Sealing a consumer unit entry points??

[leebut]

Hello Guys


I'm going to put my Tin hat on and close the curtains so the Regs police can't arrest me for asking this question again, I can only find old threads pre 18th edition so please advise me if I'm missing something


I've just been watching a guy on Youtube doing a board change who's said that to comply with the 18th edition of the Wiring Regulations you must seal ALL entry holes into a consumer unit regardless of them coming through the bottom, top, sides or rear entry with a suitable intumescent mastic to stop the spread of fire into the fabrication of the building!!!


I personally am NOT aware that anything changed in the 18th Edition to say all entry points have to be fire sealed I've been looking online tonight and can only find write ups from "Wiring Matters"

Stating


Sealing of wiring entries
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 - see Figure 6. The intent of the sealing is to ensure 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.


Regulation 421.1.201 Does not mention sealing any apertures in a consumer unit with, grommets, glands or sealant and does not mention that the Metal clad board cannot be fitted to a timber backboard. So why is the IET saying we are to be sealing the holes , personally I've been installing all my boards with cables entering from behind and mounting my boards on the existing wooden backboards using a length of stick on trunking as a framework around the consumer unit.


Am I wrong???

 

[richy3333]

@westward10 apologies. No offence was meant on my part and I have to say I missed Chris's last comments so will never know what pearls of wisdom he had to say North of the boarder we're made of string stuff so I cant imagine he would have been offensive...

 

[MFS Electrical]

It really is out of control they will want us to make it fully air tight and pressure test it before were done

Don’t give them ideas

 

[Spoon]

North of the boarder we're made of string stuff

The Scottish are made of string..... Who knew...
I bet it's that tough string that doesn't break easily..

 

[telectrix]

it only breaks intermittently. like morning break 10.00.dinner break 12.30. smoke breaks on the hour, every hour,

 

[Toneyz]

th

Only if you get it all of the time, and not every so often. or intermittently. Soz Ant in one of those moods, forgive please.

Chris was told we are supposed to be sealing all entry points to the CU according The the wiring regulations by the guy running the course but that’s not what’s in the Regulations hence the post

To be honest a few years ago with a previous NICEIC inspector in the days of plastic C.U's he picked up that one of the lads on the back had knocked out the whole of the knockout and not part and pulled us up regarding the enclosure and this was on a plasterboard dot and dab wall with block behind. In the video there is a cavity.

 

[Toneyz]

it only breaks intermittently. like morning break 10.00.dinner break 12.30. smoke breaks on the hour, every hour,

Are you cutting down then Tel?

 

[Charlie_]

If in doubt just follow the manufacturer’s instructions that come with the consumer units.
All the answers are there, just RTFM.

 

[MFS Electrical]

The Scottish are made of string..... Who knew...
I bet it's that tough string that doesn't break easily..

It’s tough string all right

 

[Simon47]

Box it in using asbestos would probably achieve a better fire rating ?

Actually, plasterboard would probably be better. When subjected to the heat from a fire, the gypsum decomposes and releases water which provides protection. That's why fire rated walls and ceilings might just need to be "double boarded" with standard plasterboard.

I also worked on a building where a metal control board set on fire inside and the heat was intense enough for the wooden partition next to it to spontaneously com-busted, even though the flames did not escape the metal enclosure.

The key question being - how long did it take ? The idea of fire breaks and fire alarms is to merely slow the fire down for long enough for people to get out - in small buildings I believe 30 minutes is considered sufficient. I would imagine that if a panel was that hot, it (and the hot wood near to it) would have given off enough fumes to trigger a properly installed fire alarm long before the wood actually combusted.