Fire alarm system, type, should I, etc.....

[NDG Elecs]

Hi All,

I have just been sent a spec for a small extension to a nursery school to quote for. I have worked off spec sheets before but have never been involved in installing a zoned fire alarm system. Which is included in the spec. The spec does not mention any thing specific so am I right in thinking that the local building inspector and fire officer would be wise to consult for requirements.

The new stand-alone timber building itself will be quite small (5x8 metres), and consists of a store, disabled and non disabled toilets, kitchen, and classroom. So five rooms in total. Obviously the spec is the spec, but things can obviously change if agreed and warranted.

So I have two main questions:

Firstly, does an extension as described warrant a zoned system. There are not numerous corridors and multiple classrooms etc. The location of a fire within such a small area would be pretty much obvious and I would be happy to discuss this with the relevant people. Would a grade D system with manual call points not suffice. Obviously an auto dialler to fire brigade would be required.

Secondly, despite having insurance cover, I have never installed such a system so would it be a better idea to sub-out this aspect of the work out to a firm that understands BS5839 a lot better than I do. If I got the work I would be more than happy to do so, though I am also keen to learn more. Also, there is a possibility that the fire alarm system may require an alarm link to the adjacent main building.

Any thoughts welcomed.

Quite a big part of me is saying leave well alone!

Thanks, Neil

 

[Yorkshire]

Ctec small panel in building maybe a 2 zone alarmsense detectots with sounder bases as for link look in exisiting panel for class change "cc" terminal put a 4 core betweem panels as if no class change there is another way to do through relays but requires spare zone in either panel

 

[tazz]

Don`t use class change function or 4 core cable, as this is against the reqs........
A zone consists of 2,000m sq or aprox 20 detectors. But as a minimum on a system, must consist of 2 zones & 2 sounder circuits. If the original building has a spare zone use it. If not a small 2 zone conventional panel such as kentec or Haes will be best. Link cable must be 2 x 2 core FP, and taken to a spare zone, at both panels....this allows for monitoring of the cable & panel. Each panel will then show a zone from the other. Panels are programmed for non latched for these zones. allowing auto reset from activated panel....hope this helps

 

[Gazthesparky]

Don`t use class change function or 4 core cable, as this is against the reqs........
A zone consists of 2,000m sq or aprox 20 detectors. But as a minimum on a system, must consist of 2 zones & 2 sounder circuits. If the original building has a spare zone use it. If not a small 2 zone conventional panel such as kentec or Haes will be best. Link cable must be 2 x 2 core FP, and taken to a spare zone, at both panels....this allows for monitoring of the cable & panel. Each panel will then show a zone from the other. Panels are programmed for non latched for these zones. allowing auto reset from activated panel....hope this helps

Hi Tazz

Just a quick question with regards the first couple of sentences. I'm not questioning you but have the regulations changed in the last few years ?

I use to work installing alarms in schools and use to program class change this was over 5 years ago so just wondering if regulations have changed

Also I've adapted systems that have been installed using 4 core cable with the sounder circuit and detector circuit in the same cable

Have the regs changed regarding this

Cheers

 

[tazz]

Been in regs since 1985....Class change is what is states, used to indicate change of classrooms in schools, and not for linking panel together. Reason behind this, cables and panels would not be monitored for fault (o\c s/c) Therefore can not be used as a monitored circuit. Activation must show a zone area for identification. Class change does not show any indication.......FP400 (4 core) must not be used, for combining zones or sounders or both. reason cable damage would result in loss of 2 circuits. Each circuit must be on its own cable.

 

[NDG Elecs]

To me all the responses above may as well be in Hebrew! Have not got a clue what half of it means at all! Not that I am ungrateful! So, given my lack of knowledge, I think I will pass on this aspect of work if I got the job.

OK, as I am at the quoting stage, any rough ball park figures for the fitting of it all, or failing that how many days labour. Guessing at 2-3 days given its a new build and walls etc will be down..I already got a price for a panel etc.. Ta.

 

[tazz]

Don`t be disheartened, its not rocket science......first thing to do is find out what panel and detection is in the original building (make models etc) and any spare zones......The specification will indicate what level of detection is needed, possibly with issued drawings. The sounder and zone circuits are just radial circuits with an end of line resistor or unit, which is for monitoring the circuit. There is always free help on the forum, just ask.

 

[Gazthesparky]

Been in regs since 1985....Class change is what is states, used to indicate change of classrooms in schools, and not for linking panel together. Reason behind this, cables and panels would not be monitored for fault (o\c s/c) Therefore can not be used as a monitored circuit. Activation must show a zone area for identification. Class change does not show any indication.......FP400 (4 core) must not be used, for combining zones or sounders or both. reason cable damage would result in loss of 2 circuits. Each circuit must be on its own cable.

Hi Tazz

Just re read your original post and i read it wrong. I thought that you were saying that class change is not allowed any more but i now realize you were referring to using the class change facility to link a new panel into. As you say this doesnt conform as there is bno way to monitor this. I must learn to read posts properly lol

cheers