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Topic Title: Should existing fire alarm cables wired in normal T&e be upgraded to
Topic Summary: Fire proof cables?
Created On: 12 January 2018 07:41 PM
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 12 January 2018 07:41 PM
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Weirdbeard2

Posts: 132
Joined: 29 November 2017

I am asking out of interest on behalf of a local charitable installation who's latest quarterly inspection by their ongoing fire alarm inspection company has suddenly recommended that all the detectors and call points should be rewired in fire proof cables.....has there been a recent change in regs? It is a twenty + year old install and has been inspected tested quarterly checked by the same firm ever since.

Any info greatly appreciated
 12 January 2018 07:44 PM
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daveparry1

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I say no?
 12 January 2018 07:46 PM
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Weirdbeard2

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Thanks for the prompt reply Dave
 12 January 2018 08:24 PM
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NE1

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If it was ok by the regs at the time of installation then it's ok now. Unless any changes are made, then it has to be brought up to current standards.
The only other thing is if the insurance company insists on it being to current standards.
 12 January 2018 09:30 PM
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leckie

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OK, I am no expert on this but......

Surely we know that this old chestnut about regulations not being retrospective is hogwash? It does not say that in BS7671, not in BS5839 or BS5266.

The other thing to consider is that a safety system cannot be judged on the same basis as the wiring regulation ( IMO).

So I think that the overriding thing is the fire risk assessment, (Dave69 can let us know if he reads this post).

So BS5839 pt 1 used to allow the detection circuit/s to be in cables that were not fire rated, but I cannot remember what version of the standard this was - over twenty years ago I think though. Well as I recall it didn't state you could wire the detection circuit in whatever you wanted to, it was that there was a cable specification for the alarm (sounder) circuit. Howev this was changed. So I suppose you have to ask yourself why. And then base any recommendation on what additional risk the detection circuit wired in twin and earth actually represents.

How would you assess emergency escape lighting that was not to the latest standard? Would you be happy to say that a lux level down the escape route was not to the current standard is safe on a risk assessment? I don't think I would be, but we don't have to make his statement on a periodic inspection, we just have to report departures from the current standard.

So I would think that the fire risk assessment should make the necessary recommendations and may use the findings in a periodic inspection to help assess the risk. No clear answer then, but an expert might give a much better answer of course.
 12 January 2018 10:14 PM
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alancapon

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I don't recall which version of BS5839 first required fire proof cables, but it was many years ago. I would expect t&e cables to have been recommended for replacement a long time ago. Under the 2013 and 2017 versions even white FP200 is a non-compliance, although doesn't necessarily need replacing. Fire systems should be inspected to the latest standard, not something from a past era. Same goes for emergency lights and fixed wiring too!

Regards,

Alan.
 13 January 2018 06:31 AM
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leckie

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Yes I agree Alan, any PIR is based on the current standard. My point is that the PIR is not itself the document that declares what action is required, I think that is based on a FRA which would take into account any findings within a PIR.

BS 5839 pt1 required the sounder circuit wiring to be specifically fire rated up until the 20002 update. The 1988 version allowed detection circuits to be wired in non fire rated cable.

However, if the departure was now included on a PIR, I think it would be a unlikely that anyone seeing the report would then indicate on an updated FRA that the wiring system was deemed suitable.

This whole thing about regulations not being retrospective in regards to BS7671 drives me mad. Sometimes regulations are retrospective and sometimes they are not. If you did an EICR and found an old Lewden external 13A socket with no RCD protection would you say this was acceptable because it wax installed in 1972? Or would you code it C2? I know what I would say. So regulations can of course be retrospective.

But regarding safety system installations such as BS5839 and BS5266, I would imagine that installations would normally be required to be upgraded to the latest standards in most cases for safety and the management of the systems in terms of false alarms, etc. For example if you were the responsible person for overseeing the fire alarm for a block of student flats and a PIR noted that there was no protective covers over the break glass call points, how would you respond? Would you say that you did not consider this a risk to the management of the system? How about if every time there was a glass pressed by a merry occupant on the way back from an evening of shenanigans and this resulted in the evacuation of the entire building in the early hours of the morning? And the attendance of the fire services? This was exactly the case for the student accommodation that one of my sons lived in at university. They had the building covered with CCTV and used to fine the occupants if they were caught setting off the alarms. I reckon the responsible person would be fitting the covers pretty quick now on the basis that the installed system did not comply with BS5839.

Edited: 13 January 2018 at 06:54 AM by leckie
 13 January 2018 08:17 AM
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lyledunn

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Leckie is right to point out that this is a matter of risk assessment. No information has been given by WB in relation to the nature of the building, how it is being used, what purpose the FA system is required to perform, the other, perhaps compensatory, fire safety control measures that are in place etc.


-------------------------
Regards,

Lyle Dunn
 13 January 2018 08:41 AM
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leckie

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Well I am no expert on the FRA side of things, but from my reading it seems that the FRA is the thing that has to bring together all the various reports and statutory requirements and implement the overall fire strategy and protective measures required.

I am always amazed when I have had a walk around a building with a fire officer or fire risk assessor. They are often not overly concerned about exact compliance with BS5839 or Bs5266. They take an overall view of the risks, and a Lyle says, they often suggest additional protection in other areas, say fire doors or compartments, as art of an verbal strategy to reduce the risk to what they assess as a satisfactory level. You need real expertise across the entire fire risk prevention methods to be able to make those sort of judgements.
 13 January 2018 08:46 AM
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Fm

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I would have thought that a system designed to safe lives and property should be up to date.
Detectors have a 10 year life span I think so they would need replacing
What's the sounder circuit wired in, will this keep going in the event of a fire?
Fire risk assessment and a competent contractor are all that are needed
Maybe a consultant too
 13 January 2018 11:32 AM
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Weirdbeard2

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Thanks for the replies, it is a fair sized detached former house now used by an amateur theatre group for rehearsals, prop storage costume making, admin etc. As far as I know they do have regular fire risk assessments, and the same fire alarm contracting company (large nationwide) has always done the 4 times a year inspection and test since about 94/95 when it was installed I am pretty sure all detectors have been changed as and when necessary and the main panel was upgraded a couple of years ago.

The Sounders are in white FP.
 13 January 2018 04:34 PM
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Dave69

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As you say the sounders are wired in white FP were these installed when the panel was changed a couple of years ago? It would be interesting to see the certification issued when the new panel was installed. I guess it is a bog standard conventional system rather than an addressable one and not a two wire system

Has any mention been made about rewiring the mains supply to panel?

The FRA is an important document, but the person writing it doesn't have to really confirm the fire alarm conforms to BS standards but if they recommend additions they will probably say something along the lines of "fixed heat detection linked to exisiting fire alarm system in accordance with BS5839-1............to be installed in kitchen area,,,,,"

You say this is a large detached house, so wiring would be required to be standard fire resisting cable, but I would not say the entire building is not of high risk, certain areas may be, I.e. prop making and costume making and storage so why is the system being inspected every 3 months when really every 6 months would be ok. Do people live in the premises as this would make a difference
 14 January 2018 10:51 AM
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Weirdbeard2

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Thanks for the reply Dave, I am pretty sure it is the standard conventional type, there was no certificate issued for the panel change, just a brief note in the maintenance log and an invoice and no mention of the mains supply. The sounder FPs are original cables.

I believe it is inspected quarterly as it is on redcare although the fire brigade dont get called automatically.

I must admit I am not sure how having fire proof cables are a great deal safer than the existing arrangement, I would have thought if a twin and earth detector/call point cable is subject to prolonged fire the insulation would fail and the cable fault cause the alarm to operate, fire proof cable would only serve to delay the alarm from sounding.
 14 January 2018 11:12 AM
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alancapon

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A conventional fire panel will have an "end of line" resistor at the last detector to monitor against cable breaks. If this resistor is no longer present, or the cable cores are shorted, this should raise a "fault" on the panel. A detector sensing fire will place a low value resistor across the cable cores, and this is the only condition that should indicate "fire" on the panel. Fire damage to the detector cabling is likely to give a "fault" indication at the panel.

Regards,

Alan.
 14 January 2018 12:54 PM
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Dave69

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When changing the panel a certificate should of been issued, how else does the customer know it has been tested and complies with what they have paid for. A question has to be asked as to why the sounders are wired in FP and the devices in normal t&e, standards require all critical wiring to be wired in either standard or enhanced fire resistant cables and this also includes the mains supply to the panel which should be provided with a double pole isolator.

As said by Alan, a conventional system has an EOL device on the last device of each circuit, both detection and sounders. This can either be a capacitor or resister and different manufacturers and even different variants of panels use different valies so they are not all interchangeable between systems.

The idea is a healthy circuit will draw a certain current, if the circuit goes open, no EOL device will be seen and the panel shows this as a fault, likewise if the cable is shorted the panel shows a fault. If a detector signals an alarm it puts a different resistance in circuit and panel knows this is an alarm and goes into fire mode.
A panel in fault mode will not sound the external sounders, it will only operate an annoying buzzer in the panel and unfortunately this can be silenced by anyone knowing the access code.
 14 January 2018 02:52 PM
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Fm

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I've inherited a few panels from a 3 letter national fire alarm panel with eol devices at the zone terminals ??
 14 January 2018 03:36 PM
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Dave69

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EOL only fitted to zone outgoing terminals of the panel if that zone is spare

Or there is a fault on the wiring and the engineer cant be ar§ed to find it and to be honest it isn't hard to narrow the fault down to a link between two devices, using a simple volt meter or even a can of smoke, although we all know finding the exact point of a cable fault can be a nightmare. Often though fire alarm wiring is put in as an afterthought meaning a fair amount of it is surface.
 14 January 2018 04:49 PM
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AJJewsbury

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Back in the days when "ordinary" cable could be used for the detectors, I thought the panels treated any short or open circuit in the detector loops as a fire condition - hence the logic for allowing non fire-proof cabling (previous to that it was typically pyro for everything).

Are we saying that modern panels don't treat shorts or breaks as a fire conduction (just a "fault"), and therefore changing the original panel to a modern one while leaving the original non-fireproof detector wiring in place has significantly degraded the overall safety of the system?

- Andy.
 14 January 2018 05:14 PM
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Dave69

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In a nut shell Andy,,,,, yes
When a panel fails to see the EOL device it treats it as a fault, it will operate a fault relay within the panel, trigger the panels internal buzzer but will not operate the external sounders. If the fault is an open circuit then any detector before the fault still stands a good chance of working, if the cable fault is a dead short then hard luck, that is why all faults must be recorded and reported immediately.

If you really wanted to, the fault relay could be wired to operate the sounders but depending on the circumstances and what the fire detection is protecting it could lead to numerous false alarms and people just ignoring an alarm. If you are in a B&B, hotel etc. do you really want the alarms to sound when a guest decides to have a crafty fag in their room and unplugs the detector
 14 January 2018 07:06 PM
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Fm

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Originally posted by: Dave69

EOL only fitted to zone outgoing terminals of the panel if that zone is spare



Or there is a fault on the wiring and the engineer cant be ar§ed to find it and to be honest it isn't hard to narrow the fault down to a link between two devices, using a simple volt meter or even a can of smoke, although we all know finding the exact point of a cable fault can be a nightmare. Often though fire alarm wiring is put in as an afterthought meaning a fair amount of it is surface.




These weren't spare zones
Just lazy engineers, I cancelled my contracts and went elsewhere
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