Proposed cafe at the base of an atrium

[Rocha]

Please could you guys give me any ideas or concerns with a proposed cafe seating area at the base of an atrium in a 9 storey office building.

No cooking is to take place here (apart from the heating of sandwiches) and mainly consists of a small cafe bar, 4 sofas, 6 smaller chairs and tables on a carpeted area.  This area does not impinge on the MoE and as far as I can see the fire load (as mentioned above) introduced is approximately (maybe slightly more) than the the 14 metre perimeter sprinkler controlled fire specified in the fire strategy document for the smoke control system of the atrium.

The base of the atrium is protected by side wall sprinklers, thus redusing the risk further.
All furniture and cafe bar have been tested to the equivalent BS or european equivalent for fire rating.

Is there anything I am missing???

Thanks,

R

[Pip]

I am sure one of the technical people will give you a better resoponse,and most of it sounds ok,however,although the fire load may be the same or less than a 'controlled sprinkler fire,if the 'perimeter' is bigger than the 14m square design fire size,then in theory it could entrain more air thus more smoke therefore overcome the extraction etc.As I say,just a thought and I am sure one of the experts will clear that one up.

[CivvyFSO]

Does the strategy actually allow fire loading in the base? Is the 14m perimeter in reference to a fire in the office areas, and the sprinklers/smoke control controlling the products of that fire as it comes into the atrium?

Something possibly to bear in mind (if you haven't already) is that regardless of the furniture meeting flammability tests it is still fire loading, so even though it is low risk for ignition it still needs to be taken into account to find out if the system can handle it. As Pip says, something such as this could tip the balance and make the difference between a smoke layer that is removed effectively and a smoke layer that descends.

[slubberdegullion]

Just looking through old posts.  This may all be sorted out now but I have to mention a couple of things.

It is hard to see how the sidewall sprinklers will have any effect upon the fire size.  How will they ever go off?  (Unless, of course, the fire is against the wall beneath them!)

There is pretty straightforward guidance on what is allowed and what is not allowed in BS5588 part 7 (Atrium buildings) - please look at this - follow the flow chart.  It has no fire engineering in it but it will help you assess whether or not you need to incorporate any fire engineering features into the building and it will also let you know what levels of construction are required

Stu.

[nearlythere]

Is the atrium the only means of escape from each occupancy?
Is atrium enclosed to fr standard?