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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Fire Safety => Topic started by: nearlythere on October 07, 2014, 09:18:11 PM

Title: Stairway enclosures without detection
Post by: nearlythere on October 07, 2014, 09:18:11 PM
What do we think of this folks.

10 storey building with two stairway enclosures. On has final exit and the other (main stairway) exit via a lift lobby and reception.
Single point of access to each stairway at each level.

No service shafts in either stairway.

Main Stairway - Completely sterile and no detection within stairway but detection in adjacent room which is lift lobby at all levels.
Alternative Stairway - Also sterile with no detection in enclosure but has protected lobby approach on each level from open plan office area containing detection.

So I'm thinking - what's the problem?
Title: Re: Stairway enclosures without detection
Post by: Davo on October 07, 2014, 09:57:01 PM
Nearlythere

Liklihood of remaining sterile? How is the security? Arson?

davo
Title: Re: Stairway enclosures without detection
Post by: nearlythere on October 08, 2014, 07:34:16 AM
Nearlythere

Liklihood of remaining sterile? How is the security? Arson?

davo

Very likely to remain sterile & arson? How do you deal with a single stairway condition?

Security staff at main entrance. Rear escape stairway secure from outside access.

Title: Re: Stairway enclosures without detection
Post by: Mr. P on October 08, 2014, 10:24:41 AM
Suitable/reasonable control/management, 2 way escape. Are stairs sized for number of occupants?
Title: Re: Stairway enclosures without detection
Post by: nearlythere on October 08, 2014, 09:13:06 PM

So I'm thinking - what's the problem?


Dunno.  What is it?
That what I'm asking? Lots of opinions would make good chat. Is that not one of the points of the forum? Debate?
Title: Re: Stairway enclosures without detection
Post by: kurnal on October 08, 2014, 10:28:35 PM
What is the building used for NT? Single or multi occ?
Title: Re: Stairway enclosures without detection
Post by: nearlythere on October 09, 2014, 06:44:57 AM
What is the building used for NT? Single or multi occ?
Single.
Title: Re: Stairway enclosures without detection
Post by: kurnal on October 09, 2014, 05:34:19 PM
What's it used for NT? Offices? Hotel? Flats? Hospital? Firework factory?
Title: Re: Stairway enclosures without detection
Post by: Clevelandfire 3 on October 09, 2014, 05:49:01 PM
No problem to me. Theres 2 staircases. We always say you will only have one fire. people can turn their back and go the other way. Doesn't matter if both staircases become poorly managed so long as theyre both separated. 
Title: Re: Stairway enclosures without detection
Post by: nearlythere on October 09, 2014, 09:24:41 PM
What's it used for NT? Offices? Hotel? Flats? Hospital? Firework factory?
Office.
Title: Re: Stairway enclosures without detection
Post by: kurnal on October 10, 2014, 07:06:33 AM
Presumably at least one of the staircases is a firefighting shaft with a firefighting lobby due to the height of the building........ I  suggest that if building it today you would follow bs5839 and incorporate detection in accordance with the Relevant  L category, but if encountering it on an FRA as an existing building it might be difficult to justify the cost / benefit of a retro fit of detection especially where the staircase(s) are firefighting stairs with firefighting lobbies in a single occupier (or well managed multi occ ) building.
Title: Re: Stairway enclosures without detection
Post by: colin todd on October 13, 2014, 11:56:24 PM
Why would you need afd in an office building.
Title: Re: Stairway enclosures without detection
Post by: Davo on October 14, 2014, 07:30:54 PM
How long have you got...........

davo
Title: Re: Stairway enclosures without detection
Post by: colin todd on October 15, 2014, 10:17:52 PM
I have infinite patience. It comes from dealing with the English FRS.
Title: Re: Stairway enclosures without detection
Post by: Wiz on October 16, 2014, 10:00:05 AM
Why would you need afd in an office building.

just to quote a few from Table A.1 of BS5839-1 which could apply to office buildings:

a) Buildings in which other fire precautions, such as means of escape, depart from recognized guidance.

b) Buildings with "inner rooms", from which escape is possible only passing through another ("access") room, where there is inadequate vision between the inner room and the access room.

c) Buildings in which automatic fire detection is required to operate other fire protection systems (e.g. magnetic door holders)

d) Situations in which fire could readily spread from an unoccupied area and prejudice means of escape from occupied areas.

e) Any building in which automatic detection is provided as a requirement of a property insurers or to attract an insurance premium discount.

I'm sure there must be other reasons which could apply.

I haven't got a clue who was involved in creating BS5839-1, but I imagine they would know what they are doing. They are my heroes and I look up to them!  ;)
Title: Re: Stairway enclosures without detection
Post by: nearlythere on October 16, 2014, 10:42:25 AM
Why would you need afd in an office building.

just to quote a few from Table A.1 of BS5839-1 which could apply to office buildings:

a) Buildings in which other fire precautions, such as means of escape, depart from recognized guidance.

b) Buildings with "inner rooms", from which escape is possible only passing through another ("access") room, where there is inadequate vision between the inner room and the access room.

c) Buildings in which automatic fire detection is required to operate other fire protection systems (e.g. magnetic door holders)

d) Situations in which fire could readily spread from an unoccupied area and prejudice means of escape from occupied areas.

e) Any building in which automatic detection is provided as a requirement of a property insurers or to attract an insurance premium discount.

I'm sure there must be other reasons which could apply.

I haven't got a clue who was involved in creating BS5839-1, but I imagine they would know what they are doing. They are my heroes and I look up to them!  ;)

I think those would be control measures coming under a Cat L5 system.
Title: Re: Stairway enclosures without detection
Post by: Wiz on October 16, 2014, 12:32:09 PM
Why would you need afd in an office building.

just to quote a few from Table A.1 of BS5839-1 which could apply to office buildings:

a) Buildings in which other fire precautions, such as means of escape, depart from recognized guidance.

b) Buildings with "inner rooms", from which escape is possible only passing through another ("access") room, where there is inadequate vision between the inner room and the access room.

c) Buildings in which automatic fire detection is required to operate other fire protection systems (e.g. magnetic door holders)

d) Situations in which fire could readily spread from an unoccupied area and prejudice means of escape from occupied areas.

e) Any building in which automatic detection is provided as a requirement of a property insurers or to attract an insurance premium discount.

I'm sure there must be other reasons which could apply.

I haven't got a clue who was involved in creating BS5839-1, but I imagine they would know what they are doing. They are my heroes and I look up to them!  ;)

I think those would be control measures coming under a Cat L5 system.

That might be true of some of them, but even L5 has automatic fire detection. More applicably the last one might relate to a P1/P2 category system.

Anyway, the answer answers the specific question correctly.

And I'd have thought Mr C.T. would know all this.  ;)
Title: Re: Stairway enclosures without detection
Post by: kurnal on October 16, 2014, 05:03:59 PM
Why would you need afd in an office building.

i know a bloke who sat on BSI working group responsible for BS5839-1 and I am sure he would be happy to talk to you about it Col, just be warned he does grind on a bit.
Title: Re: Stairway enclosures without detection
Post by: colin todd on October 18, 2014, 10:30:49 PM
Wiz it is right you should , but nothing Almost Here said suggests that any of these apply.  You don't get inner rooms off stairways by definition.
Title: Re: Stairway enclosures without detection
Post by: Wiz on October 20, 2014, 09:42:53 AM
Wiz it is right you should , but nothing Almost Here said suggests that any of these apply.  You don't get inner rooms off stairways by definition.

Fair point. I was being flippant answering the actual specific question without regard to the original post.