Suspended ceiling

[Fishy]

Can you help me with interpretation of Table A3 in ADB3?  If I am reading it right it seems to indicate that providing SOF characteristics are met, the existing suspended ceiling in my case, if deemed to be W, X, Y or Z can contribute to 60min fire protection?

Sorry - wishful thinking, I'm afraid.  Table A3 presupposes that the suspended ceiling has evidence of fire resistance performance that demonstrates it can contribute to the fire resistance of a floor (e.g. BS 476: Part 21), and places limitations on the situations where it can be applied (e.g. if the void above the ceiling were full of combustible stuff then it would be likely that its contribution might be compromised).  It doesn't indicate that a ceiling that meets the conditions in the table will contribute to the fire resistance of a floor, to any defined level.

[kurnal]

Whilst I fully agree that where building works are carried out National Guidance should be followed the issue of proportionality must also be considered in my opinion. In this case it seems that a loft ladder is to be replaced by a staircase. If it is the case that the loft is still to be used for storage only, (we have not been told) then I cannot see why, in addition, the fire resistance of the floor needs to be improved. Lyle - please let us know.

In the scheme of things premises don't come much lower risk than a single storey doctors surgery.

One thing that has always bugged me is that with small low risk premises "applying the book " is often onerous and in my experience these premises are often dealt with a heavy hand by many enforcers when compared to much larger, higher risk premises or developments.  That is where a comparative analysis can be useful.

[lyledunn]

There will be no one on the first floor other than to retrieve a file. Even then, travel distances are mostly met. It is only from the most remote end of the floor where travel distance becomes an issue at around 30m. We have made the BC application. I will let you know how it goes. Regardless of what BC say, from a moral perspective, I need to be confident that I am not compromising fire safety unnecessarily.

[wee brian]

Its a little harder to make your escape/effect a rescue if the flames are coming through the floor or the floor has collapsed.

As somebody has suggested, you might be able to use the approach taken for storage platforms in AD B. but this will restrict the way the space is used etc etc.

[nearlythere]

There will be no one on the first floor other than to retrieve a file. Even then, travel distances are mostly met. It is only from the most remote end of the floor where travel distance becomes an issue at around 30m. We have made the BC application. I will let you know how it goes. Regardless of what BC say, from a moral perspective, I need to be confident that I am not compromising fire safety unnecessarily.

At least you will have someonrpe to make the decision Lyle. It will depend on who looks at the submission.

[lyledunn]

Well the builder went ahead with works on the strength of a site meeting with the BC officer and his boss. Project was quick to finish. All happy. Then comes the response from NIFire and Rescue which rejects the proposal simply on the grounds of TD (nearly 30 instead of 18). They are happy to review their decision but on chatting with officer he feels 30 has an intolerable feel to it, whatever that means.
Everyone on the new floor will move immediately on activation of the L2 FA so no pre movement time to consider. It took me and the practice manager 37seconds to reach the car park in front of the building at a quick but not hurried pace.

[nearlythere]

Well the builder went ahead with works on the strength of a site meeting with the BC officer and his boss. Project was quick to finish. All happy. Then comes the response from NIFire and Rescue which rejects the proposal simply on the grounds of TD (nearly 30 instead of 18). They are happy to review their decision but on chatting with officer he feels 30 has an intolerable feel to it, whatever that means.
Everyone on the new floor will move immediately on activation of the L2 FA so no pre movement time to consider. It took me and the practice manager 37seconds to reach the car park in front of the building at a quick but not hurried pace.

The response being on paper following the BC submission? It would be normal for it to reject something which the book considers excessive. Your next move would be to request a site meeting with FR Service to discuss and to demonstrate that despite the TD you are still able to evacuate that area well within 2.5 minutes. The whole point of TD limitations is to ensure the recommended evacuation time but then this is benchmark stuff. The L2 will give immediate warning of fire to enable the evacuation to commence immediately. That is as good a measure than no alarm system with 18m TD.