N
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
- prevent from happening; make impossible.
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.