Cable clips as per 18th edition.

[ZippyMo]

Friends,

I'm rewiring my brothers house tomorrow. Can someone tell me if the new 18th edition allows me to use the plastic cable clips to secure the cables to joists etc?
Or do I have to replace them with metal ones?

Thanks

ZippyMo
Trainee Sparks

 

[Nigel]

No tin hat, plasterboard is rated at 30 minutes. After 30 minutes of fire would collapse be classed as premature?

Do you think 30 mins is a realistic time frame for the alarm to be raised. The Fire Brigade get to the property, set up, enter the building and put the fire out?

 

[freddo]

I didn't think they would enter once the ceiling had collapsed? By that stage of the fire I can't imagine there would be anyone left alive to rescue?

 

[Midwest]

Do you think 30 mins is a realistic time frame for the alarm to be raised. The Fire Brigade get to the property, set up, enter the building and put the fire out?

Dunno what the typical/required response times are; but I guess if someone is in said building fire for longer than 30mins, in a standard domestic premises, they'd be a goner, so unlikely the fireman would required enter to save lives. Other buildings would have different fire building standards.

Edit too slow.

 

[Nigel]

No tin hat, plasterboard is rated at 30 minutes. After 30 minutes of fire would collapse be classed as premature?

Do you think 30 mins is a realistic time frame for the alarm to be raised. The Fire Brigade get to the property, set up, enter the building and put the fire out?

Just done a surface fire alarm install, 90% normal clips but fire rated ones to ensure the cable cannot fall or create a hazard in such a situation..
The misconception is that all the fixings have to comply yet the install has to satisfy the point the run will not collapse and get tangled in the gear of the fire brigade so a fire rated clip in suitable positions will be adequate.

That is dog poo in my opinion. BS5839 covers two points when talking about securing cables.

The first is to prevent premature collapse to protect escapees or rescuers. This is actually Bs7671 not 5839.

The second is to maintain the critical signal path of the circuit to ensure the system continues to operate for the rated duration.

Installing 90% non- fire-proof clips is a complete bodge I am afraid is now there is a risk that the integrity of the circuit will be compromised during a fire and that is not ok.

BS 5839 gives maximum distances for cable supports and states that all cable supports must be non-combustable. To have cable possibly rated at 120 minutes and plastic clips is a nonsense.

 

[Nigel]

I didn't think they would enter once the ceiling had collapsed? By that stage of the fire I can't imagine there would be anyone left alive to rescue?

The regulation was brought in to protect fire fighters. In a large building they certainly would clear out room by room.

 

[Midwest]

The regulation was brought in to protect fire fighters. In a large building they certainly would clear out room by room.

But in a 'large' building, it would have additional fire preventative measures and fire fighting equipment. Not what the OP has asked.

 

[Nigel]

But in a 'large' building, it would have additional fire preventative measures and fire fighting equipment. Not what the OP has asked.

That would be covered under different Standards. BS7671 does not state the size or type of building. It just simply states that all cables must be secured against premature collapse.

 

[Midwest]

The regulation was brought in to protect fire fighters. In a large building they certainly would clear out room by room.

That would be covered under different Standards. BS7671 does not state the size or type of building. It just simply states that all cables must be secured against premature collapse.

You like an argument. Is not 30mins the minimum standard?

 

[Darkwood]

@essex

The installation of the cabling and/or its containment in which it would be subject to fire rated fastenings is down to installers judgement and that is still complies to relevant sections of the BS5839 and BS7671.

The 90% none fire rated fixings and 10% fire rated was an example of an install I am on at present and was not a number that would reflect all installs, so to make a statement the it is 'dog poo' is only an opinion based on the very limited info' presented and the lack of knowledge you have about my install.

Having said that, if you were fixing a FP200 along an exposed wooden support beam that would require you to use fire rated fixings then given the standard spacing you clip (say 3 per-meter) then you get a P-Clip every 3m, it only has to support the cable between that clip fire rated clip and the next, the only other step I would take would be to use long screws due to the beam been made of wood, as mentioned by others, it only has to survive a set period that allows the fire services to evacuate and/or check the premises, these fixings would last as long as the structural integrity of the wooden beam they are fastened to at which point the fire service would judge the building section too unsafe to enter anyway.

I have had my work checked and passed by BC and the Fire Services before it was commissioned, I would be happy to stand corrected on the matter if you can provide the relevant regulations to say I have done it wrong but as I read it, it is subject to my assessment and judgement which is reflective of the nature of the building and the runs I am doing, so I find it a strong response to call out my work and make a judgement like that when you have never even stepped foot in the building nor do you know anything about the install.

 

[Darkwood]

BS5839 -1
26.2 (f)
States methods of support should be non-combustible then goes to note 10 which makes the case that this recommendation precludes the use of plastic clips, ties and trunking..
(I can somewhat see why this regulation is misleading)

Now the interpretation of this regulation is somewhat ambiguous IMHO as all clips/ties or trunking in effect are supporting the cable in some fashion it could be argued so doubling the clips used even if not required could be taken they too are supporting the cable too, but I take from this is a cable needs to be suitably mechanically supported with fire rated solutions, if you can show this then there is no reason a number of the fixing cannot be just standard plastic fixings, BS7671 expand on this regulation.

Note here that BS7671 521.10.202
Note3 This regulation precludes, for example , the use of non metallic cable clips or cable ties as a sole means of support.

Note4 Suitably spaced steel or copper clips, saddles or ties are examples that will meet the requirement of this regulation.

This is as I have installed my system and meets the requirements set out in the BS7671 and that of the BS5839 in which the BS7671 expands on.

 

[Nigel]

BS5839 -1
26.2 (f)
States methods of support should be non-combustible then goes to note 10 which makes the case that this recommendation precludes the use of plastic clips, ties and trunking..
(I can somewhat see why this regulation is misleading)

Now the interpretation of this regulation is somewhat ambiguous IMHO as all clips/ties or trunking in effect are supporting the cable in some fashion it could be argued so doubling the clips used even if not required could be taken they too are supporting the cable too, but I take from this is a cable needs to be suitably mechanically supported with fire rated solutions, if you can show this then there is no reason a number of the fixing cannot be just standard plastic fixings, BS7671 expand on this regulation.

Note here that BS7671 521.10.202
Note3 This regulation precludes, for example , the use of non metallic cable clips or cable ties as a sole means of support.

Note4 Suitably spaced steel or copper clips, saddles or ties are examples that will meet the requirement of this regulation.

This is as I have installed my system and meets the requirements set out in the BS7671 and that of the BS5839 in which the BS7671 expands on.

I am not sure what edition of BS5839-1 you are working to but here is the extract from the current edition:

My notes in RED

26.2
f) Methods of cable support should be non-combustible and such that circuit integrity is not reduced below that afforded by the cable used, and should withstand a similar temperature and duration to that of the cable, while maintaining adequate support.

This is very clear. It does not say 'some cable supports' It does not say 'many' or 'most', it simply says 'cable supports'. This means that ALL CABLE SUPPORTS should be non-combustible and afford the same level of integrity to that of the cable installed.

NOTE 10:
In effect, this recommendation precludes the use of plastic cable clips, cable ties or trunking, where these products are the means of cable support.

Again very clear -
preclude
/prɪˈkluːd/
verb
3rd person present: precludes

1. prevent from happening; make impossible.

You are not permitted to use plastic cable clips, cable ties or trunking as a cable support. It does not use the word 'sole' that you have put in your reply to me before the words cable support.

NOTE 11:
Experience has shown that collapse of cables, supported only by plastic cable trunking, can create a serious hazard for firefighters, who could become entangled in the cables.

I really do not know how better written a regulation can be. It is crystal clear. Any plastic clips, ties or trunking as a cable support is not acceptable.

 

[Nigel]

It is also worth mentioning that when there is a clash between BS7671 and BS5839 then 5839 ALWAYS overrules.

 

[Strima]

What does part 6 say about cable supports?

 

[Darkwood]

@essex

I have the BS5839-1 2017 and the BS5839-6 2013 which to my knowledge are still the latest versions.
Given that the regulation concerning fire rated supports in both the BS5839-1 and the BS7671 18th edition are there for the exact same reason and the body which designed and constructed these particular regulations are the one and the same then I would conclude that the BS7671 18th edition been the most up to date is the one that is accurate and thus in this case would mean it expands on the older version of the regulation in the BS5839-1.

I do not get why you think the BS5839 trumps the BS7671 as it is subjective to regulation, dates of release, amendment etc, I agree there will be extra regulation applicable under BS5839 but disagree with a sweeping claim that BS5839 always overrules, up until the recent release of the BS5839-1 (2017)there were forthcoming amendments found in the more recent versions of BS7671 in areas that crossed over that eventually were implicated in the 2017 edition ...

 

[Nigel]

@essex

I have the BS5839-1 2017 and the BS5839-6 2013 which to my knowledge are still the latest versions.
Given that the regulation concerning fire rated supports in both the BS5839-1 and the BS7671 18th edition are there for the exact same reason and the body which designed and constructed these particular regulations are the one and the same then I would conclude that the BS7671 18th edition been the most up to date is the one that is accurate and thus in this case would mean it expands on the older version of the regulation in the BS5839-1.

I do not get why you think the BS5839 trumps the BS7671 as it is subjective to regulation, dates of release, amendment etc, I agree there will be extra regulation applicable under BS5839 but disagree with a sweeping claim that BS5839 always overrules, up until the recent release of the BS5839-1 (2017)there were forthcoming amendments found in the more recent versions of BS7671 in areas that crossed over that eventually were implicated in the 2017 edition ...

This is a fundamental teaching in fire alarm courses. When there is a clash then BS 5839 overrules. Furthermore BS 7671 does not cover fire alarms and directs us to BS 5839.

As I have stated. Cable integrity of fire alarms is not just about protecting fire fighters. You seem to have brushed over all my other points???