?v=xPoZ0g1rBqs[/video]


Oh!! ... I like that!!

I can think of a few Working Men's Clubs I'd like to give that treatment to!! :devil2:
 
Like catherine wheels they are a good way to fill out the time when a client expects a 20minute display for the price of 10minutes. With the added advantage that unlike catherine wheels you don't have to hit them with a stick to make them spin round (yes even us pro's have to get up to those tricks)
 
interesting reading so do we agree or not if cables are rear entry we apply fire barrier or fire paste its only a question that i think all us sparks need to no before we start installing these new consumer units. personally come the day i install these new boards ie january 2016 im going to adhere to 421.1.201 and apply fire paste (barrier)
 
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interesting reading so do we agree or not if cables are rear entry we apply fire barrier or fire paste its only a question that i think all us sparks need to no before we start installing these new consumer units. personally come the day i install these new boards ie january 2016 im going to adhere to 421.1.201 and apply fire paste (barrier)

I'm looking forward to seeing an attempt to fill entries in busy DB's,especially rear entries once a DB is fully installed. If you consider the practicallities it will be very difficult to properly fill entries once a DB is finished,which leaves the option of getting cables into the DB,filling holes,and then waiting for filler to harden before connecting to avoid disturbing the sealant.
"Yes missus,I'll strip out the old DB and fill on the first day,and then leave you with no power all night while the sealants hardening,and then connect and test next day....that ok?"
 
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interesting reading so do we agree or not if cables are rear entry we apply fire barrier or fire paste its only a question that i think all us sparks need to no before we start installing these new consumer units. personally come the day i install these new boards ie january 2016 im going to adhere to 421.1.201 and apply fire paste (barrier)

I agree. At the end of the day if you are part of a scheme/scam and you showed them a job where you haven't even attempted to then it will be classed as a non conformance (it's only a £3 tube of sealant). I know there will be other sparks on here who think you should argue with your scheme accessor until your blue in the face about the do's and don'ts but after all I want to just get him in and out as quick as possible with no dramas.
 
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Mean while, in millions of factories, shops, warehouses etc there are platic DBs being installed which will comply with the BYB.
 
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I agree. At the end of the day if you are part of a scheme/scam and you showed them a job where you haven't even attempted to then it will be classed as a non conformance (it's only a £3 tube of sealant). I know there will be other sparks on here who think you should argue with your scheme accessor until your blue in the face about the do's and don'ts but after all I want to just get him in and out as quick as possible with no dramas.

I can understand your point that you want 'it' out of the way.
But, if someone is wrong, they need challenging; rolling over just perpetuates the crapness.
 
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