Door removal

[lyledunn]

I have a small first floor nightclub occupancy circa 200. Two alternative exits. One is via the main internal stairs to a ground floor lobby which exits directly outside. The exit is also used by the ground floor. The stair is protected with single fire door from the ground floor to the lobby and a single fire door at the entrance to the nightclub on the first floor landing. The building is single storey. As I understand it the first floor door is not required by, for example, ADB  and could be removed whilst still claiming the stair to be protected. Firstly, is that a correct interpretation and secondly am I right in assuming that if the door is removed travel distance is still to the original threshold?

[Phoenix]

I think you mean the night club is single storey, not the building. 

You could remove the door into the club from the stairs but this would not really be in keeping with ADB and you couldn't really claim that travel distance ends at the top step.  But if you are risk assessing the issue then ADB is not a standard you have to use. 

If you do want to allow the door to be removed you should treat the staircase as an accommodation stair (even though it is enclosed at ground floor) which means that no one should have to pass the head of the open staircase to reach the alternative staircase.  Precisely, what "passing the head of the stairs" means is open to your interpretation but the 4.5m rule might be something to consider.  If you don't treat it as an accommodation staircase then you run the risk of being very vulnerable to the risks that could be posed if a fire occurs downstairs and the single door into the ground floor lobby is not fully and effectively closed.

I'm assuming that the alternative exit is large enough to accommodate all occupants.  I know it has to be, but I'm just saying.
I'm also assuming that there is no fire loading within the staircase you want to open up (not that this makes a huge amount of difference if you're treating the stairs as accommodation stairs).

Personally, my default position would be to advise against removal of the door at the head of the staircase because it weakens the overall fire safety measures present, but if the other elements of the risk assessment weigh in favour of a lightening of the installed fire safety provisions then I might accept the door's removal.

[lyledunn]

As always, thanks Phoenix for the expansive and thoughtful reply. I actually meant single compartment rather than single storey.
The two sets of stairs are completely separate. Currently travel distance can be measured to the threshold of the door at the top of the stairs. Removing this door means that it is no longer a protected stair and TD is measured to the final exit at the foot of the stairs which in this case is acceptable. Removal of the door along with a widening of the opening was the suggestion of the owner but the licensing officer flatly refused. I see disadvantage in the door removal but advantage in an unrestricted wider opening.
I recently read a fire report which involved casualties where the chimney effect of door openings led to an accelerated fire growth. My intuition is to side with the licensing officer.