Grade A Fire Alarm power supply

[kernow]

Good Morning

can some of you technical experts answer my question.

i recently veiwed a grade A fire alarm in a new build block of residential flats.

the fire alarm was directly wired into the consumer unit and the unswitched spur was the pop out fuse type.

i was lead to belive that the alarm should be fed directly from the mains via its own consumer unit (red lockable type?) and that the unswithed spur should be a safety isolater type with either a key or secret switch (EL type fish tale)

ive read 5839 chapter 29 and could use other opinions

cheers

[kurnal]

Hi Kernow
Have you access to a copy of BS5839 part 6 2004?
Paragraph 15.4 gives further guidance on power supplies for Grade A systems.

[colin todd]

Ahhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh!

[kurnal]

Someone trod on your toe Colin?

[colin todd]

I knew I should have stuck to vet medicine.  At least animals dont try to read standards.

[Tom Sutton]

kernow which type of system are you talking about a BS 5839 part 6 or BS 5839 part 1. Category A is a part 6 system and what to refer to as chapter 29 is in part 1 you need to be clear which type of system you are referring to.

[kurnal]

Yes Tom, you are correct.

Part 6 does refer back to part 1 to a great extent in respect of power supplies.

The arrangement described by Kernow could be compliant but we also dont know which part of the building is covered by the fire alarm or to whose supply the  fire alarm is connected to- the landlords or one of the flats?
What is covered and why?

[kernow]

The system is Rafiki grade A LD3 covering the communal areas only, with the power fed from the landlords supply DB.

[kurnal]

Kernow
Take another read of the BS and you will see that subject to labelling the installation is probably compliant. Why is the alarm installed? Is it to operate ventilation systems or alert residents? Is it linked to the flats in any way or are they wholly self contained? If it is intended to alert the residents are they likely to hear it?

What instructions will residents be given on hearing the common areas fire alarm?

[Tom Sutton]

Kernow

You should check out BS 5839 part 6:2004 "15.2 Recommendations for power supplies for Grade A systems" which states  "(a) Power supplies for Grade A systems should comply with the recommendations of Clause 25 of BS 5839-1:2002, with the exception of 25.4e) plus two other clauses.

Then go to BS 5839 part 1:2008 and check out Clause 25 except 25.4(e).

[colin todd]

Tam,  BS 5839-6 does not apply to the common parts, so this whole issue is founded on misconceptions.

[Tom Sutton]

I stand corrected Colin I should have read clause 1 (Scope) and as part 1 only applies then Grade A is irrelevant. I hope that's right, anyway I am blaming you Kernow confusing a wrinkley.

[AnthonyB]

Ah, Rafiki, a 'Screwfix special' fire alarm system, the sparkie's friend.

I'd put money on it not being required at all!

[David Rooney]

Tam,  BS 5839-6 does not apply to the common parts, so this whole issue is founded on misconceptions.

So am I right in saying this means that systems advertised as suitable for HMOs - and there are a couple when googled, both hardwired and radio, need to meet part 1 requirements in the common areas when the HMO is more than two storeys or floor area greater than 200m sq ??

[kernow]

Thanks all for your replies, (even the unhelpful one)

maybe i should have been clearer with my question, so here goes.

the system is a Rafiki grade A L2 Automatic fire detection and alarm system.

it consists of call points and smoke detectors/sounders in the communal stairs and landing area/ escape route.

the fire alarm is wired from the landlords supply consumer unit and the spur is a pop out fuse type, with fire alarm do not switch off on it.

im led to believe that the fire alarm should have its own consumer unit - (that can be locked) and fed directly from the mains, with a safety isolator switch between the lockable consumer unit and the fire alarm control panel.
here is an excerpt from Bs5839: p1: 2002

29.2 e) ‘ Means should be provided for double pole isolation of the mains supply to all parts of the system; the isolation facilities should be suitably sited , in the vicinity of the equipment served, for use by maintenance technicians without the need for access to remote parts of the building. It should be possible to lock the facilities in both the normal and isolate positions to prevent unauthorised use

29.2 g) Every isolator, switch and protective device that is capable of disconnecting the mains supply to the fire alarm system should be situated in a position inaccessible to unauthorized persons or be protected against unauthorized operation by persons without a special tool

the answer im looking for is: is this system compiant with Bs5839 p1:2002 A2: 2008 on not: yes or no. as i believe it is not.

hope this makes it clearer to answer