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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Fire Safety => Topic started by: jokar on August 19, 2008, 07:10:06 PM

Title: Bs 5839
Post by: jokar on August 19, 2008, 07:10:06 PM
I am aware that a new or revised standard is due our this year.  I was told originally that it would be October 2008, has anyone any news on this.
Title: Bs 5839
Post by: Ricardo on August 19, 2008, 08:39:08 PM
Jokar
There is an updated version of the 2002 standard already out,(31st March 2008) entitled BS 5839-2:2002+A2:2008.
Which supersedes BS 5839-1:2002+A1:2004.
Title: Bs 5839
Post by: Graeme on August 19, 2008, 08:43:55 PM
more cash to splash out..

why can't they just sell the ammended parts?
Title: Bs 5839
Post by: jokar on August 19, 2008, 09:31:40 PM
Is it wqorth getting for the amendments or are they just minimal?
Title: Bs 5839
Post by: CivvyFSO on August 20, 2008, 09:55:24 AM
Fairly minimal. Most of it seems to be updated to take into account other new standards, i.e. reference to any HTM will be the most recent HTM.

Acknowledgement of L5 systems possibly being localized detection to compensate for departure from guidance.

A half page modification in chapter 11, system components. Mainly what different detectors and cables etc should conform to.

A bit on detection zones and MCPs in stairwells.

A bit extra on visual alarms.

Reference to accessibility requirements under building regs re: impaired hearing.

Reference to mounting switches no higher than 1.2m due to guidance in Bregs ADM. It still suggests 1.4m as standard though.

An interesting one, possibly important to know if you are a designer/installer: NOTE 4 In a Category L2 or L3 system, detectors in rooms opening onto escape routes are provided only to give a warning of fire before it affects the escape routes. Detection in voids above or below the rooms might not be necessary for this purpose (e.g. if fire resisting construction separates a void from the adjacent escape route).

Various other stuff on voids.

Acknowledgement that cables should be secured in such a way that they remain secured for the same duration they are intended to survive in a fire. (And also of the risk to firefighters of collapsing cables)

A bit on rcd's.

Modification to 12 month test.

That is about it.
Title: Bs 5839
Post by: Ricardo on August 20, 2008, 11:31:33 AM
A bit more in Sec 2 Ch 12 re System Integrity,where standby batts/PSU are housed in seperate enclosures & in Ch27 a bit on Radio linked system components, also a bit more in Sec 6 re non-routine attention, on appointment of new service organisation.
Title: Bs 5839
Post by: Allen Higginson on August 20, 2008, 12:14:49 PM
Quote from: CivvyFSO
Fairly minimal. Most of it seems to be updated to take into account other new standards, i.e. reference to any HTM will be the most recent HTM.

Acknowledgement of L5 systems possibly being localized detection to compensate for departure from guidance.

A half page modification in chapter 11, system components. Mainly what different detectors and cables etc should conform to.

A bit on detection zones and MCPs in stairwells.

A bit extra on visual alarms.

Reference to accessibility requirements under building regs re: impaired hearing.

Reference to mounting switches no higher than 1.2m due to guidance in Bregs ADM. It still suggests 1.4m as standard though.

An interesting one, possibly important to know if you are a designer/installer: NOTE 4 In a Category L2 or L3 system, detectors in rooms opening onto escape routes are provided only to give a warning of fire before it affects the escape routes. Detection in voids above or below the rooms might not be necessary for this purpose (e.g. if fire resisting construction separates a void from the adjacent escape route).

Various other stuff on voids.

Acknowledgement that cables should be secured in such a way that they remain secured for the same duration they are intended to survive in a fire. (And also of the risk to firefighters of collapsing cables)

A bit on rcd's.

Modification to 12 month test.

That is about it.
Where does it mention risk to firefighters??
Title: Bs 5839
Post by: CivvyFSO on August 20, 2008, 12:19:04 PM
26.2 Note 9

NOTE 9 Experience has shown that collapse of cables, supported only by plastic cable trunking, can create a serious hazard
for fire-fighters, who could become entangled in the cables.
Title: Bs 5839
Post by: Allen Higginson on August 20, 2008, 12:44:55 PM
Quote from: CivvyFSO
26.2 Note 9

NOTE 9 Experience has shown that collapse of cables, supported only by plastic cable trunking, can create a serious hazard
for fire-fighters, who could become entangled in the cables.
Apologies - I hadn't read down that far,although I haven't used plastic as sole support for quite a while now.
The only thing is does this indicate the end of plastic support systems for cables in general because it's not only fire cables that go above ceilings?
Title: Bs 5839
Post by: jokar on August 20, 2008, 01:06:51 PM
Best I get a copy methinks.
Title: Bs 5839
Post by: Allen Higginson on August 20, 2008, 01:09:40 PM
Quote from: jokar
Best I get a copy methinks.
I'd reckon so as there are a lot of these wee notal additions here and there.
Title: Bs 5839
Post by: CivvyFSO on August 20, 2008, 01:53:14 PM
Quote from: Buzzard905
The only thing is does this indicate the end of plastic support systems for cables in general because it's not only fire cables that go above ceilings?
It would clearly be prudent to take that into account, but the standard can only recommend this for cables relative to the fire alarm. Other standards may have been updated, maybe there is a sparky/IT bod out there who can answer that.
Title: Bs 5839
Post by: Allen Higginson on August 20, 2008, 03:01:41 PM
Quote from: CivvyFSO
Quote from: Buzzard905
The only thing is does this indicate the end of plastic support systems for cables in general because it's not only fire cables that go above ceilings?
It would clearly be prudent to take that into account, but the standard can only recommend this for cables relative to the fire alarm. Other standards may have been updated, maybe there is a sparky/IT bod out there who can answer that.
Judging by what I've seen in any install recently (non-fire) the plastic tie (if they have used one!) is alive and well!
Title: Bs 5839
Post by: Graeme on August 20, 2008, 04:56:35 PM
Quote from: CivvyFSO
26.2 Note 9

NOTE 9 Experience has shown that collapse of cables, supported only by plastic cable trunking, can create a serious hazard
for fire-fighters, who could become entangled in the cables.
and i used to always tell installers it was to keep the integrity of the cable during a fire.

like you say-what about the ton weight of data cables etc that are in big plastic trunkings? If there was a fire would the fire cable be the only one to drop?

it should be the same for everyone installing any type of cable.
Title: Bs 5839
Post by: Graeme on August 20, 2008, 04:57:59 PM
Quote from: jokar
Is it wqorth getting for the amendments or are they just minimal?
ammendments 1 wasn't.
Title: Bs 5839
Post by: kurnal on August 20, 2008, 06:07:55 PM
Ref plastic cable ties and the BS5839 reference to firefighters- I agree and is a valid point- but of course from another viewpoint- the RRO is clear that firefighters are not relevant persons.
So in a fire risk assessment under the RRO are plastic ties supporting fire alarm cables a significant finding?
Title: Bs 5839
Post by: Allen Higginson on August 20, 2008, 06:21:57 PM
Quote from: kurnal
Ref plastic cable ties and the BS5839 reference to firefighters- I agree and is a valid point- but of course from another viewpoint- the RRO is clear that firefighters are not relevant persons.
So in a fire risk assessment under the RRO are plastic ties supporting fire alarm cables a significant finding?
Im not conversant with the RRO but they are not permitted as sole means of support for fire cables.Similarly,I will allow our installers to use plastic trunking provided they have metal P clips at regular intervals.
Title: Bs 5839
Post by: jokar on August 20, 2008, 06:26:21 PM
If it is stated that the FA is to the BS and the cables are not installed correctly then yes that could be a significant finding.  However, what can be done after install may be limited by the cable runs of all the cables together.  After all, as has been noted above it does not apply to other cables.

Anyway what happened to professional firefighting?
Title: Bs 5839
Post by: CivvyFSO on August 21, 2008, 10:17:39 AM
Quote from: kurnal
Ref plastic cable ties and the BS5839 reference to firefighters- I agree and is a valid point- but of course from another viewpoint- the RRO is clear that firefighters are not relevant persons.
So in a fire risk assessment under the RRO are plastic ties supporting fire alarm cables a significant finding?
Quite right, no they would not be a significant finding. But think about a recently installed alarm, if it was not to this standard and someone got hurt because of it, I could imagine that the installer could be for the high jump if someone was aware that this requirement had been ignored. It wouldn't be a failing under the RRO, and BS5839 is not retrospective so old systems cannot be required to be updated as BS5839 changes.
Title: Bs 5839
Post by: Galeon on August 21, 2008, 10:39:19 AM
No excuse for all plastic ties , use a metal tie every third fixing on the tray (if its there) or p clipped to slab .
Title: Bs 5839
Post by: Thomas Brookes on August 21, 2008, 11:33:20 AM
This is were I think the BS fail us all, they should get off the fence and clearly state that they want metal fixings everywhere or not, I think they should also look into the practicalities of fitting p clips etc insde trunking.
Technically just having your cable on a metal tray is possibly ok as it is being supported by the tray and the tray is giving the cable more support than the time the cable will last in a fire suituation.
The big problem with metal ties is that they dont grip the cable so unless you put a plastic tie on it you end  up with slack cables.
Title: Bs 5839
Post by: Galeon on August 21, 2008, 11:43:37 AM
Still more choice to be had , use the copper banding we use to use on the mineral
Title: Bs 5839
Post by: wee brian on August 21, 2008, 01:50:00 PM
Quote from: CivvyFSO
Quote from: kurnal
Ref plastic cable ties and the BS5839 reference to firefighters- I agree and is a valid point- but of course from another viewpoint- the RRO is clear that firefighters are not relevant persons.
So in a fire risk assessment under the RRO are plastic ties supporting fire alarm cables a significant finding?
Quite right, no they would not be a significant finding. But think about a recently installed alarm, if it was not to this standard and someone got hurt because of it, I could imagine that the installer could be for the high jump if someone was aware that this requirement had been ignored. It wouldn't be a failing under the RRO, and BS5839 is not retrospective so old systems cannot be required to be updated as BS5839 changes.
Metal clips are as much about circuit integrity as they are about fire fighter safety. So it could be a significant finding.
Title: Bs 5839
Post by: Graeme on August 21, 2008, 04:57:41 PM
Quote from: Thomas Brookes
This is were I think the BS fail us all, they should get off the fence and clearly state that they want metal fixings everywhere or not, I think they should also look into the practicalities of fitting p clips etc insde trunking.
Technically just having your cable on a metal tray is possibly ok as it is being supported by the tray and the tray is giving the cable more support than the time the cable will last in a fire suituation.
The big problem with metal ties is that they dont grip the cable so unless you put a plastic tie on it you end  up with slack cables.
Thomas

get yourself one of those magic guns for metal ties. I have one and you can get the tie as tight as required.
Title: Bs 5839
Post by: Allen Higginson on August 21, 2008, 05:28:18 PM
Quote from: Thomas Brookes
This is were I think the BS fail us all, they should get off the fence and clearly state that they want metal fixings everywhere or not, I think they should also look into the practicalities of fitting p clips etc insde trunking.
Technically just having your cable on a metal tray is possibly ok as it is being supported by the tray and the tray is giving the cable more support than the time the cable will last in a fire suituation.
The big problem with metal ties is that they dont grip the cable so unless you put a plastic tie on it you end  up with slack cables.
To be fair I would have metal ties as intermediate support with metal as the main.Even if the plastic give and there is slack it wouldn't be significant to warrant total metal support.
Our guys run cables in 20mm conduit and saddles above ceilings so no risk of cables dropping unless the ceiling goes!