Isolating of Fire Panel.

[YoungBart]

Hi all, our NIC inspector came round recently, and one of the changes we had to make was to the way we 'control' fire panels. Previously we have just fed the panel from an unswitched fused spur. However according to the NICIEC man this is no longer acceptable, so what we have to do is fit a keyswitch a neon indicator and a fuse carrier into a 3g switch aparture.
The lad he told about the change is now on holiday so I can't ask him why we have to change, I assume it's simply so the panel can be switched off (using the Keyswitch), Am I right or is there more to it?

 

[myristate]

Its been this way for a while. Should be a double pole fused spur with a fishtail key switch like the ones in emergency light test keys. Also the spur should be marked as fire alarm some manufacturers don't mark them sme do, You can just label it yourself though. MK do a spur that does all of that in one. I link it below

The specs for it are here at mk K963KOALM

UPDATE:

If you want to know from the regs the specifics of what they say here is an extract:

Extract from BS5839 pt1 2002

25.2 Recommendations for mains power supplies

25.2 c) 'To facilitate local isolation during maintenance, suitable means should be provided for the double pole isolation of the low voltage supply circuit that serves the power supply and the control equipment(see 29.2e)'

29.2 Electrical safety recommendations

29.2 e) ' Means should be provided for double pole isolation of the mains supply to all parts of the system; the isolation facilities should be suitably sited , in the vicinity of the equipment served, for use by maintenance technicians without the need for access to remote parts of the building. It should be possible to lock the facilities in both the normal and isolate positions to prevent unauthorised use. See Clause 25.'

29.2 f) 'Every isolator, switch and protective device that can isolate the supply to the fire alarm system, other than the main isolator for the building, should be labelled either;
FIRE ALARM; Protective device serving only the fire alarm with no switch
FIRE ALARM, DO NOT SWITCH OFF; in the case of a switch (whether incorporating a protective device or not) that serves only the fire alarm circuit.

29.2 g) Every isolator, switch and protective device that is capable of disconnecting the mains supply to the fire alarm system should be situated in a position inaccessible to unauthorised persons or be protected against unauthorized operation by persons without a special tool

Note 4 A special tool, may for example, be a key actuator (sometimes called "secret key") for a mains switch device.

 

[Guest55]

pretty handy that MK make the exact accessory to meet the spec lol.

 

[myristate]

During commissioning of fire systems i am forever askinging the contractors who do the installation to change them over because they never fit them. A lot are unaware it is required and normally bang on just a bog standard fused spur. I normally keep that part number handy for that reason!

 

[tazz]

As above, Cragtree and a few others make the aswell, also available in Red.

 

[ian.settle1]

Hi all, our NIC inspector came round recently, and one of the changes we had to make was to the way we 'control' fire panels. Previously we have just fed the panel from an unswitched fused spur. However according to the NICIEC man this is no longer acceptable, so what we have to do is fit a keyswitch a neon indicator and a fuse carrier into a 3g switch aparture.
The lad he told about the change is now on holiday so I can't ask him why we have to change, I assume it's simply so the panel can be switched off (using the Keyswitch), Am I right or is there more to it?

Sounds like another NIC talking man through his ---- Orifice again without finding what is out there

 

[myristate]

He is correct Though for once. Not about it having to be 3G but that a normal un switched spur is no good! I can only assume your referring to the accessory fitting size! Been 3G

 

[tazz]

This became the BS reg after 2002 Ian, Phrased "Double pole switched fused spur" As you have highlighted, the NIC inspector has his terminology wrong.

 

[YoungBart]

Thanks for the help guys, I guessed it would be something to do with switching, and It makes sense really.Didn't know that there were units already made up for it though, So will certainly look at them. easier than making up the aperture as we have been doing.
Thanks again.

 

[Engineer54]

I'm not disagreeing with anything others have stated on this issue, far from it, but I did notice though that these are only recommendations from BS 5839, and not hard and fast rules!! By the way, all the projects i've been involved with have called for tamper proof double pole switching...

 

[tazz]

I'm not disagreeing with anything others have stated on this issue, far from it, but I did notice though that these are only recommendations from BS 5839, and not hard and fast rules!! By the way, all the projects i've been involved with have called for tamper proof double pole switching...

Yes it is BS5839 Part 1 reg, and is a requirement. With the idea of it being IMO semi tamper. but good enough for most installs. but if a great degree of tampler proofing is required, there would be no problem in using a double pole, fused isolator, locked off, as this would still meet requirements

 

[Robson689]

Yes it is BS5839 Part 1 reg, and is a requirement. With the idea of it being IMO semi tamper. but good enough for most installs. but if a great degree of tampler proofing is required, there would be no problem in using a double pole, fused isolator, locked off, as this would still meet requirements

Isn't BS5839 just a code of practise though (i.e. not legal document) so what E54 says about it being a recommendation strictly speaking is true

From the BSI themselves:
BS 5839-1:2013 provides recommendations for the planning, design, installation, commissioning and maintenance of fire detection and fire alarm systems in and around non-domestic buildings.

 

[tazz]

Yes as is the IEE 17th, all recommedations, but this is what we base electrical installations on
E54 has not stated he dissagrees with any of the terminology, it still stands a double pole lockable switch fused spur.

 

[chilliwilly]

Its aways been a grey area with power supplies to fire detection, despite the BS 5839 offering advice and reccomendations, and BS 7671 stating "see BS 5839 for further spec". As always drawings can't lie or be misenterpreted as can written text,.and I think drawings should be used more often to offer support to what is written down, and reduce the never ending ambiguity associated with regs. When I used to get fire alarm work, I would always install a Wylex 106 switched fuse at the mains or similar bearing the do not switch off engraved label.

About 11 years ago I installed an economy fire alarm in some bedsits in York, as the job was partly funded by a grant from the council. They offered a spec that I didn't fully agree with, they hadn't allowed for remote indication for when the rooms were locked, an interface to shut off the fans in the kitchen, along with appliances using a heat source, and the 20db+ loss rule through a fire door wasn't adhered to. I mentioned this to them before the work commenced at I was told that spec complied with BS 5839? Despite my concerns that I found whilst carrying out a fire risk assessment on the property to decide which category and type of detection to install.

Anyway I decided to do the work and listed them along with other departures they hadn't allowed for on the certificates. After the work was completed, the jerk of works who sounded like he was ex forces came round for the handover, and asked me why I had put a dp key switch next to the panel? I replied "isn't that obvious"? He then stated that if the key wasn't available no isolation could take place at that point, or there could be more than one key available to more than one person and that would contravene the procedure with locking and tagging out (food for thought). And in the event of a switched fuse spur it could be accidently switched off and the fault buzzer not taken any notice of, and an unswitched fuse spur only offered single pole isolation, and not double as required with BS5839.

He also tried to snag the fact that the pvc trunking was supporiting fire alarm cables and they could drop in the event of a fire. When I showed him that "P" clips had been used inside the trunkig as well, he backed off.

He then went on to try lecture me about isolation in general, but then said he was satisified as I had provided a supply via a lockable switched fuse at the mains in take, and the only thing that could interupt the supply to the panel was a power cut, a fault on the circuit, or someone switching off the supply to it. And so there was no need for local isolation at a single panel, as it wasn't a rotaing machine that could potentially cause amputation or worse.

Anyway I let him go on, and the job was handed over and I noted the departures on the certificates and appended their letters and spec to them, and I was paid. I mentioned it to my niccy area inspector, and he said if there had been more than one panel or other ancilliary devices or equipment connected to it, then local isolation would be required for functional switching off. So as to reduce the interuption of the supply to the panel, and rely solely on battery back up and potentially reducing the standby time afforded by the batteries. And as the power supply could be isolated and locked off at the source, it would comply to the EWAR, despite the requirement of BS 5839, and BS7671.

So it would seem from my experience with the above scenario, that local isolation isn't always necessary, except in certain circumstances?

Despite our better judgement and experience?

 

[tazz]

From your delema, this is not following regulations more than isolation. When it comes to any council or a construction company, the risk assessment, statory fire report is conducted by professionals, and goes into fire safety at a complex construction level, covering building materials etc. This field I would recommend never getting into. With councils always write on certification, "Designed to Councils Specification Doc No. or Companys Fire report Doc No.

 

[chilliwilly]

With regards to design and not isolation.

Digressing from the thread.

I know what your saying my learned friend, and I can understand why you and most other folk wouldn't get involved with fire risk assessment. But beleive me its not all smoke and mirrors if you pardon the pun, most of it is just common sense. And seeking information where its not readily available such as incipid stage, flash ignition temperatures, fire spread and passage, and other data associated with fire and combustion products.

I always conduct my own risk assessments when designing fire alarms where there is no other information known or available, and I make the person ordering the work aware that a charge will be made to visit the site, and a risk asessment will be provided in writing signed by me, along with a quote. After all if I didn't, I wouldn't know the choice of detection to select, or the class of system in general, and I certainly wouldn't use the services of any one else to carry it out, as they may overlook essential data.

In the case of a design from external consultancy based on a given risk assessment from these "professionals". I will always raise any questions or comments that I am concerned with where I feel an over sight may exist, as I do feel that they don't visit sites enough and only send out a questionaire to the person organising the work. And when they do visit sites, for them to miss a storage cupboard with combustable products stored within it and bearing the COSH and flammable liquid signs on the door. Or where the amount of detection doesn't suffice the minimum amount offered by BS 5839, or where an underdrawing/crawl space, or above a suspended ceiling, the space volume and type of contsruction qualifies for detection.

So as you can imagine, I will always enquire as to why detection or audible and visual indication hasn't been considered in these cases, or an increase in protection in the adjacent corridor or room in the case of storage. And I always note it on the installation and commisioning cert as a departure, whether they like it or not.

In the case of the council, yes they do usaully refer to some doc for design that isn't readily available to the public. But I will always question and or make them aware of fire risks or design departures that I feel they may have overlooked. And they never do like it when they see a departure on one or more certs, despite making them aware of it.

I once had an issue with a spec from AFA Minerva not allowing for enough detection on a single loop android serving 5 floors. They didn't allow for detection within the ceiling where the camera power supplies were housed and touching some kind of cork insulation, and where the bare pyro was making contact with the old burgess ceiling grid that could cause potential earth loops. Suprisingly, they agreed with me, and said it was due to the spec provided by the council much to their disagreement.

They just said continue with it and they would sort out the certification. Which were just as well as if I had of issued one with the amount of departures, it would have pulled up at some point by an official especially with it being a new job. Anyway the earth loops were apparent after they spent nearly a week trying to stop the faults appearing, and the fire prevention officer wasn't happy about the lack of coverage and the amount of sounders. And the client which was Wakefield Council (West Yorkshire Police), demanded it be sorted before payment was made.

AFA Minerva argued the point and told them their spec was not up to standard, and should consider either consulting with fire alarm companies, or employ someone who knows about fire risk assessment and fire alarms. The council ended up paying for the job to be brought up to standard and covered pyro to be used to eliminate the earth loops, and bared back where it was run down to the call points.

 

[tazz]

As I stated before, the main construction companies tend to conduct the fire stratorgy report these days, leaving the design between the archtech and us. If you are contracted by construction companies to carry out risk assessments, then thats a good string to your bow. And no daubt a good fee. After 25 years or so, I have a good relastionship with most construction companies, and if a rfi is put forward with a full explanation, they usually agreed with my cad design and changes. After all it is in their interest as well as mine to get it right. As with any project there will always be variations due to decor, and reason why detection has not been put on glass roof voids. And as you correctly state, every variation must be documented or as I like to call it Agreed Variations, were all parties are happy with the diversions from the BS