Running 6mm twin & earth cable.

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Aside from being an electrician I also work in fire safety and whilst buildings have defined escape routes it has been argued that almost anywhere in a building could be included as an escape route, defined or not. If you are in a toilet, kitchen or anywhere and an evacuation situation occurs then the footfall from your location can be deemed your escape path. 


Dead end rooms such as toilets and bedrooms are not escape routes, they are places to escape from. How long are you likely to be in such a room with a fire? 

 
They are not defined escape routes but if as you say they are places to escape from they therefore create part of your escape route. The duration in which you occupy the space isn't relevant I was just pointing out that there is more to escape routes than those which are defined as such.

 
They are not defined escape routes but if as you say they are places to escape from they therefore create part of your escape route. The duration in which you occupy the space isn't relevant I was just pointing out that there is more to escape routes than those which are defined as such.


So...   if  "Duration" is not relevant...

How do we know how long is long enough when evaluating if something will fail "Prematurely"...????   :C

i.e.  Premature: Occurring, growing, or existing before the customary, correct, or assigned time; uncommonly or unexpectedly early:


Perhaps you could enlighten us with your wisdom as to exactly what is the measure of "premature failing" that you consider 521.10.202 refers..

Should our cables remain fixed if all other structures on a wall have been consumed by fire..?

Should our cables still be fixed if the roof has collapsed...? 

Should our cables be the last things standing after a property has been raised to the ground..?

Should our cable fixings outlast other "fire barriers"..?

Should our fixings exceed the expected times for people to evacuate a building, (e.g. ref emergency lighting durations)..?

etc..

etc..?

Getting back to fundamental principles, 131...  when designing, installing & testing electrical installations.. 

the bottom line is  ensure it fails-safe and protects People, Property & Livestock...

IMHO premature failing of cables fixed to walls isn't going to be protecting a property very much...?

As the fire is already raging through the timbers, etc..

But rather protecting people & livestock....   

who 99% of the time will be looking at escape routes and the evacuation times needed to use that route..

and/or emergency services who may need to access a property with known persons still trapped...

But the average single entrance domestic garage..  (to which this thread refers)...

would need one-helluva big fire to see even bog standard plastic cable clips melt from the wall before someone can walk a few meters to get out!!

And the average emergency service person will soon figure if they really need to enter the said garage..

where our cables are still probably causing little or no obstruction..

compared to the old sofa, kids bikes, black & decker workmate, freezer, golf clubs, half roll of carpet off cuts, part used paint tins, lawn mower, dads tool box,  etc.. etc..

The question the OP was asking about is a bit of 6.0mm in a garage..

NOT a whole bunch of cables plastic strapped on the underside of some cable tray across a 300m long warehouse!

:shakehead

:popcorn

 
Aside from being an electrician I also work in fire safety and whilst buildings have defined escape routes it has been argued that almost anywhere in a building could be included as an escape route, defined or not. If you are in a toilet, kitchen or anywhere and an evacuation situation occurs then the footfall from your location can be deemed your escape path. 
a toilet, kitchen or anywhere are unlikely to be an escape route

i do think some people go out of their way to complicate matters/ or should I say create paid work for themselves

 
They are not defined escape routes but if as you say they are places to escape from they therefore create part of your escape route.


 They aren't defined as escape routes becuase they aren't escape routes. We protect the actual escape routes so that having exited a dead end room, people have a safe egress route and firemen have a safe route to access the fire within the building. 

 
i do think some people go out of their way to complicate matters/ or should I say create paid work for themselves


the phrase you are looking for is 'frightened little children' ie those who are so scared of getting things wrong, they make everyone elses life miserable with rediculous interepretation of rules and regs

 
So...   if  "Duration" is not relevant...

How do we know how long is long enough when evaluating if something will fail "Prematurely"...????   :C

Perhaps you could enlighten us with your wisdom as to exactly what is the measure of "premature failing" that you consider 521.10.202 refers..

Should our cables remain fixed if all other structures on a wall have been consumed by fire..?

Should our cables still be fixed if the roof has collapsed...? 

Should our cables be the last things standing after a property has been raised to the ground..?

Should our cable fixings outlast other "fire barriers"..?

Should our fixings exceed the expected times for people to evacuate a building, (e.g. ref emergency lighting durations)..?

etc..

etc..?

Getting back to fundamental principles, 131...  when designing, installing & testing electrical installations.. 

the bottom line is  ensure it fails-safe and protects People, Property & Livestock...

IMHO premature failing of cables fixed to walls isn't going to be protecting a property very much...?

As the fire is already raging through the timbers, etc..

But rather protecting people & livestock....   

who 99% of the time will be looking at escape routes and the evacuation times needed to use that route..

and/or emergency services who may need to access a property with known persons still trapped...

But the average single entrance domestic garage..  (to which this thread refers)...

would need one-helluva big fire to see even bog standard plastic cable clips melt from the wall before someone can walk a few meters to get out!!

And the average emergency service person will soon figure if they really need to enter the said garage..

where our cables are still probably causing little or no obstruction..

compared to the old sofa, kids bikes, black & decker workmate, freezer, golf clubs, half roll of carpet off cuts, part used paint tins, lawn mower, dads tool box,  etc.. etc..

The question the OP was asking about is a bit of 6.0mm in a garage..

NOT a whole bunch of cables plastic strapped on the underside of some cable tray across a 300m long warehouse!

:shakehead

:popcorn
I was referring to what can be considered an escape route. In terms of fire safety you have defined escape routes and routes of passage leading to the defined routes this is likely to encompass most of the floor space. The space of time a person occupies this space is not a concern as it does not change the fact of whether it is or is not a route of escape. My comment was not referring to the length of time that cable support will collapse.

 
Fixings will need to be as such that the cable will not prematurely collapse in the event of a fire.


I was referring to what can be considered an escape route. In terms of fire safety you have defined escape routes and routes of passage leading to the defined routes this is likely to encompass most of the floor space. The space of time a person occupies this space is not a concern as it does not change the fact of whether it is or is not a route of escape. My comment was not referring to the length of time that cable support will collapse.


May I suggest you don't actual remember what you have already posted...

have a quick  re-read of the third post on this thread...

your first comment..   (I've copied it above for you..)

Which is how you also brought around the discussion of escape routes etc...

as you have been have been the one quoting interpretations of 521.10.202 -vs- 521.11.201,

So will you know please answer my question..?

Can you enlighten us with your wisdom as to exactly what is the measure of "premature failing" that you consider 521.10.202 refers..

Should our cables remain fixed if all other structures on a wall have been consumed by fire..?

Should our cables still be fixed if the roof has collapsed...? 

Should our cables be the last things standing after a property has been raised to the ground..?

Should our cable fixings outlast other "fire barriers"..?

Should our fixings exceed the expected times for people to evacuate a building, (e.g. ref emergency lighting durations)..?

etc..

Please note we are referring to PVC 6.0mm T&E, 

which is a commonly used circuit cable in many domestic situations. which are often run though domestic single entrance garages..

Which is what the original question was enquiring about..

Or are you unable to offer an actual real world interpretation of how these regs are applied...     to a real genuine question..

Rather than just arguing meanings and interpretations..    without any actual examples of implementation..?

How soon is premature in your interpretation?

:C

 
the phrase you are looking for is 'frightened little children' ie those who are so scared of getting things wrong, they make everyone elses life miserable with rediculous interepretation of rules and regs
I think it’s simply a problem endemic in the UK where something that should be written as black or white is written in some odd grey colour and open to interpretation. 
 

The DCLG are very guilty of this 

 
Yes I remember what I posted I was later considering an escape route being more complicated that just the defined escape routes which may or may not have bought about the Regulation change. The duration for premature collapse will be variable whereby a BD4 route may require 2 hours before premature collapse takes place.

 
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Yes I remember what I posted I was later considering an escape route being more complicated that just the defined escape routes which may or may not have bought about the Regulation change. The duration for premature collapse will be variable whereby a BD4 route may require 2 hours before premature collapse takes place.


Which confirms once again it is mostly irrelevant waffle you state in context the the OP's question...

i.e. in relation to  a bit of 6.0mm through a single entry domestic garage....   :shakehead

Its not rocket science to figure out what and where any escape routes are....

how many persons would typically be living, sleeping, occupying or doing other tasks within the garage..

and/or what will or won't fail prematurely, presenting any risk of danger to any persons..

So lets try again...  from your initial post...

"Fixings will need to be as such that the cable will not prematurely collapse in the event of a fire."

How soon is too soon for premature collapse in a single entry domestic garage..

that makes you even raise the point back on post 3?

( Note: there is little point waffling about BD4 routes...   as most of us are well aware of things like..

BD2 – Low density occupation, difficult conditions of evacuation

BD3 – High density occupation, easy conditions of evacuation

BD4 – High density occupation, difficult conditions of evacuation

etc..  etc..   blah..  blah..  blah..  )

Now I don't know of many single entry domestic garages that are..   

"High density occupation, difficult conditions of evacuation"

I would suggest  that 2hrs is a bit of an irrelevant duration in this instance...  :C ?

So lets not overcomplicate a simple question..

How long do you think this bit of 6.0mm needs to stay clipped to the garage wall..

that also made you bring up 521.10.202?

:coffee    

 
I don't believe I suggested the garage was BD4 I just gave a generic example apologies if this confused. Considering fire rated clips are generally tested at 930°C for two hours although this may vary between manufacturers so the use of over the counter clips is likely to give a two hour duration.

 
I don't believe I suggested the garage was BD4 I just gave a generic example apologies if this confused. Considering fire rated clips are generally tested at 930°C for two hours although this may vary between manufacturers so the use of over the counter clips is likely to give a two hour duration.


 but does a single entry garage need 2 hours? I would suggest the whole house would have burnt down by then  :^O

 
I think it’s simply a problem endemic in the UK where something that should be written as black or white is written in some odd grey colour and open to interpretation. 
 

The DCLG are very guilty of this 


More a case of 'catch all' circumstances perhaps?  Now, it has to be said that writing regs to cover every situation is plain damn hard, so leaving grey areas is easier than writing things in black and white and letting people interpret / apply common sense.  If you write in B&W and possibly miss a circumstance that leads to a failure / death, you risk being sued. So we are also suffering an increasingly 'risk adverse' society, ie no risk (to the author) is better than writing something that could be wrong. Prime example, the story of the lady who killed her dog in a microwave, because the adverts said it would do whatever her old oven did - who the hell dries a dog in an oven! She won her case when she sued the microwave company  :shakehead

 
I don't believe I suggested the garage was BD4 I just gave a generic example apologies if this confused. Considering fire rated clips are generally tested at 930°C for two hours although this may vary between manufacturers so the use of over the counter clips is likely to give a two hour duration.


So why even mention it???

There is little point answering any questions posted with irrelevant regulations that have minimal importance, relevance, or safety implications to the question in hand..

Recap#1   the whole thread is about some 6.0mm T&E in a garage......

Hi, I am shifting our electric oven to the other side of the kitchen which will require a new run of 6mm twin and earth back to the consumer unit in the integral garage, the run is aprrox 11m with 9.5 m in the garage, the last bit through stud and plasterboard walling. Which is the best method to run it in the garage, cable clips butting up to the ceiling, 25mm plastic conduit, or plastic trunking 25mm x 16mm, there will be five 90 degree bends.

Thanks

Pete




Recap#2  your first response was about premature collapse....

Fixings will need to be as such that the cable will not prematurely collapse in the event of a fire.




Recap#3(a)  When I asked how soon you consider is too soon for premature collapse of 6.0mm in a domestic garage..

you started waffling on about escape routes... 

I was referring to what can be considered an escape route. In terms of fire safety you have defined escape routes and routes of passage leading to the defined routes this is likely to encompass most of the floor space. The space of time a person occupies this space is not a concern as it does not change the fact of whether it is or is not a route of escape. My comment was not referring to the length of time that cable support will collapse.




Recap 3(b)   and then BD4 routes...?

Yes I remember what I posted I was later considering an escape route being more complicated that just the defined escape routes which may or may not have bought about the Regulation change. The duration for premature collapse will be variable whereby a BD4 route may require 2 hours before premature collapse takes place.




I will try asking again...

(Note:  I am not asking for any specifications or interpretations of what you consider various manufactures specific fixings can or cannot withstand in the event of a fire..

I am more than capable of reading manufactures specifications data.)

What I want to know is..

How long would you be expecting a single piece of 6.0mm, approx 9.5m long, to  to stay fixed to a single entry garage wall,

before you considered it had failed prematurely?  

Especially as your first response to the initial question was

"Fixings will need to be as such that the cable will not prematurely collapse in the event of a fire."

I would hazard a guess that 99.999999999% of standard domestic single entry garages;

Could be evacuated within less than 5minutes....

and are not normally occupied...

and are not escape routes...

So premature collapse, and mentioning 2hrs and/or BD4.. etc..

is possible as relevant as referring to 740.55.9,  just in case Mr homeowner is repairing Dodgem cars in there as well!!

Please can you tell me how many minutes you consider is premature for this 9.5m or 6.0mm T&E..

A nice simple short answer will do...

I'll give you some suggestions that may help...

5min / 10min / 15min / 20min / greater..

:coffee

 
Or cheaper option...

Bog standard 6.0mm clips...

https://www.screwfix.com/p/lap-cable-clips-grey-for-twin-earth-cable-6mm-pack-of-100/9411f

And a few strategic loops cut off a bit of galv band..

https://www.screwfix.com/p/ced-galvanised-all-round-band-12mm-x-10m/18298?_requestid=658207

9.5m of cable isn't going to fall very far in the event of a few clips melting...

we are not talking of long cable runs through large commercial/retail/industrial complex!  

Little point keeping your cables on a unoccupied garage wall looking nice for hours during a fire...

When the garage ceiling will have probably collapsed well before then! 

https://www.gov.uk/government/publications/fire-safety-approved-document-b

Guinness

 
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