Protected escape route

[hammer1]

Morning chaps,

Got a little query in regards to escape routes. We have an existing building (70s built) which has a small area on the 1st floor which houses x 2 toilets and a small kitchen area for staff. There is a single staircase which leads down onto the ground floor. There is FD30S separation from the kitchen area to this staircase.

The issue is once you go through the FD30S door on the ground floor/bottom staircase you arrive in a open plan area which is the stock room. You have an exit to your left which passes through the stock and a exit right which leads out into the rear of the shop and to a exit.

There is a L2 type fire alarm system, staff members are trained in fire evac and fire awareness, you would have a max of 4 people on the 1st floor at anyone time, the stock room is nearly 90% occupied by staff during open hours.

I have been advised to install a compartmentation between the left, separating the stock room, so in event of fire in stock room, it will not spread to the staircase area. I have also been advised to install compartmentation to the right separating shop to the stock entrance, however a fire shutter is in place to do this currently.

Travel distance from 1st floor to exit on right is about 18 m and the fire exit through the stock room is about 25 m

The compartmentation suggested is magnetic doors due to this route having high volume of use (deliveries etc)

Surely having a robust early warning fire system, trained staff good management controlling risk of fire developing is a viable alternative to this costly measure as persons on the 1st floor take about 4-5 seconds to egress down the stairs (from fire drills), stock room being occupied to raise early warning of fire.  Plenty of extinguishers around.

Can understand this in new builds or alterations but seems a bit OTT.

Thought I pass this by you guys to see you thoughts were.

Cheers

[CivvyFSO]

Look at the small premises guidance in ADB, and imagine the place with no doors protecting the stair at all, it would probably not be too far off complying would it?

[hammer1]

Cheers Civvy,

I agree, I have also used the section 5.58 in regards store rooms in shops do not need separation if fitted with AFD or sprinklers.

However where are they coming from in regards to installing a fire separation between the stock room on the right and the staircase??? 

[CivvyFSO]

It is hard to say not knowing the exact layout, but they are probably trying to create a protected escape route from the first floor where one isn't really needed. You need to nail down some guidance that it complies with in its current form, or at least something close and work from there.

[nearlythere]

It is hard to say not knowing the exact layout, but they are probably trying to create a protected escape route from the first floor where one isn't really needed. You need to nail down some guidance that it complies with in its current form, or at least something close and work from there.

I think they are trying to create two seperate escape routes from the stairway enclosure.
I don't actually think this layout could be considered to fall within the Small Premises criteria as per ADB.

[Phoenix]

No, I don't think the small premises section will apply (because it doesn't sound like the three metre rule at the bottom of the staircase is being complied with) but its underlying principle might be relevant.

This should really be viewed as an inner room.  The fact that the inner room is up a flight of stairs simply adds some travel distance (and hence time) to the escape route.  There are travel distance limitations applicable here, in the order of 18m for single direction and 45m for more than one direction (or maybe 12m and 25m (depends...)).  With two exits from the access room (the stock room) you might find that this appears to be a satisfactory layout when viewed in these terms.  However, irrespective of what the numbers appear to indicate this boils down to a simple question that can only really be answered on site: If a fire occurred in the stock room when no one was present can it be guaranteed that the fire will be detected early enough and that people on the first floor will respond rapidly enough to ensure that they can escape through the stockroom before the fire gets large enough to make it difficult?

Bear in mind the nature of the stored items.  If it is clothing then some pretty rapid fire development can be expected and the layout is less likely to be acceptable.  If it's jewellery stored in metal cabinets then it is more likely to be acceptable.

Stu