Fire Alarm Trunking

Discuss all things fire related.

Moderator: Moderators

Post Reply
User avatar
Blackstone
Grand Shidoshi
Grand Shidoshi
Posts: 1005
Joined: Mon Mar 07, 2011 11:17 am
Twitter: https://twitter.com/#!/GlenDoc
Industry Sector: Manufacturing / Marine / Oil & Gas
Location: Kent

Fire Alarm Trunking

Post by Blackstone » Wed Jun 06, 2018 3:47 pm

Hi all,

Fire regulations are really not my strong point so hopefully one of the fire experts can help...

We recently had a new fire alarm systems installed across our site including new sounders, flashers, control panels and wiring.
I came into my office on Monday morning to find that a run of trunking had come detatched from the ceiling and was only being held up by the sounder in the center of the ceiling and where the cables go through walls into other rooms.

We had someone come in today to rectify (not the same person that installed it) and he stated that he thought the trunking should be metal and not plastic.
We got in contact with our main expert (at the well know company, who commisioned the system) and he said the guy is part right. He said it can be plastic but should have metal clips at given intervals along the trunking.

Could someone please shed some light on who might be correct and maybe where i could find the information.

Many thanks, as i really wouldn't know where to start looking .scratch

./thumbsup.. Glen
'Train people well enough so they can leave, treat them well enough that they don't want to!' - Richard Branson

hardhat
Newbie
Newbie
Posts: 12
Joined: Wed Oct 12, 2016 4:05 pm

Re: Fire Alarm Trunking

Post by hardhat » Wed Jun 06, 2018 3:53 pm

Hi,

Yes, basically the BS requires the cables to be secured in such a way so that they will not fall during a fire. The reason for this is that in a fire, if the plastic melts and the cables fall/sag, it is a real hazard for the fire service entering the building (as well as people trying to escape, although it would be pretty darn hot at that point!).

So yes, metal conduit is one option, or it is usual for metal clip things to be screwed inside the trunking holding the cables secure, so if the trunking starts to melt the cables won't sag.

If they are a BS-accredited fire installation company, or they have agreed to install to BS 5839, then complain and get them back in as it isn't to standard.

Hope this helps!

hardhat
Newbie
Newbie
Posts: 12
Joined: Wed Oct 12, 2016 4:05 pm

Re: Fire Alarm Trunking

Post by hardhat » Wed Jun 06, 2018 4:00 pm

Further to my previous response:
BS-5839-1:2002 Para 26.2(g):
"f) Methods of cable support should be such that circuit integrity will not be 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.
NOTE 7 In effect, this recommendation precludes the use of plastic cable clips, cable ties or trunking, where these products are
the sole means of cable support."

User avatar
Blackstone
Grand Shidoshi
Grand Shidoshi
Posts: 1005
Joined: Mon Mar 07, 2011 11:17 am
Twitter: https://twitter.com/#!/GlenDoc
Industry Sector: Manufacturing / Marine / Oil & Gas
Location: Kent

Re: Fire Alarm Trunking

Post by Blackstone » Thu Jun 07, 2018 8:30 am

Hi Hardhat,

Thanks for that. It's helped no end ./thumbsup..

Just checking if they stated in the contract it shall be installed in accordance with BS5839, then will get them back to resolve.

Best regards

Glen .salut
'Train people well enough so they can leave, treat them well enough that they don't want to!' - Richard Branson

Post Reply

 

Follow us on Twitter Find us on Facebook Find us on on LinkedIn

Terms of Use Privacy Policy