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FIRE SAFETY => Fire Alarm Systems => Topic started by: Tom Sutton on September 28, 2011, 02:55:18 PM
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Is installing a BS 5839 part 6 system (Grade D) in a small office building, two storeys, three offices on the ground floor two on the first acceptable in these days of risk assessment?
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Is installing a BS 5839 part 6 system (Grade D) in a small office building, two storeys, three offices on the ground floor two on the first acceptable in these days of risk assessment?
No. But strangely enough they can be OK in a small guest house of greater risk.
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It might be ok in some limited circumstances - but how would staff discovering a fire raise the alarm? Would you need a gong as well as the smoke alarms? That would be far from ideal. And a small part 1 system may well be no more expensive than interlinked domestics.
I usually only recommend a part 6 system in a workplace in very limited circumstances, eg to cover inner room situations or where rooms may be unstaffed and a fire might develop cutting off the means of escape from occupied areas.
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The legislation says a suitable means of giving warning, sufficient detectors and alarms etc.
However, the CLG guidance states:
New automatic fire detection systems should be designed and installed by a competent person. Further guidance is given in BS 5839-1
A better option might be one of the grade C systems knocking around, interconnected detectors and they have also have call points with some rudimentary test/control/silence facilities on them. One of these, accompanied by a similar test regime to a part 1 system, and you are not too far away in my opinion.
There will be people who disagree with this, so you are unlikely to get a solid answer and it will ultimately be down to an assessment of risk by the assessor or RP. It would certainly be worth asking the opinion of the local FRS. They may not want to take the responsibility for saying a part 6 is ok, but what you need to know is whether they would enforce the change up to a part 1 even if the risk assessment took it into account and the RP took the responsibility.
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Pt 6 for access rooms, yes, anything else, not ideal.
If it was going to OK such an install it would have to be Grade C, include call points, not be high risk occupancy or fire risk (unprotected cabling) and of course less than the single zone limits in Part 1. I'd want the Part 1 audibility levels as well which would mean loads and loads of smoke alarms if not open plan far above the category probably needed
You might as well put an L5 conventional in really as with just the manual cover plus risk specific detection only (if any) as costs would be similar but with no grey areas.
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Surely (and without knowing the building) that it would be an L4 as a minimum to cover to exit from the first floor to the ground floor and subsequent exit + M?
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As Civvy says " a suitable means of giving warning".
Only the FRA will identify what that is. The benchmark guidance for an occupied workplace is a part 1 M system and we usually build from there depending on the fire risk assessment.
The problem is the segregation of fire alarms into part 6- residential/domestic and part 1 - all other occupancies and nere the twain shall meet. Cross the demarcation line at your peril.
It might be more helpful if the transition were seamless - if part 1 and part 6 were actually in a performance based single standard covering the provision of alarms from the shout of fire through to the L1/P1 standard, and where the provision is actually based on risk.
As Nearlythere succintly points out is it a bit of a nonsense to get into heated discussions over the sin of installing a part 6 system in a low risk office where everyone is awake and familiar with the building whereas the sleeping guide points people towards part 6 systems in many guest houses in which people, unamiliar with the premises and probably under the influence are fast asleep? (and then misrepresents BS5839 as it does so)
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I enjoy a heated discussion.
5839 Part 6: Code of practice for the design, installation and maintenance of fire detection and fire alarm systems in dwellings .
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So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??
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So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??
That appears to be a control measure for an inner room condition Allen. In my time in the FS it was an acceptable way of providing the automatic early warning but that was a time before detection flooding became common, even when it isn't necessary.
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So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??
Yeah, confusing innit! There are any number of recommendations, advice, opinions and rules of thumb in the fire alarm game. Many of them seemingly contradictory. It also seems that anyone can suggest their own ideas and have it thought as relevant. No wonder it is often difficult to know what to do. No wonder so many people get it 'wrong'!
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If a commercial premises require an electrical fire alarm then cat M is the first consideration followed by the necessary cat if automatic detection is required, all part 1. As for access rooms consider vision panels first or the partition is short of the ceiling, however if detection is the preferred option then connect into the cat M system. Use part 6 for domestic or similar type of premises, like small B+B much less confusion.
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So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??
It fits because it is used in the worked example FRA in the DCLG entry level guide based on a two room lock up shop - the 'solution' for the inner room (office/store) is a smoke alarm (not smoke detector) in the access room, manual warning being in the form of a shout of fire and EL a couple of torches.
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So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??
It fits because it is used in the worked example FRA in the DCLG entry level guide based on a two room lock up shop - the 'solution' for the inner room (office/store) is a smoke alarm (not smoke detector) in the access room, manual warning being in the form of a shout of fire and EL a couple of torches.
Thanks for clearing that up Anthony - one less thing for the anorak in me to get worked up about!
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Right. How about another spanner in the works.
Fire risk assessment is all about taking reasonably practicable measures to reduce the level of risk in existing buildings. The smoke alarm achieves this perfectly in the example of the petrol station shop.
But if I was designing a new petrol station shop with an inner room and submitting the design for Building Regulations approval is it reasonable then to incorporate a domestic type smoke alarm? Or do we think the BCO should reject the design?
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Right. How about another spanner in the works.
Fire risk assessment is all about taking reasonably practicable measures to reduce the level of risk in existing buildings. The smoke alarm achieves this perfectly in the example of the petrol station shop.
But if I was designing a new petrol station shop with an inner room and submitting the design for Building Regulations approval is it reasonable then to incorporate a domestic type smoke alarm? Or do we think the BCO should reject the design?
From what I can make out at the moment Kurnal Building Control consider a means of giving warning in the event of a fire as a full fire alarm system to BS5839 regardless of the size, layout or use of the building. I have also seen a single prefab unit with a full electrical system with manual and auto operating points.
I was at a 12 year old stable block yesterday after one of Yorkshire's best fire extinguisher suppliers was trying to fleece one of my countrymenpersons out of £500 for two extinguishers. This was a straighforward, simple, everywhere in view from anywhere situation and BC made her install a full system.
So I really think that the domestic detector in inner room condition in new build may not arise.
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Do you think Joe public thinks a fire alarm is a full AFD system and maybe some fire risk assessors? At one time AFD was a rarity except in sleeping risks.
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Do you think Joe public thinks a fire alarm is a full AFD system and maybe some fire risk assessors? At one time AFD was a rarity except in sleeping risks.
Absolutely. And many building owners also.
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And many electicians who install fire alarms. Like the one who told me that " the Law says any workplace with more than 5 staff must have at least an L3 system. No choice. Its what the Law says."
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Right. How about another spanner in the works.
Fire risk assessment is all about taking reasonably practicable measures to reduce the level of risk in existing buildings. The smoke alarm achieves this perfectly in the example of the petrol station shop.
But if I was designing a new petrol station shop with an inner room and submitting the design for Building Regulations approval is it reasonable then to incorporate a domestic type smoke alarm? Or do we think the BCO should reject the design?
The diffenence is surely that the fire risk assessment is carried out under the Fire Safety Order and the BCO is concerned with the Building Regs and his benchmark standard would be ADB - Building's Other Than Dwellings, so would be under no obligation to accept a smoke detector for a dwelling.
While you can argue that satisfactory means of escape in a building should be the same in a new build as an existing building, but doesn't 'reasonable practicable' change: Just had a quick look, and new petrol stations cost between £500k and £1.2M, it could be argued that the cost in terms of 'trouble time and money' of a fire alarm to cover this risk may be less interms of the cost of the new build, but could be more in terms of whatever business is occupying an old building that never had an Fire Alarm (say it's an independant seller, their only premises) - therefore not reasonably practicable to control the risk by installing a full alarm and AFD to cover the inner room in an existing building, but a domestic detector is?
As one of my old bosses used to say: is a FRA not comparable to a car's MOT? The MOT standard is one that you shouldn't let your car fall below, but you'd never build a new one to MOT standards?
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Right. How about another spanner in the works.
Fire risk assessment is all about taking reasonably practicable measures to reduce the level of risk in existing buildings. The smoke alarm achieves this perfectly in the example of the petrol station shop.
But if I was designing a new petrol station shop with an inner room and submitting the design for Building Regulations approval is it reasonable then to incorporate a domestic type smoke alarm? Or do we think the BCO should reject the design?
As one of my old bosses used to say: is a FRA not comparable to a car's MOT? The MOT standard is one that you shouldn't let your car fall below, but you'd never build a new one to MOT standards?
You would. The MOT is a safety not a style issue. A vehicle has to be safe on the roads regardless of the age and any road vehicle has to meet a minimum standard of safety set down in guidance. A new flash car like yours Northy may be able to stop from 60 mph within 20M whereas my more mature jaloppy would take 40. But does that mean I have to take my passion wagon off the road because yours can stop sooner than mine.
I keep getting the feeling that in many cases fire alarm systems are installed in premises because someone, including BC and F&RS IOs, thinks there has to be one installed without taking into consideration the size, layout and use. That to me is style policing.
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And many electicians who install fire alarms. Like the one who told me that " the Law says any workplace with more than 5 staff must have at least an L3 system. No choice. Its what the Law says."
Was the lawman in this case John Wayne, Prof.? Or some other cowboy?
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By defintion, smoke alarms in a workplace cannot be claimed to comply with BS 5839-6, because it is outside scope of Part 6. That does not mean it can nver ever ever be ok, just that it will not comply with any standard.
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If ADB & BS5839 was followed as it is printed a lot of buildings would still have Category M systems with detection only P1 or P2 if the insurers or client wanted property protection.
Yet it seems to be the done thing for L1 to go in every new build and for full AFD on any floor refurb that requires BCO approval.
Millions will have been spent over the years on over provision, risk assessment or not, mainly because no-one dares challenge the status quo presumably down to cost and not wanting the BCO to have a chip on their shoulder for future projects.
It's very rare for me to require L1 in an FRA, yet I doubt I've put any lives at risk!
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Yet it seems to be the done thing for L1 to go in every new build and for full AFD on any floor refurb that requires BCO approval.
Millions will have been spent over the years on over provision, risk assessment or not, mainly because no-one dares challenge the status quo presumably down to cost and not wanting the BCO to have a chip on their shoulder for future projects.
A lot of what goes into buildings are part of a specification that goes into a contract with the end user and goes outside of the scope of the BCO, (particularly with local authority buildings). I've just dealt with one office which had large roof spaces, and the M&E contractor wanted to remove the void detection, as providing it would require gantry access etc and would cost the contractor thousands, which was fine with me as the existing arrangements were an over-provision for BR purposes (an L3 would have been fine). But the contract stated an L1 system must be provided, so it's followed as they don't want to get into difficulties when the 5839 cert is handed over.
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It sounds like those drawing up the contracts as part of the design either over spec to cover their backsides, or just don't know!
Obviously the install company have to follow the spec, it's just where on earth it comes from (like full common systems in purpose built flats)
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It sounds like those drawing up the contracts as part of the design either over spec to cover their backsides, or just don't know!
Obviously the install company have to follow the spec, it's just where on earth it comes from (like full common systems in purpose built flats)
My theory AB is that architects just whack it in to be sure.
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I enjoy a heated discussion.
5839 Part 6: Code of practice for the design, installation and maintenance of fire detection and fire alarm systems in dwellings .
Hit the nail on the head with that one, Wiz.
Anything further than this and you are looking at a category of system within Part 1.
Small single story buildings aside, Is there any point in making it less black and white than this?
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Small single story buildings aside, Is there any point in making it less black and white than this?
Hardly black and white if you consider it suitable for a small commercial premises is it? :)
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I enjoy a heated discussion.
5839 Part 6: Code of practice for the design, installation and maintenance of fire detection and fire alarm systems in dwellings .
Hit the nail on the head with that one, Wiz.
Anything further than this and you are looking at a category of system within Part 1.
Small single story buildings aside, Is there any point in making it less black and white than this?
Assured. I can see your interest in pressing the guide which states the recommendation for Pt1. I had recently asked a Fire Alarm engineer to provide a quote for a small first floor dental surgery with inner rooms. I had asked him to quote for a L5 detection system due to the inner room conditions only with a manual call point at the head of the stairway. There is no communication between the ground floor and the stairway which is concrete.
The building is in multi ownership with each owner occupying each floor so a building common system is another issue.
The spark came up with a quote for around £2000 for providing afd in every room and two call points in the stairway, top and bottom.
Asking him why he proposes this level of cover he said that the BS says so. It was also apparent that he had no idea, or maybe didn't want to know, of any category other than 1 & 2.
The front of my head was bleeding for days due to the wall.
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But who was designing the system N.T., you or the fire alarm engineer?
It is not the system installer's or commissioner's job to question the design.
The designer produces certification to state that his design complies. The design is the designer's responsibility.
The installer or commissioner can't be held responsible for any mistakes made by the system designer.
Whilst it is true to say that there is a BS recommendation for installers to liase with the designer over things he might not have known about at the design stage, once he has agreement from the designer that he has taken that 'thing' into consideration within his design, then there is nothing more he needs to concern himself about it.
Some installers/commissioners are either just to stupid to understand what their role is, or they are just trying to 'bump' up the value of the job!
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Was he a genuine fire alarm engineer or just a spark?
It is possible to be both, but some of the latter do have a funny idea about the installation of systems and BS5839 & risk assessment.
If they don't understand the spec they don't get the job - suggestions about minor amendments will be taken on board but if they tried that line with me they would be out of the door.
Far too often sadly clients only refer to their external consultants for the FRA and rely solely on the provider/installer to guide them when implementing action plans often resulting in either gross over-provison or non compliant jobs.
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But who was designing the system N.T., you or the fire alarm engineer?
It is not the system installer's or commissioner's job to question the design.
The designer produces certification to state that his design complies. The design is the designer's responsibility.
The installer or commissioner can't be held responsible for any mistakes made by the system designer.
Whilst it is true to say that there is a BS recommendation for installers to liase with the designer over things he might not have known about at the design stage, once he has agreement from the designer that he has taken that 'thing' into consideration within his design, then there is nothing more he needs to concern himself about it.
Some installers/commissioners are either just to stupid to understand what their role is, or they are just trying to 'bump' up the value of the job!
You're right Wiz. I am the designer but I was expecting a llittle savy from the installer especially when I explained the reason for the L5 system. Obviously, he has trouble understanding the rational behind L4 & L5 systems.
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But who was designing the system N.T., you or the fire alarm engineer?
It is not the system installer's or commissioner's job to question the design.
The designer produces certification to state that his design complies. The design is the designer's responsibility.
The installer or commissioner can't be held responsible for any mistakes made by the system designer.
Whilst it is true to say that there is a BS recommendation for installers to liase with the designer over things he might not have known about at the design stage, once he has agreement from the designer that he has taken that 'thing' into consideration within his design, then there is nothing more he needs to concern himself about it.
Some installers/commissioners are either just to stupid to understand what their role is, or they are just trying to 'bump' up the value of the job!
You're right Wiz. I am the designer but I was expecting a llittle savy from the installer especially when I explained the reason for the L5 system. Obviously, he has trouble understanding the rational behind L4 & L5 systems.
The installer doesn't really need to understand the rationale of a design.
He should just get on with installing it!
Obviously it would help if he understood the BS5839-1 recommendations for installation but if he can't do what he is told to do, then get a new installer!
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For me theres two different topics here.
The first is Part 1 vs Part 6 - which i think is pretty black and white. You are given a 'menu' of design categories (and in the latter case, a grade also) to choose from menu style, and i cant see why it has to be anymore complex than this? Pick one, and work to one or the other depending on if the property is a dwelling or not.
This slightly leads on to topic two - Potentially if its a part 1 system, i could understand this becoming a little more obscure if an L5 system is specified - however, the selection of L1 to L4 (from the 'menu') should be decdied upon a Risk Assessment just as much as an L5 in which case some specific guidlines as to what the objective of the L5 system should be given. (Whats to be protected and how to do it, or if the system is an engineering solution).
Whomever needs to design/install the system, can then do-so accordingly.
Before anyone says, this is all very idealistic i know and appreciate...
I do throw out a question to everyone though - Is it just me or do very few risk assessments actually conclude a design category? Very few and far between from what i have seen.
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For me theres two different topics here.
The first is Part 1 vs Part 6 - which i think is pretty black and white. You are given a 'menu' of design categories (and in the latter case, a grade also) to choose from menu style, and i cant see why it has to be anymore complex than this? Pick one, and work to one or the other depending on if the property is a dwelling or not.
This slightly leads on to topic two - Potentially if its a part 1 system, i could understand this becoming a little more obscure if an L5 system is specified - however, the selection of L1 to L4 (from the 'menu') should be decdied upon a Risk Assessment just as much as an L5 in which case some specific guidlines as to what the objective of the L5 system should be given. (Whats to be protected and how to do it, or if the system is an engineering solution).
Whomever needs to design/install the system, can then do-so accordingly.
Before anyone says, this is all very idealistic i know and appreciate...
I do throw out a question to everyone though - Is it just me or do very few risk assessments actually conclude a design category? Very few and far between from what i have seen.
It should specify the category Assured. Same way as you specifying a class of extinguisher for a particular risk.