BS 5839 part 6 system (Grade D) In a small office building.

[Tom Sutton]

Is installing a BS 5839 part 6 system (Grade D) in a small office building, two storeys, three offices on the ground floor two on the first acceptable in these days of risk assessment?

[nearlythere]

Is installing a BS 5839 part 6 system (Grade D) in a small office building, two storeys, three offices on the ground floor two on the first acceptable in these days of risk assessment?

No. But strangely enough they can be OK in a small guest house of greater risk.

[kurnal]

It might be ok in some limited circumstances - but how would staff discovering a fire raise the alarm? Would you need a gong as well as the smoke alarms? That would be far from ideal. And a small part 1 system may well be no more expensive than interlinked domestics.

I usually only recommend a part 6 system in a workplace in very limited circumstances, eg to cover inner room situations or where  rooms may be unstaffed and a fire might develop cutting off the means of escape from occupied areas.

[CivvyFSO]

The legislation says a suitable means of giving warning, sufficient detectors and alarms etc.

However, the CLG guidance states:

New automatic fire detection systems should be designed and installed by a competent person. Further guidance is given in BS 5839-1

A better option might be one of the grade C systems knocking around, interconnected detectors and they have also have call points with some rudimentary test/control/silence facilities on them. One of these, accompanied by a similar test regime to a part 1 system, and you are not too far away in my opinion.

There will be people who disagree with this, so you are unlikely to get a solid answer and it will ultimately be down to an assessment of risk by the assessor or RP. It would certainly be worth asking the opinion of the local FRS. They may not want to take the responsibility for saying a part 6 is ok, but what you need to know is whether they would enforce the change up to a part 1 even if the risk assessment took it into account and the RP took the responsibility.

[AnthonyB]

Pt 6 for access rooms, yes, anything else, not ideal.

If it was going to OK such an install it would have to be Grade C, include call points, not be high risk occupancy or fire risk (unprotected cabling) and of course less than the single zone limits in Part 1. I'd want the Part 1 audibility levels as well which would mean loads and loads of smoke alarms if not open plan far above the category probably needed

You might as well put an L5 conventional in really as with just the manual cover plus risk specific detection only (if any) as costs would be similar but with no grey areas.

[Allen Higginson]

Surely (and without knowing the building) that it would be an L4 as a minimum to cover to exit from the first floor to the ground floor and subsequent exit + M?

[kurnal]

As Civvy says " a suitable means of giving warning".

Only the FRA will identify what that is. The benchmark guidance for an occupied workplace is a part 1 M system and we usually build from there depending on the fire risk assessment.

The problem is the segregation of fire alarms into part 6- residential/domestic and part 1 - all other occupancies and nere the twain shall meet.  Cross the demarcation line at your peril.

It might be more helpful if the transition were seamless - if part 1 and part 6 were actually in a performance based single standard covering the provision of alarms from the shout of fire through to the L1/P1 standard, and where the provision is actually based on risk.

As Nearlythere succintly points out is it a bit of a nonsense to get into heated discussions over the sin of installing a part 6 system in a low risk office where everyone is awake and familiar with the building whereas the sleeping guide points people towards part 6 systems in many guest houses in which people, unamiliar with the premises and probably under the influence are fast asleep? (and then misrepresents  BS5839 as it does so)

[Wiz]

I enjoy a heated discussion.

5839 Part 6: Code of practice for the design, installation and maintenance of fire detection and fire alarm systems in dwellings .

[Allen Higginson]

So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??

[nearlythere]

So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??

That appears to be a control measure for an inner room condition Allen. In my time in the FS it was an acceptable way of providing the automatic early warning but that was a time before detection flooding became common, even when it isn't necessary.

[Wiz]

So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??

Yeah, confusing innit!  There are any number of recommendations, advice, opinions and rules of thumb in the fire alarm game. Many of them seemingly contradictory. It also seems that anyone can suggest their own ideas and have it thought as relevant. No wonder it is often difficult to know what to do. No wonder so many people get it 'wrong'!

[Tom Sutton]

If a commercial premises require an electrical fire alarm then cat M is the first consideration followed by the necessary cat if automatic detection is required, all part 1. As for access rooms consider vision panels first or the partition is short of the ceiling, however if detection is the preferred option then connect into the cat M system. Use part 6 for domestic or similar type of premises, like small B+B much less confusion.

[AnthonyB]

So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??

It fits because it is used in the worked example FRA in the DCLG entry level guide based on a two room lock up shop - the 'solution' for the inner room (office/store) is a smoke alarm (not smoke detector) in the access room, manual warning being in the form of a shout of fire and EL a couple of torches.

[Allen Higginson]

So where does the "domestic" mains/battery detector that is installed in manys a petrol station shop between the office and the customer area fit into all this??

It fits because it is used in the worked example FRA in the DCLG entry level guide based on a two room lock up shop - the 'solution' for the inner room (office/store) is a smoke alarm (not smoke detector) in the access room, manual warning being in the form of a shout of fire and EL a couple of torches.

Thanks for clearing that up Anthony - one less thing for the anorak in me to get worked up about!

[kurnal]

Right. How about another spanner in the works.

Fire risk assessment is all about taking reasonably practicable measures to  reduce the level of risk in existing buildings. The smoke alarm achieves this perfectly in the example of the petrol station shop.

But if I was designing a new petrol station shop  with an inner room and submitting the design for Building Regulations approval is it reasonable then to incorporate a domestic type smoke alarm? Or do we think the BCO should reject the design?