Cable collapse with false ceilings

[pc1966]

Related to another post, I am looking at running some network cable across a corridor above a false ceiling system. Is the ceiling support system considered adequate to prevent premature cable collapse in the event of a fire?

My immediate though is it has to be, otherwise the support system itself is as much of a hazard to fireman, etc, but that got me wondering what really the situation really is in respect to the regs.

 

[westward10]

No a ceiling grid system is not a means of cable support although I stand corrected if you find this a suitable installation method in BS7671.

 

[Dartlec]

I think this is one of those cases like so many where they haven't specified what is 'suitable'. It may depend on whether the existing ceiling support system is considered a fire-resistant structure or not...

Amusingly, this post is now top of the google searches for it though (but that may be just for me...)

BEAMA have a document from May this year that might shed some light

From the introduction:

Unfortunately, the term premature collapse was not defined and rather than offer clarity to installers this may have added confusion. Furthermore, the fact that there are currently no fire rating tests for the performance of cable management systems within the harmonised product standards, installers have a problem when their clients specify fire safety performance levels for installations.​

 

[westward10]

I think this is one of those cases like so many where they haven't specified what is 'suitable'. It may depend on whether the existing ceiling support system is considered a fire-resistant structure or not...

Amusingly, this post is now top of the google searches for it though (but that may be just for me...)

BEAMA have a document from May this year that might shed some light

From the introduction:

Unfortunately, the term premature collapse was not defined and rather than offer clarity to installers this may have added confusion. Furthermore, the fact that there are currently no fire rating tests for the performance of cable management systems within the harmonised product standards, installers have a problem when their clients specify fire safety performance levels for installations.​

Whether the ceiling is fire resistant or not and it is generally rare for a ceiling grid to be so it is not a cable support system. If a ceiling grid is constructed to be a fire barrier then this is its purpose and any cable system dropping onto it may well compromise its effectiveness.

 

[Dartlec]

It's true that there might be bigger issues than your cable if the ceiling came down on fire fighters - but you aren't responsible for installing that, so I'd be tempted to fix the network cable to the ceiling with P clips or something suitable...

It may reduce the chances of the cable being damaged in future too by other trades...

 

[Dustydazzler]

Can’t you drop say every third tile and pop a bit of all round band screwed to the wall or structure

 

[pc1966]

Thanks for all the feedback. I still have to check the area in detail, originally it was not supposed to be my job to put the cables in

The corridors might be no wider than 3m from memory, so I may be able to span it in one go with some cable tray and use stainless ties on that, or even some spare 100x50 steel trunking that is kicking around somewhere.

Fixing stuff to the underside of the concrete ceiling is a possibility, but it might be a bit high for safe reach from any of the available ladders so I had hoped to fix things to the walls not far above the false ceiling height if possible.

 

[e-spark]

Related to another post, I am looking at running some network cable across a corridor above a false ceiling system. Is the ceiling support system considered adequate to prevent premature cable collapse in the event of a fire?
My immediate though is it has to be, otherwise the support system itself is as much of a hazard to fireman, etc, but that got me wondering what really the situation really is in respect to the regs.

I use P clips t the underside of the ceiling, stainless cable ties or round band if there are a few cables to run, fairly quick and easy.

 

[pc1966]

I use P clips t the underside of the ceiling, stainless cable ties or round band if there are a few cables to run, fairly quick and easy.

My initial though for a single CAT-6 sort of cable was stainless ties to the steel ceiling support wires, as the weight of the cable is negligible compared to the tiles, etc. But then I wondered if those might be considered acceptable or not, hence this thread.

The false ceiling is quite high, probably 2.5-3.0m up, and the actual ceiling could be about 1m above that, but as I was not originally doing this job I did not measure it up...

I don't have ladder that can safely reach that far which is why I was looking for options that could be done fairly easily at lower height such as cable tray or even steel conduit if the span is not too far for unsupported tube (it would be through both walls, so very well supported at the ends).

A catenary wire might be a simpler solution here for 1 or 2 CAT-6 cables.