fire alarms help needed!

[martincawte]

hi all

1st off let me say i've only been a member for a couple of months, but this is a great forum, and has already proved invaluable!

anyway

i've taken over the wiring on a block of 20 refurbished flats, and need some advice with the rules on fire alarms.

correct me if i'm wrong but my understanding was that there should be an individual smoke/heat alarm system in each flat, (standard domestic type system with interconnected detectors) AND a communal system run in firesure cable with a proper panel, which should also cover the individual flats as well. ie sounder and detector in each flat.

can anyone tell me if this is correct?

also, does anyone know where you can get a copy of BS 5839 for less than £140!!! (my boss is a cheapskate and im poor!)

many thanks

 

[martincawte]

anyone?

 

[andyb]

Be careful martin, 20 flats is quite a responsibility.
A fire risk assessment should have been carried out and a system designed with this in mind.
My understanding is that if the flats are purpose built and comply fully with the latest building regs then automatic fire detection is not required in common areas. However if a FRA shows up a risk of fire in escape routes then one should be provided.
I think a common system would be for a fire alarm system to bs 5839-1 with automatic protection on stairs and common areas and a heat detector in the entrance lobby of each individual flat. Then domestic smoke detectors to bs 5839-6 in each flat. This will alleviate any false alarm problems disturbing other flats.
There is an excellent guide to bs 5829-1 by a chap called Colin Todd available on Amazon, but I think it is still about £40.00.
As I said, be careful. Why should you take on the responsibility of designing such a system and fire risk assessment.
Good luck

 

[lukese]

you need to first decide to what protection the job is going to be designed, L1, L2, L3, L5 i would imagine being flats it would be L5. as for firesure cable, if your running your loop up and down the same riser it needs to be an inhanced cable, with a minimum burn time of 2 hours, fire sure doesnt live up to this, you will need FP plus, draka plus, or an equivlent, expect your cable price to double. i would not bother protecting the flats due to nuisance alarms and the cause and effect programming will be a nightmare. a sounder in each flat i guess would be sufficient. how many floors are the flats spread over? you could need to prgram phased evacuation ie floor of fire and floor above get evactuated, others are put into alert then evacuated after a certain time. smoke venting interfacing would be a most also i would imagine.

to sum it up mate your not expericanced to take on a job like this and i wouldnt want it on the back of my mind knowing if the flats go up in flames its gonna be my name at the bottom of the commisioning sheets.

get a fire alarm company in to design a "supply and commision" service, they design, you install, they commision. weight of your mind.

 

[martincawte]

thanks guys,

The building is 3 story (ground 1st floor 2nd floor) with one common staircase, no external fire exits either. Walls between the flats are about 12inch cavity stud, with double boarded plasterboard on each side.

personally i wouldnt sign anything to do with the job. its all been installed by some polish guys. I've been taken on to try n get the place sorted out properly, but theres no way id carry the can on this one! The fire alarm system is the main thing im worried about though. i've installed a few before now, theres nothing much to them is there honestly, but ive never designed one and i freely admit i dont know the relevent information to be able to.

that said, theyve boarded the place out, and i just know im gonna be making more holes than a swiss cheese to sort this lot out. the top floor flats have standard smoke detector circuits in each flat, the middle floor has a combined fire system (in red cable) but no sounders and the whole things been cut off somewhere (or several somewheres) and the rest of the communal areas are wired in 3 core and earth flat grey cable. The entire things a mess!

Anyway! if you know of a good company that designs fire systems (the job is in Nuneaton nr Coventry) that would probably be the best way to go for me. i can wash my hands of the entire idea then!