L5 Variation

[Tommy]

Hi All, I am currently completing a job which the scope of works was vague to say the least. I am producing documentation after the fact so its getting a bit complicated.
I have to complete a design certificate which asks for the category and the category was L5 although not specified in the scope. What should i put on the certificate regarding variations for a L5 system.
In reality most areas are very well protected and could list it as L3 but client want to cover his bum. But so do i. Should i ask him for his Fire Risk Assessment before completing the Design Cert and list it on the reference documents. Should i also list the scope of works on the certificate as the scope did not allow for additional detection in some areas that were known to be lacking?

Any help folks would be great. 

[AnthonyB]

L5 is a vague term in itself as it could be anything from a single head in an access room to a very complex system that for a specific life risk based purpose doesn't fall into one of the above categories.

"Category L5: systems in which the protected area(s) and/or the location of detectors is designed to satisfy a specific fire safety objective"

I would therefore expect any certification to L5 to include reference to the location and risk specific purpose of installation. If heads are located as per the design spec & FRA and other elements comply with BS5839 I don't see any variations to list.

It sounds like the system you describe isn't a true L5 system at all, but an L3 with variations i.e. the designer forgot to include a couple of heads to make it compliant.

I've seen L5 used on systems that weren't designed to satisfy a specific fire safety objective, but instead were meant to be L4/3 but with mistakes/omissions in the design and install.

[colin todd]

Thomas, the L5 designation relates only to the areas protected.  All the rest of the code applies, so you need to list variations from these clauses if there are any.  I would counsel that you do not get involved in the FRA.  If someone told you where to put the detectors and claims that it is L5, then so long as they told you where to put them, L5 it is, and I would certificate it as such.

[Tommy]

Thanks Chaps, Yes we were told where to put the detectors in a design brief. i.e replace existing conventional detectors with new Addressable detectors but some areas are still not Compliant with an M type system. There are massive search distances of over 90m and some exits do not have MCP's at them. So even though it is L5 it is still not compliant with the most basic system. Would i be correct in listing these as Variations on our design certificate and carrying these through to the commissiong certificate. I am trying to do the whole process as Listed in BS-5839-1 i.e 1) Design Cert 2) INstallation Cert 3) Commissioning Certificate and hopefullt an Acceptance Certificate all complete for this Job as it is a job that may helkp us get the 1014 certification.

[AnthonyB]

Why replace a whole system (not cheap), but other than new devices still leave it as non compliant and potentially not 'suitable & sufficient'? Pointless other than making someone some money!

It sounds totally non compliant so I wouldn't certify it as being in any shape or form - if even the basic M category requirements are not met what hope is there?

Commission & document it as a non conforming system listing all the variations & cover your backside!

I know of one case we dealt with years ago acting for the premises owner where a non compliant system was installed but certified as being both to BS5839 & L1 which resulted in the parties involved in the design and install having to foot the bill to rip it out and put a whole new correct system in. If it doesn't meet the standard don't say it does!

[colin todd]

Thomas you dont need to comply with Cat M in a Cat L5 system.  I would just put any variations from other clauses in the design cert. You then dont need to carry them forward to other certs as the variations in these certs relate only to variations from th spec (there arent any) and variations from the installation section or clause 39 on commissioning, which there need not be.

[Wiz]

IMO a fire alarm commissioning system does not necessarily cover the whole of the system/building. The BS model certificate has the following phrase included ' The extent of the liability of the signatory is limited to the systems described below'  then there is a space to describe such with the heading; 'Extent of system covered by this certificate'

[Tommy]

My Belief is that a system can be certified based on a Scope of works / Risk assement as requested by the client. Therefore i can certify my Design cert, INstallation cert and commissioning cert based on their document. The Extent of the system will then be based on my as built drawings and my device list showing all the locations covered. I think this would comply with the L5 System as per BS5839-1.

[kurnal]

Yes but someone should be pointing out to the client the weaknesses of his existing system. And in an auditable way even if recording variations on a system certificate is not relevant.  He is paying for the services of an expert contractor and in my view we should not take a blinkered approach.

He may not understand the implications of the variations from best practice. Like the owner of the 3 storey victorian care home I visited recently who had never been told by any service engineer he had paid for over 20 years that he only had a single sounder circuit. I think that is a disgrace.

[colin todd]

What is the risk Big Al of the single sounder circuit, bearing in mind that the 2nd cct needs only a single sounder.  Hardly a disgrace.  Indeed, hardly matters in all probability.

[kurnal]

The disgrace is that it is a significant non compliance with the code that should have been brought to the attention of the rp by the myriad of fire alarm engineers who have serviced the system over a generation. But clearly they either did not observe the issue or decided it was not sufficiently significant to merit comment.

I am surprised you think it hardly matters though, and prompts me to ask why the  recommendation is included in the BS if this is the case?

My point is that if I pay an expert to perform a service for me I would expect to be briefed on those matters that as an RP I would not be likely to recognise myself. There are many other common examples such as sounders wired in pvc, door hold open devices wired to the sounder circuits, emergency lighting not configured to sub circuit failure.   

[Tommy]

I worked for a company a few years back and when I asked the question as to why we were designing systems without taking the 2nd sounder cct into considderation, i was told that if the system was addressable i.e a loop, then if the circuit was split in two that you would essentially have 2 sounder circuits. I suppose it gets around it in a way but not sure what the fire officer would think of their logic. Also what if the system is a networked system, would 1 sounder circuit on each panel be sufficient as they are both part of the same system. 

[Wiz]

The disgrace is that it is a significant non compliance with the code that should have been brought to the attention of the rp by the myriad of fire alarm engineers who have serviced the system over a generation. But clearly they either did not observe the issue or decided it was not sufficiently significant to merit comment.

I am surprised you think it hardly matters though, and prompts me to ask why the  recommendation is included in the BS if this is the case?

My point is that if I pay an expert to perform a service for me I would expect to be briefed on those matters that as an RP I would not be likely to recognise myself. There are many other common examples such as sounders wired in pvc, door hold open devices wired to the sounder circuits, emergency lighting not configured to sub circuit failure.   

Prof., the owner only said he hadn't been told. Maybe it was easier to tell you this than ' I was told about this years ago, but decided to ignore it'!

[Wiz]

I worked for a company a few years back and when I asked the question as to why we were designing systems without taking the 2nd sounder cct into considderation, i was told that if the system was addressable i.e a loop, then if the circuit was split in two that you would essentially have 2 sounder circuits. I suppose it gets around it in a way but not sure what the fire officer would think of their logic. Also what if the system is a networked system, would 1 sounder circuit on each panel be sufficient as they are both part of the same system. 

What does it matter what the fire officer thinks if the system is compliant with the current BS5839-1!

If you comply with BS5839-1 when designing your addressable system your sounder queries are covered. The recommendation for short-circuit isolators cover your loop sounder question. The recommendations for monitoring and integrity of network connection cables cover the second question.

The point Mr Todd is making in his post above is that the BS recommendations for at least two sounder circuits are not based on the likelihood of the sounders failing before the premises is evacuated, but on the danger of people re-entering an unsafe building, if the sounders suddenly stop working.

[kurnal]

Prof., the owner only said he hadn't been told. Maybe it was easier to tell you this than ' I was told about this years ago, but decided to ignore it'!

Thanks Wiz and you make a fair point over the purpose of the dual circuits. In this case the owner has a full set of bills invoices and reports dating back to when the old Firedex 1000 was installed so I can confirm he has never been told in writing. Actually thinking about it, the installation probably predates the 88 standard so that may be a part of the explanation. Numerous original detectors remain as well.