The Future of Fuse boards...?

[Dustydazzler]

Looks nice

 

[westward10]

If that is an IET link it won't work here. Show where that Regulation infers what you suggest.

 

[mainline]

The IET site say's
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.

Take it up with them, I'm just stating what they say.

 

[Midwest]

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.


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.

You've appear to have copied & paste some lines in your reply. If you could citations. Edit IET.

I'm no longer up to date on BS7671, so I'll tilt my hat to you.

If you going to spend time and money 'to seal all openings', what are you going to do with the big flap on the front of a consumer unit, that covers all the inner workings of said CU? Seems little pointless 'sealing' everything, when this is flawed by the CU cover?

 

[nicebutdim]

Metal box, with restricted air inlet, opening into a vertical cavity is a definition of both the CU in the OP, and the wood burner beside me, that my wife has just lit.

DBs aren't intended for lighting fires in.

The same argument could be applied to kitchens fitted with an extractor fan and trickle window vent and the likelihood of fires starting in a kitchen are considerably higher, than one starting in a DB installed in line with regulatory requirements.

 

[mainline]

You've appear to have copied & paste some lines in your reply. If you could citations. Edit IET.

I'm no longer up to date on BS7671, so I'll tilt my hat to you.

If you going to spend time and money 'to seal all openings', what are you going to do with the big flap on the front of a consumer unit, that covers all the inner workings of said CU? Seems little pointless 'sealing' everything, when this is flawed by the CU cover?

The debate is over whether to leave an oversized hole in the rear of a CU that goes into a wooden partition.

 

[nicebutdim]

The debate is over whether to leave an oversized hole in the rear of a CU that goes into a wooden partition.

You stated in post #11 that this involved a partition.

The reality is that it's a studio set and we don't know what they intended it to represent. I'm going with the previous suggestion of it representing a board spaced off a wall with battens, because I like that idea.

 

[brianmoooore]

DBs aren't intended for lighting fires in.

The same argument could be applied to kitchens fitted with an extractor fan and trickle window vent and the likelihood of fires starting in a kitchen are considerably higher, than one starting in a DB installed in line with regulatory requirements.

No one intends to light a fire in a DB, but we all know that they manage to do this themselves, usually when one of the poorly designed connections isn't assembled properly.
Don't think a wall mounted extractor in a kitchen is going to fan a kitchen fire to any significant degree, and there's a minimum distance between a hob and and extractor over it for just that reason.

 

[nicebutdim]

No one intends to light a fire in a DB, but we all know that they manage to do this themselves, usually when one of the poorly designed connections isn't assembled properly.
Don't think a wall mounted extractor in a kitchen is going to fan a kitchen fire to any significant degree, and there's a minimum distance between a hob and and extractor over it for just that reason.

My point was that a cored extractor, combined with trickle vent, provides an ideal means of fanning a fire.

How many fires start in DBs each year and how many start in kitchens?

I also note that no one arguing against rear knockouts has adressed my point about whether or not they insist on homes having interlinked smoke/fire detection as a prerequisite to board changes.

 

[mainline]

You stated in post #11 that this involved a partition.

The reality is that it's a studio set and we don't know what they intended it to represent. I'm going with the previous suggestion of it representing a board spaced off a wall with battens, because I like that idea.

And I'm going with a stud wall partition.

 

[westward10]

Metal consumer units are suggested as they do not readily promote the spread of fire, they will not contain it so in my opinion the IET are misrepresenting the intention of the Regulation. Cable entries do not require fire stopping unless the rear entry breeches a fire compartment and this is possible if the reverse side of the cavity wall is also breeched for example by an accessory cavity back box.

 

[westward10]

My point was that a cored extractor, combined with trickle vent, provides an ideal means of fanning a fire.

How many fires start in DBs each year and how many start in kitchens?

I also note that no one arguing against rear knockouts has adressed my point about whether or not they insist on homes having interlinked smoke/fire detection as a prerequisite to board changes.

It is a good point about extraction fans, how do we fire seal the hole made for them because if they breech a fire compartment you have problems. We fit fire rated down lights but ignore the extractor which has made an even bigger hole in the ceiling if that is where it is fitted.

 

[brianmoooore]

whether or not they insist on homes having interlinked smoke/fire detection as a prerequisite to board changes.

I insist on interlinked mains power smoke alarms, with battery back up, on any domestic property I've done extensive work on, whether the customer asks for or even wants them. If they refuse, then they find another sparky.

 

[brianmoooore]

It is a good point about extraction fans, how do we fire seal the hole made for them because if they breech a fire compartment you have problems. We fit fire rated down lights but ignore the extractor which has made an even bigger hole in the ceiling if that is where it is fitted.

Most ceiling extractors are in shower and bath rooms, which aren't exactly hotspots of domestic fires, but if you do breach a fire compartment with fan ducting, then it should be fitted with an intumescent fire sleeve.

 

[mainline]

Metal consumer units are suggested as they do not readily promote the spread of fire, they will not contain it so in my opinion the IET are misrepresenting the intention of the Regulation. Cable entries do not require fire stopping unless the rear entry breeches a fire compartment and this is possible if the reverse side of the cavity wall is also breeched for example by an accessory cavity back box.

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.

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 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




Your opinion obviously differs from the IET who are involved in actually writing the regs to which you quote.

 

[Dave OCD]

I insist on interlinked mains power smoke alarms, with battery back up, on any domestic property I've done extensive work on, whether the customer asks for or even wants them. If they refuse, then they find another sparky.

Are you worried your work is going to catch fire Brian ?