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smoke detection in lift lobbys


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I have been advised that I should install smoke detectors 1.5m from lift doors. Is this a mandatory requirement ? I already have them installed just over 2m from the lift openings so it seems a bit of excessive code hugging to BS5839. Any advice greatly appreciated.

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BS 5839 states "approximately 1.5 m" so you could push the approximately in your argument and I agree with you it is code hugging but developing a counter view is difficult.

I believe it comes from the 1980,s when they carried out research to determine, how far buoyant smoke leaking from a bedroom could travel to activate a smoke detector, in this case it is leaking from the lift shaft.

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Tom, many thanks for the reply. At least that makes me feel that I am not being unreasonable in questioning the need to have 2 detectors within a metre of each other. However, my alarm company are saying that it is a mandatory requirement or they cannot certify the system as L1. any thoughts on this or on the likely position of the enforcing authority (local FRS obviously) regarding this matter. I would have thought a degree of common sense would prevail ?

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How many lifts are in the same lobby?

When there are multiple lifts in the same lobby, an agreed variation with the interested parties can allow this distance to be modified, this is in order to reduce the quantity of detectors in the same lift lobby that might otherwise seem excessive.

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The building is a converted, large, Victorian house in use as a residential care home with 26 rooms. There are 4 floors, basement, G, 1 & 2. There is only 1 lift shaft serving G, 1st & 2nd floors. The lift lobbys on all floors are, as far as I am aware of the codes, well within the dimensions that could be covered by a single detector (10.6 x 10.6m ?). The existing detectors are approximately 2 to 2.25m from the area immediately above the lift openings. There are no protruding obstructions from the ceilings between the existing detectors and the lift so I would assume that detection of any smoke from the lift shaft would be delayed by a very marginal amount of time.

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Could they not certify the system with an agreed variation as suggested by CWEENG? You could discuss it with them or get advice from an independent fire alarm engineer.

I do not think its about the time, I think they found as the result of the research the smoke leaking from the bedroom only remained buoyant for 1.5 m and any detectors further than that did not activate. But considering all the variables I think that is why they used the word approximately.

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Thanks again Tom & CWEENG. I suppose I will have to have another chat with them but I think they will be adamant about the 1.5m and stick rigidly to what is in BS5839. I don't actually know 100% whether I even need an L1 certificate ? or whether the L1 speicification is simply guidance and best practice ? as far as I can see the L1 category calls for smoke detection in all areas including roof voids....(I never knew about the 1.5m etc) so I have always assumed that I had a defacto L1 system ? Maybe I have missed something and do have to be in possession of a certificate ? any thoughts ?

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Q Is this a newly installed system, an existing system being verified ?

Q Who selected the category for the building that then was designed?

As both a Fire System Designer and as a Fire Risk Assessor. There is a couple of key factors, and without a chat it is hard to determine. Pleas feel free to contact me direct for a chat. But with the info to date,,,,,,,,,

This topic often starts discussions and there is a couple of key points to understand and consider. Some of the misunderstanding comes from understanding of BS5839 - 1 and the cross over between the 2002 version and the 2002 version with the 2008 A2 amendments (trying not to Hug the BS and be over technical sorry).

Also what designers have been taught on Industry association design training courses.

There should be a section in all publications titled “Common sense 101”

The earlier BS highlights –

on each level, within approximately 15 mtrs of the penetration

The later version highlights-

on each level, In the Accommodation Area (A2 amendment) within approximately 15 mtrs of the penetration

To me this points the enfaces onto lifts opening onto lobbies that are also accommodation area as opposed to every level.

The wording Approximately is also used in both versions (but we could all have a view on what aprox means I am sure).

Industry training manuals and training courses also point to a degree of flexibility and the use of Variations when it comes to lift lobby devices.

To me a common sense approach would be:

  1. to have the Fire Alarm Company do there bit and certify the work to date and the system with a “Variation” (to the design or installation proposal, whichever one is appropriate), highlighting that the smoke devices is not within 1.5 mtrs from the lift doors. Assuming all else is well with the design, installation, commission and handover.
  2. As system category selection, is now very much a risk based approach, contact your local friendly neighbourhood Fire Risk Assessment Provider,

    1. to look at the situation from a fire risk angle,
    2. to look at all the factors within the premises and not just this one in isolation.
    3. Then to make a judgment call, does the fact that this device is not within 1.5 mtrs of the lift shaft pose any real significant fire risk hazard to occupant and the building.

With all other factors considered, as well as this one, is he happy that the device is not within 1.5 mtr?

Please feel free to give me a call to discus further if you wish, happy to chat.

Just my opinion,

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Thanks again Tom & CWEENG. I suppose I will have to have another chat with them but I think they will be adamant about the 1.5m and stick rigidly to what is in BS5839. I don't actually know 100% whether I even need an L1 certificate ? or whether the L1 speicification is simply guidance and best practice ? as far as I can see the L1 category calls for smoke detection in all areas including roof voids....(I never knew about the 1.5m etc) so I have always assumed that I had a defacto L1 system ? Maybe I have missed something and do have to be in possession of a certificate ? any thoughts ?

Dan I think you need some independent advise,

it is NOT the choice of the installation company what grade of system you have installed,

it is there job to design and install to the wishes of the Purchaser, ie You.

Your decision process is based on your needs and not theirs.

If you feel you do not have the necessary skills or expertise to choose then you should hav ea professional bating in your corner.

Im not saying it is the case in your situation as I do not know all the facts, but it is obviously in the commercial interest of the installing company to up sell and install the larger systems?

Even after an installation company has installed a system, and it is instilled to the correct standards with the correct certification. It is still the “Responsible Person” ie you in this case if I understand your situation correctly that is ultimatly responsible for any shortfalls in the system, if not designed to the needs of the building, the occupancy and the processes performed within.

Extract from an IFA publication for your intret,

Responsibility for Selection of System Category

Since there are eight system categories defined in BS 5839-1, a reference to BS 5839-1 without a reference to a system category, for example, in a purchase specification; enforcement notice under fire safety legislation; or a fire risk assessment would be virtually meaningless.

Within statutory requirements imposed by enforcing authorities - as part of any requirements imposed by property insurers and in any action plan of a fire risk assessment - the category of system to be installed should always be included in a specification. In addition, other than in the case of a Category M, L1, P1 and L4 system, further information needs to be included regarding the areas of the building that are to be protected by automatic fire detection. In a Category M system, there are no such areas, while all areas are protected in a Category L1 or P1 system, and only the escape routes are protected in a Category L4 system.

In particular, it should be stressed that the responsibility for determining the appropriate system category for any application does not rest with the designer of the fire alarm system, such as a fire alarm contractor, who is not expected to have sufficient expertise in the principles of fire safety to come to a decision in this respect. Although many fire alarm designers may fortuitously have such expertise, the decision rests with the fire safety specialist rather than the fire alarm system specialist.

Thus, it may be considered that there is something of a “firewall” between the role of the fire safety specialist and the fire alarm system specialist. The information that is communicated between these two parties is the system category.

Clear documentation relating to the process of selecting a system category should be compiled separate from the actual system design process.
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Thanks once again. As a retired senior fire officer I like to think that I do have a reasonable bit of experience in the business of ' fire ' . Unfortunately I never majored in Fire safety but was always Operational so the intricacies of the dark art of FS legislation were not my forte :-) . I did carry out the Fire Risk Assessment on behalf of the responsible person and I would recommend a Cat L1 (meaning to me, detection in all parts of the building) . This system is not new and was commissioned before the current owner took control but it is regularly serviced etc and appears to me in good order and it has just undergone a 6 monthly inspection. As part of the RA I advised the owner to install some additional detection in areas where previously there was none (hence my belief that it was now a defacto L1) ... the alarm servicing company beg to differ re the 1.5m issue and the fact they won't issue an L1 certificate without this upgrade. As said previously, I don't actually know if an L1 is a mandatory requirement that any enforcing authority (local FRS or CQC ) would insist on or whether it a decision for the responsible person ? As a residential care home there are no significant additional fire hazards or dangerous processes. It's basically a very large domestic premises with the same things you would find in anyones home albeit on a larger scale. The risk factor is with the residents in terms of mobility and mental capacity and evacuation, but I believe I have covered that with the emergency fire plan and staff training.

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Now a bit clearer, good.

So to be technical,,,

-Cat L2 for Residential care premises (residents capable of evacuating themselves).

--A category L2 system designed for the protection of life, which has automatic detectors installed in escape routes, rooms adjoining escape routes and high hazard rooms. In a medium sized premises (sleeping no more than ten residents) a category L2 system is ideal. These fire alarm systems are identical to an L3 system but with additional detection in an area where there is a high chance of ignition (e.g. kitchen) or where the risk to people is particularly increased (e.g. sleeping risk). And

-Cat L1 for Residential care premises (more than 10 residents above ground floor or a significant proportion of residents dependent on staff assistance for evacuation.

--A category L1 system is designed for the protection of life, which has automatic detectors installed throughout all areas of the building (including roof spaces and voids) with the aim of providing the earliest possible warning. A Category L1 system is likely to be appropriate for the majority of residential care premises. In practice, detectors should be placed in nearly all spaces and voids. With category 1 systems, the whole of a building is covered apart from minor exceptions.

From your description of the premises the selection of an L1 would sound correct. There may be Verifications and an element of L5 incorporated and this should be highlighted on the design certificate.

In relation to the actual design and the installation.

I am presuming then that the fire alarm company was instructed to up grade the system to an L1, and they should have produced a design certificate to certify there design to current BS (a G1 Certificate detailing there design and any issues arising at this stage). prior to the works taking place. Issues they had with the Lobby detectors should have been highlighted at this time and either engineered out or been a subject of a verification with the approval of interested parties (the purchaser / owner and his fire safety representatives).

Was the lobby devises part of the new installation or part of the old?

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The lobby detectors as they stand at present are part of the existing system. The reason this issue arose in the first place was my advice to the owner that an L1 was probably the correct category for his premises (borne out by your last submission)...I assumed that by installing the additional detectors in the roof voids which, during the RA I had found were uncovered, would prove to be enough for the system to be rated L1 as there would then be detection in every part of the building. The owner posed the question to his alarm company expecting to be told ' yes 'and to be issued with a certificate at a nominal cost perhaps ? The alarm company did a survey (I wasn't present) and subsequently sent the owner a quotation saying that they could not certify the premises as up to L1 standard even if they installed additional void detectors due to the lift lobby detectors being outside the 1.5m distance. So here we are with him being told that he needs the additional void detectors proposed by myself and additional detectors in the lift lobby to fall within 1.5m and then he would get his certificate but of course cost is an issue for everyone in this day and age especially if it appears OTT. I'm all about safety but also for reasonableness. I am assuming from your last piece that you believe an L1 is indeed mandatory and the enforcing authority would ask to see this certificate ? Maybe he is stumped and will have to bite the bullet and install even more detectors to fall within 1.5m of the lifts. It all seems like code hugging to me....with possibly a little bit of extra profit for the alarm company....what an old cynic I am :-) . any other thoughts CWEENG ?

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I am assuming

  • that the works have yet to take place.
  • The works required to take the system up to L1 are
    • Void detection as identified by you
    • Lobby alterations as identified by the alarm company.
    • No other works are required and no other issues exsist.

      In order to progress the project and get all the information on the table and in order to be able to take the decision on how to go forward.
      I would recommend that the client request a quotation from his alarm company and obviously another company, if not two, for comparison.

      The request to each of the companies would be:

    1. Provide a quotation for costs to design install and commission as per BS5839 along with appropriate certification, additional void detection that is required to bring the system up to L1 standard as per the finding of the recent Fire Risk Assessment.
      • Inform them, that there is split opinion for the need to relocate the detector in the lobby based on two factors
        • The Fire Risk Assessment, and
        • Interpitation of curent BS relating to detection in lift lobies.

[*]If they are of the opinion that, with their understanding of the BS that the lobby device requires relocating in order to comply, that they are to highlight this within their submission as a Variation to BS5839 for the requirements of an L1 system, and to submit the appropriate paperwork, and to provide there submission based on this.

[*]To provide a second cost for item 1 above inclusive of the Lobby device. (this so as to give all options on the table)

With all three submissions on the table with option 3 from each company if they see fit, you will be in the position to make the judgment call on the commercial aspect of the project.

From a Fire Risk Assessment point of view the decision needs to be made relating to the Lobby devise (no getting away from it)

[*]Is it acceptable in its current location and, it would not have any bearing on the safety of the building and its occupants. or

[*]Does it have to be re located.

With this approach the Technical Design issue can be separated from the Risk Based Issues.

From the previous post there is an argument from a Technical design point for the Lobby to stay as it is.

The commercial issue is that of cost, and which company to use. If they have concerns over the Lobby device they are protecting themselves by the client requesting the Variation Option 2 above and they are able to highlight this in there documentation.

The end decision can then be separated. A or B

Let me know how you get on, I would be interested on the outcome. I will send you a Pm so that you have my details.

Good Luck

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Tom and Iain, thanks for all your help with this. It amazes me that people are so generous with their time and willing to share their knowledge and experience. I don't believe that the lift lobbys pose any meaningful additional risk to the building or the people in it (the lack of roof void detection does however). After speaking to the owner, what he has decided to do is :

  • Install the additional roof void detection (plus a couple of other areas) as recommended by me in the fire risk assessment.
  • leave the lift lobbys as they currently are but...
  • next year go back and either fit additional detection here or relocate the existing detectors to meet the 1.5m distance criteria. (in effect delaying the extra capital outlay for a few months)

I will ask the alarm company if they would then be willing to certify the entire system as fully meeting L1 standard. If I get the annual visit from the local FRS Fire Safety officer in the meantime I will have to convince him/her that any perceived additional risk really is minimal and that we are working towards a total solution. What I still don't know is whether the L1 standard is actually a legal requirement for this care home or not. All I can find in the guidance are terms like " a system meeting L1 standard is probably appropriate " . It doesn't say you must have one and be able to produce a certificate to prove it and it doesn't say you mustn't ! . Call me old fashioned but I like to know where I stand and exactly what is and isn't a mandatory requirement. Either way I'll let you know if there are any other twists and turns with this one. Once again, thanks for all your help. Dan.

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Dan the only mandatory requirement is the fire safety order (RR(FS)O) the rest is recommendation, prescriptive fire safety went out with the Fire Precautions Act. However some guidance like British Standards are considered best practice and you need to be able to justify your decision if you are challenged by the FRS auditor or the courts.

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