Strange fire alarm system in the New Year 2008 ???

[Benzerari]

The commentary in BS5839 part 6 2004 describes a grade C system thus
" A system of fire detectors and alarm sounders (which may be combined in the form of smoke alarms) connected to a common power supply, comprising the normal mains and a standby supply, with central control equipment"

Grade A,B,C systems all have a degree of monitoring - Grade A control and monitoring equipment refers back to BS5839 part 1, grade B monitoring is as per Annex C of BS5839 part 6, whereas there are specific requirements for some monitoring of Grade C systems, these are
- an open circuit or short circuit in any circuit external to the panel serving MCPs, fire detectors or alarm devices this should result in a visual indication at the control panel or a fire alarm system in the dwelling within 100 secs of occurrence and
- a power failure shuld result in a visual indication at the control panel within 30 mins which may be a normally illuminated indicator being extinguished or a fault lamp being lit.

This clause more than any other highlights a major difference between a grade C system under part 6 and a Part 1 system.
Hope this explanation helps - but if you have any technical question I would ask our friend Dr Wiz. He should be free very soon- I can hear Matron coming.

Thanks for these details Kurnal;

What you have stated about Grade C aren't they in conventional and analogue addressable systems aspects too?
Sorry if I am a bit slow in understanding interpretations of the standards and legislations, but I just need a clair confirmation that the Grade C systems are not the conventional and analogue addressable systems we deal with on every day basis...

All I have seen up till know and every where is conventionals and analogue addressable systems in addition to very old smoke detectors powered with both batteries and mains kind of systems. a part from that where are they fitted Grade C then? and how they look like any example of a make in the marketplace?

[kurnal]

I have never seen a grade C system and I dont know of any guidance that recommends them- usually the guidance either recommends a grade A system for larger high risk premises or Grade D elsewhere.
I guess their limited use will make them uneconomic to produce.

The monitoring requirements for Part 1 systems are far more rigorous than those for a grade C system. The list in my earlier posting is the total requirement for monitoring on a grade C system whereas  Part 1 systems also monitor for earth faults, removal of heads etc etc.  The conventional and analogue systems you see every day  will be to part 1- a much higher spec.

[Graeme]

Benzerari,
Take a bit of advice from someone who has been doing this for 30 years, and also deals with local authority customers:-
Advise your customers of any defficiences in writing and basically leave it at that. Don't try to 'encourage' them to spend any money at this stage by immediately looking for pieces of legislation etc. that support your case. They will think you are trying to force them into spending money and, anyway, they should be aware of any legislation. They are responsible.

If they query your findings, then quote the  B. S. recommendations that are applicable.

If they ask what the ramifications will be if they don't rectify the deficiences, then also quote any legislation that is applicable.

They are likely to carry on using you as a contractor because you haven't 'badgered' them.

If they don't rectify the problems you are covered against any comebacks.

If they decide to rectify the problems you are in a position to quote for the work.

that's very good advice Benzerari from Wiz.

it's a no win situation as the more you try to point out the flaws the more you alienate your customer.The last thing someone wants to hear is their system is rubbish because that equals money.

If someone has accepted a 240v system as fine then good luck to them.This is the very thing i wrote about a while ago when recommending works on sites with sub standard very old systems,only for someone else non technical to tell the customer it is okay.
The customer will take that word over anyone elses as it costs the least.

As long as you have pointed out all you find,then your covered and the comeback is on the one who said it is fine.

[Benzerari]

Right; this topic has given me ( including others ) more than I was expecting, however, since I launched the free MCB01 training software, roughly 1500 downloads been carried out and none of the members who downloaded and run the software tried to ask: ' that's conventional fire alarm system it is not Grade C system ' ... because in the first form when opening the software it shows:

            ‘Learning the basics of fire alarm systems of (Grade C) just by the click of mouse’

In fact then it should be simply as follows:

            ‘Learning the basics of fire alarm systems just by the click of mouse’

I did not know that I do not know

Luckily every day is school day

Thanks to all contributors

[AnthonyB]

A grade C system bears little resemblance to an addressable system, but does have some aspects of a conventional twinwire system, but it is not the same.

It uses 9V combined detector/sounders (normally powered by stepped down mains & back up internal battery or capacitor) and if required combined call points/sounders. The control panel as far as it is is similar in function to that of a 1 zone conventional panel, but is far smaller.

http://www.sensotec.co.uk/firex/PDFS/Firex%20-%20Microfire.pdf

is a Grade C system and the central control panel is not what you would find in a commercial system. Other makes of Grade C system have an even more rudimentary 'panel' little bigger than a single lightswitch fitting would be - a couple of LEDs and buttons.

Grade C systems are sometimes used in commercial premises who size is less than a single zone (as defined in 5839-1), but thats another can of worms!

[kurnal]

Thanks for that Anthony. That link is very interesting as it appears that the materials to install a part 6 grade C system may come to about half the cost of  a comparative  simple two wire one or two zone part 1 system?

[JonnyG]

This is my first post on this site, I've been very interested in this topic because I work for a "large" servicing company who maintains a large number of schools.

I have always assumed that a 240v mains system in any building was fine because it complied to the legislation at the time it was installed. I was also under the impression that an upgrade to a 240v system would only be required when any building work was undertaken by the school because the current legislation would have to be taken into account.

Am I completely wrong? Or drastically misinformed?

[kurnal]

I have always assumed that a 240v mains system in any building was fine because it complied to the legislation at the time it was installed.

This was effectively the case under the old legislation- the fire precautions Act 1971 - for buildings with fire certificates- hotels, factories, offices and shops. (but not schools) A querk of that legislation meant that having once issued a fire certificate the fire authority could never go back and require improved standards- until the owner made changes to the building when those areas would be brought up to modern standards.

Things changed legally with the advent of fire risk assessment in 1997 under the workplace fire safety regulations and the Management of H&S Regs. These brought a duty on the employer (and now the Responsible person) to use the "principles of prevention" to determine their priorities under a risk assessment- one of the principles being "Adapt to technical progress". Without this- and the Bull**** and Persuasion Act 1871 many hotels would still have manual fire alarms without any fire detection as they were issued with fire certificates way back when.
Schools have always been the poor relation.

In the brigade I worked for we were banned by the politicians from inspecting schools in the 80s and 90s  because they could not afford to implement the recommendations we would inevitably make.

[Chris Houston]

This is my first post on this site, I've been very interested in this topic because I work for a "large" servicing company who maintains a large number of schools.

I have always assumed that a 240v mains system in any building was fine because it complied to the legislation at the time it was installed. I was also under the impression that an upgrade to a 240v system would only be required when any building work was undertaken by the school because the current legislation would have to be taken into account.

Am I completely wrong? Or drastically misinformed?

If we are talking about a fire alarm system that has no battery backup, then these are not acceptable.  The signs and signals regs is pretty clear and applies to all fire alarm systems, not just ones that have been installed since the regs came out.

[Chris Houston]

I have always assumed that a 240v mains system in any building was fine because it complied to the legislation at the time it was installed.

This was effectively the case under the old legislation- the fire precautions Act 1971 - for buildings with fire certificates- hotels, factories, offices and shops. (but not schools) A querk of that legislation meant that having once issued a fire certificate the fire authority could never go back and require improved standards- until the owner made changes to the building when those areas would be brought up to modern standards.

But Kurnal,the enforcement of the signs and signals regs was not and is not the duty or the fire service, but instead the HSE, who should expect all places of work to comply with this legislation.

[AnthonyB]

Exactly - as an example in 1997 a certified building that had changed little since the installation of a 240V only system in the 60's could retain it as far as the fire certificate was concerned as the fire authority were powerless to require a change, but in reality would have to plan it's replacement as it breached health & safety law (signs regs) which gives no statutory bar and requires compliance in all circumstances from the day it came into force (although it gave a 2 year change over period for fire signs as these were largely text only whereas most health & safety signs had used pictograms since the late 70's)

[Benzerari]

A grade C system bears little resemblance to an addressable system, but does have some aspects of a conventional twinwire system, but it is not the same.

It uses 9V combined detector/sounders (normally powered by stepped down mains & back up internal battery or capacitor) and if required combined call points/sounders. The control panel as far as it is is similar in function to that of a 1 zone conventional panel, but is far smaller.

http://www.sensotec.co.uk/firex/PDFS/Firex%20-%20Microfire.pdf

is a Grade C system and the central control panel is not what you would find in a commercial system. Other makes of Grade C system have an even more rudimentary 'panel' little bigger than a single lightswitch fitting would be - a couple of LEDs and buttons.

Grade C systems are sometimes used in commercial premises who size is less than a single zone (as defined in 5839-1), but thats another can of worms!

Thank you AnthonyB for the link, after a good break, I have finally had chance to look at the link, certainly (Grade C) has many resemblances to conventional TwinWire system but not totally the same. it is the first time to hear about.

[kurnal]

Sorry to be pedantic but ( I have got to say that I suppose- I love it really)

If we are talking about a fire alarm system that has no battery backup, then these are not acceptable.  The signs and signals regs is pretty clear and applies to all fire alarm systems, not just ones that have been installed since the regs came out.

Just to be absolutely clear the guidance says this:

"33 A guaranteed supply of power or back-up in the event of failure may be necessary for safety signs and signals which require some form of power to enable them to operate (unless the hazard is itself eliminated by the power failure)."

Clearly you would be very brave to continue to use a system that did not have the backup supply but the only reference is in the guidance to the regs, not the regulations themselves. Its not an absolute duty to provide a backup supply but if you dont and something goes wrong you will have to make a very good case to convince the Judge why you did not follow the guidance.

But Kurnal,the enforcement of the signs and signals regs was not and is not the duty or the fire service, but instead the HSE, who should expect all places of work to comply with this legislation

No Chris the Regulations make the fire authority responsible for enforcement in respect of fire safety signs in most premises.

Enforcement
Notwithstanding regulation 3 of the Health and Safety (Enforcing Authority) Regulations 1989(a), the enforcing authority in relation to fire safety signs provided in pursuance of regulation 4(4) as applied by regulation 4(3) (signs provided to comply with the provisions of any enactment) shall be-
(a) the Health and Safety Executive, in the case of-
(i) premises where the Fire Certificates (Special Premises) Regulations
1976(') apply; or
(ii) premises and activities to which these Regulations apply by virtue of
paragraph (2) (b) of regulation 3;
(b) in any other case, the authority or class of authorities responsible for
enforcing the relevant provision of the enactment which applies to the
case.

[Chris Houston]

(Suddenly much less sure of myself on this one but.........)

I would say a fire alarm is not a "fire safety sign" but a "signal"..........

[kurnal]

see " interpretations" on the attached link

http://www.opsi.gov.uk/SI/si1996/Uksi_19960341_en_1.htm