Travel Distance Query

[Tadees]

I have been thinking for some time about an issue.

I recall, when being taught at Moreton that, travel distance stops in a protected staircase, different fire compartment or final exit?

In a house converted in to a HMO or hostel, however, where two or three rooms will inevitably open on to the staircase and tenants will have to pass these rooms on the way out, can we still count this as a protected staircase or is it now a protected corridor where travel distance can't be stopped?

In other words can travel distance be stopped outside the bedroom door or can it only be stopped once the final exit has been reached?

[nearlythere]

I have been thinking for some time about an issue.

I recall, when being taught at Moreton that, travel distance stops in a protected staircase, different fire compartment or final exit?

In a house converted in to a HMO or hostel, however, where two or three rooms will inevitably open on to the staircase and tenants will have to pass these rooms on the way out, can we still count this as a protected staircase or is it now a protected corridor where travel distance can't be stopped?

In other words can travel distance be stopped outside the bedroom door or can it only be stopped once the final exit has been reached?

How many storeys are in your situation Tadee?

Corridors have a limitation on travel distance depending on how many stairways serve them and the building use. It is the vertical travel distance in a stairway which is generally unlimited so long as it is suitably protected and has a final exit directly from it.

[kurnal]

The old fire precautions act guides used to define a protected route, and used words to the effect that if the only doors to a staircase were from wcs with no fire risk and doors to corridors the staircase could be considered a protected route. It went on to say that if doors from rooms opened directly into a staircase then judgement would have to be exercised as to whether the staircase could be considered a protected route.
See we used to risk assess even in the days of certification!

[Phoenix]

Yes, there must be a whole generation of fire safety practitioners who, largely, don't recall the distinction we used to make between an enclosed route and a protected route.  Kurnal, I don't think there are any current guides left that continue to support the need for that extra line of fire protection before we call an enclosed route a protected route (correct me if I'm wrong).  Standards have dropped.

Tadees, in general the travel distance will stop at the door to the protected staircase.  Remember that there are two stages of escape from HMOs, hostels, etc.  The first stage is getting to the door that leads from the flat/bedsit/room to the protected staircase (possibly including a corridor) and this is where travel distance is considered.  The second stage is down the protected staircase to the exit.  The staircase should be protected to the appropriate level, according to the applicable LACORS, CLG, ADB, etc guidance, so there is no need to consider travel distance within it.

Yes, people may have to pass the doors to the rooms where the fire is but that is why the current guidance recommends the various levels of protection.

Stu

[kurnal]

Kurnal, I don't think there are any current guides left that continue to support the need for that extra line of fire protection before we call an enclosed route a protected route (correct me if I'm wrong).  Standards have dropped.

Yes, people may have to pass the doors to the rooms where the fire is but that is why the current guidance recommends the various levels of protection.

Thats a good point Phoenix and of course we did not have categories of fire alarm and detection  L1- L5 in the early days of the old FP Act and its guidance. Whether standards have dropped or whether additional detection is a reasonable trade off  for passive measures is another debate.  I believe it is and remember with horror many of the buildings that were ruined by the provision of silly little lobbies in each room to achieve double door proptection.

[nearlythere]

Kurnal, I don't think there are any current guides left that continue to support the need for that extra line of fire protection before we call an enclosed route a protected route (correct me if I'm wrong).  Standards have dropped.

Yes, people may have to pass the doors to the rooms where the fire is but that is why the current guidance recommends the various levels of protection.

Thats a good point Phoenix and of course we did not have categories of fire alarm and detection  L1- L5 in the early days of the old FP Act and its guidance. Whether standards have dropped or whether additional detection is a reasonable trade off  for passive measures is another debate.  I believe it is and remember with horror many of the buildings that were ruined by the provision of silly little lobbies in each room to achieve double door proptection.

And of course detection was not really an appropriate alternative to DDP but it did provide a better means of protecting people as they they could be warned much earlier of a fire in the building rather that having to find out by the smell of smoke or by an overheating floor.

[Tom Sutton]

Tadees at Moreton we were all instructed on non residential premises therefore I would suggest that guidance still applies. For converted houses its a different matter and I think the Lacors guide should be used however depending on size you may have to use the sleeping risk guide. In lacors they accept rooms or flat doors, opening on to a protected staircase with AFD and there is no set travel distances just a general discussion. As the risk increases i.e. height of building in storeys the bung in a higher grade fire alarm simples!

[Midland Retty]

It depends Thomas.

The "DDP" approach was designed to keep smoke from entering the staircase. Some buildings over a certain height still require lobbied or corridor approach to allow for the time it may take for persons evacuating from upper floors

There used to be many a fire officer and consultant who would say that a category L1 fire alarm system complete with one line of fire resistance onto a staircase was an acceptable compensatory feature for the lack of DDP (except for tall buildings which would need lobby or corridor approach regardless of the category of fire alarm system proposed)

Tadees your psot reflect the thoughts of many who have undertaken a course at the College of Knowledge about where and when you can stop travel distance.

There are many single staircased buildings out there which only have one line of f/r protecting the staircase. Trying to go around and double door / lobby every corridor or room would be impossible, and frankly cuckoo.

I would suggest however that it would be safe to say that one line of FR + AFD in the escape routes and rooms directly of escape routes would constitute a protected route (in buildings under the required height for lobby / corridor protection).  I await the shower of ridicule for saying that :-)

[nearlythere]

I generally agree MR. DDP was in some cases stupid as in small but multi storey premises,as K said, offices where reduced in size by half to provide a lobby.

I always thought it was a tad puzzling because if you had one room or corridor with a stairway serving either end why would single door protection be adequate as a fire could effect both.

[Midland Retty]

Ifyou had fire doors protecting each staircase then in reality (unless its a tall building which does require lobbies) fire shouldn't be able to develop so quickly to take put both staircases before people could escape. And even if some pimply herbert propped open one of those fire doors you should still be able to turn your back and head for the alternative staircase.Of course it does depend on whether upper floors have access to the two staircases

[Tom Sutton]

MF my point was we were instructed at Moreton on non-residential premises and where travel distance finish is relevant. But in small residential premises like those Tadees was referring to, the Lacors guidance does not concern themselves on travel distance other than about 9M to the front door of the flat when you may need to consider the sleeping guide. They never consider DDP they just upgrade the AFD when the risk increases.

[Midland Retty]

Hi Tom I know what you mean, I was coming from the angle that whilst the Lacors guide will look at increasing standards of AFD depending on the size and type of premsies - the level of detector coverage however is usually constant (Category LD2 - LD3 in shared houses) the increase being the grade of system (normally from Grade D to a Grade A).

The detector coverage is the more salient point in this discussion as an LD2 Grade A won't protect a staircase any more than a Grade LD2 D system would for example.

[Tom Sutton]

Agreed 

[AnthonyB]

I would guess that the double door instead of AFD exists primarily because when the guidance was being first formulated a long time ago smoke detection in fire alarm systems was in it's infancy, heat detection predetermined and most systems were manual for life safety, the property protection aspect of buildings being met with the use of sprinklers. Therefore greater physical protection was the most viable solution due to limits of technology.

Technology has moved on though and as such it is not unreasonable to use AFD as compensation - the only danger being tilting the swing too far the other way and removing too much physical protection.

[Tom Sutton]

the level of detector coverage however is usually constant (Category LD2 - LD3 in shared houses) the increase being the grade of system (normally from Grade D to a Grade A).

The detector coverage is the more salient point in this discussion as an LD2 Grade A won't protect a staircase any more than a Grade LD2 D system would for example.

Based on the above what would be the advantages of upgrading from an interlinked grade D to a grade A?