Domestic v commercial detectors

[dar1]

Hello all,

Please could you advise whether in low risk commercial premises it is okay to use a a domestic, B&Q type, battery operated smoke alarm by itself or would this need to be connected to the mains, or would this not be acceptable at all.

On a risk assessment basis, with the low risk it is hard to justify XXX pounds when a single £20 alarm (with long battery, tested regularly) is likely to be sufficient but please let me know though if this is incorrect as I realise there are relevant British Standards.

My only thought would be that it should have a back up supply (which the battery would be usually if mains wired)?

Regards,
Darren

[Galeon]

No , you need to refer to BS 5839 Part 1 , you cannot use what you have indicated where the premises is commercial.

[dar1]

Thanks Galleon,

Could you explain the reasoning further for me though please as I was under the impression fire RA legislation is not prescriptive and allowed for controls to be identified on the basis of risk.

So, while I accept what you are saying, is there any particular reason why domestic types can't be used in very low risk situations (this is a small main building with a small office connected to it, with the only need really for detection being that occasionally somebody lone works in the back office and a fire may begin in the main area undetected)?  

Is it lack of sensitivity of the detector, not having a back up, needing to be tested weekly etc?

Also, is the no to domestic in general or domestic hardwired in as well?

Regards,

Darren

[Chris Houston]

They are not suitable.  One is designed for domestic, one is designed for non domestic.  The law permits risk assessment, but you'll have hard job in court arguing that you knew better than the comittee that wrote the relevant British Standard.

The domestic style don't have an alternative power supply and therefore would be a breach of the Signs and Signals Regulations.  It doesn't allow for a risk assessed approach.  All warning sounds and signals must have alternative power supply.

Plenty more reasons, but let's not over complicate a simple situation - they are not suitable.

[Midland Retty]

Hi Dar1

Just to concur with what Chris is saying, if you want a more in depth explanation as to why domestic type detectors are unsuitable then feel free to private message me

[CivvyFSO]

Dar1, for about 30-40 quid you could get a part 6 grade D detector with battery backup and wire it into the mains. According to the BS this is not for commercial premises but the risk assessment may justify this being sufficient. i.e. It could be simply to cover an inner room situation, where 1 detector is all that is required.

[AnthonyB]

A bog standard 9V Domestic Smoke Alarm would not cut it as it has a single power supply, although they have been used in buildings in the past to satisfy L5 type applications & by well meaning people who didn't know any better.

However as CivvyFSO states domestic equipment to grade D or above of BS 5839 may be suitable for certain applications such as inner rooms (they are mains fed with a built in 9V back up cell)

Some of the higher grade domestic systems using interlinked heads, basic control & reset panels or switches and being capable of having manual call points connected are actively marketed as being suitable for smaller commercial uses and have been successfully used in such cases in real situations. Although  I personally prefer sticking to part 1 commercial systems in non domestic premises I have had a very small number of premise where a high grade pt 6 system has been most appropriate weighing everything up.

[dar1]

Thanks all for your advice and further explanation.

The concensus is obviously that just a domestic battery type detector doesn't suffice but there is a view from some that a grade 6 type may be acceptable in certain circumstances.

Civvy, the type of situation you describe is exactly as I was trying to describe i.e. a small, simple building with an inner room, very short escape time/route requiring one detector as an added measure in what is already a very low risk situation.  We have several buildings which have been designed in this way.  

The kind of detector I had been thinking of which appears to satisfy the grade 6 requirements mentioned (and the description says can be used in smaller commercial premises) is the one at the link below:

http://www.sdfirealarms.co.uk/shop/ei161rcionisationsmokedetectorwithlithiumbattery-p-279.html?cPath=29_67_95_100

Thanks again for all your thoughts.
Regards,
Darren

[AnthonyB]

If the premises is too small to need a Category M electrical fire warning system (panel, sounders, break glass units only)but has an inner room situation where the vision panel or 500mm partition gap solutions are not practicable then I would be happy to recommend the product you link to as a solution.

If it has a Cat M alarm, I'd prefer the smoke head to the inner room to be linked to the main fire alarm as a Category L5 install. (I prefer not to rely on someone remembering breaking a glass on the way out after hearing the inner room DS)

[Ricardo]

dar1
It would be interesting to know the building use, size and proposed location/s and purpose for install of the stand alone domestic smoke alarm/s you refer to in your post.

[Galeon]

Is there any issues with sound pressure compliance coming into play if you don't go for a part 1 system ?

[dar1]

The main building is a small library, approximately 8x8m with a 4x4 back office.  I'm confident any fire during normal operation (2 staff) would be detected early by staff/customers but my only concern had been during the occasional period of lone working if a fire developed in the main building.  Though there are obviously a lot of combustible materials, risk assessment would say there are limited sources of ignition, mains are tested every five years, portable equipment subject to PAT, no radiant bar heaters in use, no smoking etc etc.  

However, though there are two escape routes these are both accessed past a computer terminal and till, which is why I had thought a limited alarm system (the hardwired smoke alarm) in this area would be a useful, reasonably practicable additional measure to help further protect their escape route.  To be honest though, if they lone worked with the door open they would probably detect any fire starting themselves!

At the moment they have the standalone detector and the manager tests weekly and changes the battery as needed (this is what I am told anyway!) which is why I asked the original question as to the adequacy of this as I wasn't sure this was acceptable due to the issues you all raised on the back up supply.

I think the alarm would be easily audible even with the door shut due to the short distance but will double check this though I suppose there is a danger people may lone work with their MP3s going still!

Regards,
Darren

[AnthonyB]

Your situation sounds similar to the entry level guide example (although it is a newsagents not a library):



As you can see a single station Pt6 Detector is the solution in this case, so a 240V detector with back up power should suffice - if it isn't loud enough then you could interlink a second one in the rear room to act as a sounder.

[dar1]

Thanks again for sending this Anthony and for your advice.  That does look very similar and so is also reassuring to see.

Regards,

Darren