The Law regarding Fire Alarm Systems.

[david911cockburn@btintern]

Hi All,

Does anybody know which UK Law sets out what a Fire Alarm System must achieve?

[kurnal]

The Regulatory Reform(Fire Safety) Order 2005 sets out the requirement for raising the alarm in case of fire and in some cases for the automatic detection of fire. The actual requirement will be identified by carrying out a fire risk assessment to determine the appropriate general fire precautions required to protect people from fire. This covers life safety only, not property protection. There are a number of guidance documents publisd by the Government to assist you with this, and are available for free download from the CLG website. Google CLG fire and you ill fnd them.

If installing a fire alarm system it is recommended that it should conform to best practice which in the UK is set out in the various parts of BS5839, and component parts of the system should conform to the various parts of EN54.

NB this is a summary answer only. Hope it helps.

[kurnal]

The Law does not set out what the system must achieve. Under the Fire Safety order  it must be "Suitable and Sufficient".
A shout of fire is suitable and sufficient in some circumstances. There is no legislation to say how loud someone must shout.

I think in considering legislation, you must also consider the European directives and how they are incorporated into our Laws, this can cause overlap, eg the fire alarm is required in accordance witht he H&S (Safety Signs and Signals) Regulations- is this the Legal requirement you are seeking?

Whilst the BS series are generally accepted as best practice guidance many of them contain some errors and cannot cover every situation that you may encounter.

I am interested in knowing in what area BS7671 does not comply with the EAW Regs? Always keen to learn.

[Mike Buckley]

I am afraid the Law is rather woolly and was left deliberately so. The problem with actually basing the specification of the fire alarm system in Law is the Law is difficult to change. This has a historic aspect with the Health and Safety at Work Act, prior to this all the requirements for factory safety were specified in law. However what was happening was that by the time the specifications for guarding, let us say a stamping press like Dangerous Machine Mark 1, had passed through all the legislative processes no one was making Dangerous Machine Mark 1 and it was now onto Mark 3a and the law did not apply.

How the process works is the Law refers to an appropriate alarm system which is accepted as BS 5839 and its parts. Hence most cases will be covered by a system compliant to BS5839, but there may be cases where BS 5839 is not appropriate. In these cases a solution could be agreed between the client and the enforcing authority which does not fully conform to BS 5839. On the other hand a new type of alarm system may be invented and manufactured in which case all that needs to be done is to revise BS5839 not go through the entire legislative process.

In a similar way the Highway Code is not Law, however it is used by the Courts as primary guidance as to the proper way of behaving on the road. You will not be charged with breaking the Highway Code, but you will be charged with something like Dangerous Driving and the Courts will use the Highway Code as the guide as to what is or is not Dangerous Driving.

Yes the whole thing is woolly, but that's the way the lawyers make their money.

[John Webb]

David - as someone who knows BS 7671 fairly well, in what way does it fail to match the 'Electricity at work 1989' requirements? There is a clear note from HSE on page ten of the 2008 edition of BS 7671 that installations carried out to BS 7671 "are regarded by HSE as likely to achieve conformity with the relevent parts of of the Electricity at Work Regulations...."

BS 5839 is not based on legal requirements - it was developed by the trade and users from a previous Code of Practice (CP1019, I think) as setting out reasonable requirements for a viable fire alarm system which matches the needs of particular premises. Fire safety legislation then refers to the BS as a guide for those wishing to install a system.

But as Kurnal points out, the type of fire alarm needed in a particular premises is dependent on a risk assessment. For example, a number of the extremely elderly church buildings I give advice to the risk assessment will probably recommend a set procedure for clearing the small congregation from such a building without any recourse to a fixed electrical system which they may not be able to afford and maintain and whose installation would be detrimental to the ancient fabric of the building.

[kurnal]

Not quite clear what you are saying. Please feel free to email your documents- the address is shown at the bottom of my postings.

I might be being thick here but in your previous posting I think you are suggesting that all flexible leads that may be plugged into a supply should incorporate an earth conductor irrespective of whether the appliance supplied has some other conductor or surface that that could become charged and live as a result of a  fault condition? Is this what you suggest or have I got it wrong?

If the appliance is double insulated then the provision of an earthing conductor in the cable would only be a safeguard if the live and earth were simultaneously exposed, it would not help if I nicked the cable and only exposed the live conductor?  

Your last posting seems to discuss fire alarms and mains wiring  and sorry but it has left me completely confused. We do not have mains powered fire alarms any more.

[John Webb]

David,

I think I see what you are driving at but if any manufacturer claims that 'air' forms part of the double insulation of any portable equipment then I think their equipment is wrongly labelled as being 'double insulated' and this is a matter for trading standards and the like. All double insulated equipment I've ever pulled to pieces has always had two separate lots of insulation.

I'm not too clear about the 'EAWR' business, not having, I admit, read these in detail. But I assume the reference to 'conductors' is what Part 2 'Definitions' of BS7671 (page 24 in the 2008 edition) calls 'extraneous-conductive-part' and which does not form part of the actual installation? In which case BS7671 does deal with the need to earth these in Section 4 Chapter 41 or gives circumstances where it is not necessary to do so. So it is possibly the sort of case that is mentioned above by Mike Buckley where detailed legislative requirements have not kept up with technical developments.

[Wiz]

I'm also confused by this thread and how it applies to the sort of fire alarm systems we use today.

Normally the only mains voltage connection to a system is via the cie (control and indicating equipment)

The cie also requires an earth connection and any metalwork used in the cie (including a hinged door) is connect to this earth.

The fire alarm circuits cables, which are generally only carrying extra-low voltages i.e 24V dc, need to enter the cie through a different access point from the mains supply and these cables invariably also contain an earth conductor which is also connected to the cie earth.

Most fire alarm accessory equipment housings are made of plastic, with the exception of fire alarm bells, and all of these items normally have an earth connection.

Whilst it is true to say that there is some danger from electrical shock because BS does not recommend the use of of a residual current prtotective device (other than where it is necessary to comply with BS7671) the whole system is pretty comprehensively earthed, and I've never heard of any problems with modern systems relating to electric shocks from the equipment.

[Wiz]

Hi David,
We already know that the precise requirements for fire alarm systems are not enshrined in some sort of water-tight set of laws. Even the recommendations are often open for interpretation. We have lived with it for years and can't begin to worry about it any more than we ever have done.
As for the electricians, I can't see their trade bodies allowing them to be held liable for anything that was standard and accepted practice in the past. If some supposed future allocation of 'blame' is something that potentially affects a large number of business people, then politicians will have to do something about it or face the wrath of these people.
You can rest assured that if there is any cost to be paid by anyone for something the politicians have missed in the past, it will be paid for by the general public, directly or indirectly. Business might have to administer it, but they will not lose any money over doing so. This is the way of the world in the UK.

[CivvyFSO]

There are really two separate issues here. One is the requirement to provide a fire alarm, and the other is electrical safety. Both covered by legislation, and both quite separate. Your beef is clearly with the BS7671, which is referenced within BS5839.

At the risk of sounding flippant, if someone was electrocuted by a fire alarm it is not a fire safety problem. The HSE would investigate, not us.

[kurnal]

I have received Davids papers and am happy to forward them to anyone who asks. The files are too big to attach, and I do not have a picturebox account or similar application to link to, if anyone else has such an account I or David will forward the files.

I thought the screen was earthed in a FP200 or MI cable attached to a fire alarm system?

(I only drive them I dont fix them)

[Wiz]

David,
I think I have got some basic idea, after 30 years in the business, about the need for earthing for electrical safety reasons.

For your information, the fire alarm cie requirement is for the metal door or cover to be properly earthed by flexible wiring that goes between the mains incoming earth and that door or cover. It doesn't just rely on a conductive path through a hinge or similar.

Of course organisations will automatically put a disclaimer with any information they produce. This is mainly to cover themselves in respect of errors in information obviously beyond their control. But they can't discard responsibility for absolutely everything with a simple disclaimer, there are certain responsibilites that everyone automatically has.

However, electricians have trade support organisations whose role is to uphold standards, and to inform and train their member  If every electrician is doing the same thing based on good practice and advice (even with a disclaimer) then I can't see the whole industry not coming behind and supporting any of them being punished in the future for something they all do and believe is correct.

Furthermore, there is nothing you have mentioned that makes me believe that fire alarm equipment or installations are affected by the problem you have raised. It is a fixed installation with proper earthing, and the problem you have raised seems to be with portable equipment with unearthed electrically conductive surfaces that may be powered from a supply without using an earth. What has that got to do with fixed fire alarm installations?

I don't believe that fire alarm system companies / designers / installers have anything to worry about in respect of your fears.

[Wiz]

Hi All,
The reason that very little has happened up to this point within the Electrical Industry is because until recently the authorities (including the NHS and the Police) did not recognise the difference between RCD's and MCB's.
If you imagine the difference between cooking in an oven and cooking in a microwave it is easiest to understand, a circuit protected by an RCD 'cooks' its' victim from the inside like a microwave whereas a circuit protected by an MCB or a fuse also leaves the victim 'crispy' on the outside.

Heart attacks are on the increase, but even if the victim survives why would they think that electrocution had been the cause when they had only leant on an innocuous looking radiator?

Now I am worried.

RCD's 'cook' a victim!

MCB's make them crispy!

Medical experts can't recognise electric shock victims!

Prof. K. sort this out! I'm now leaving the building!
 
Matron! Call 911!

[kurnal]

Sorry if I took this thread off at a tangent. Back to the original question David I would summarise the consensus as follows:

The legal requirement to provide a means of warning in case of fire is a functional rather than a technical one.
For existing buildings the Fire Safety Order places a duty on the Responsible Person to carry out a fire risk assessment in order to determine a suitable and sufficient solution.

For new buildings and alterations to existing buildings the Building Regulations require the developer to make provision for warning and in some circumstances detection of fire.

 In both cases if you choose an electrical alarm system to fulfil this requirement then  a system designed, installed and maintained in accordance with BS5839 will represent an acceptable solution. However you are not bound to follow this guidance and are free to install whatever system you choose.

If you choose not to follow the guidance and are considered to be in breach of the Fire Safety Order and are charged with an offence which leads to court, the burden of proof falls on the responsible person to prove to the court that their solution provides an equivalent standard of life safety. Similarly for new buildings Approved Document B lists BS5839 as an acceptable solution you have freedom to do something else provided you can convince the Building Authority that your solution is equivalent.

In both cases there are provisions for determination on the technical solution by the Secretary of State.

Hope this helps David, please anybody feel free to modify any of the above if I have not expressed the situation accurately.

[kurnal]

David I am sure there are many  here able to answer you but I wondered if you are also aware of another forum

http://firealarmengineers.com/forum/

You may find answers there too.