Smoke / fire curtain

[Mar62]

I have come across a site that has a smoke / fire curtain. Not something I come across much and so my knowledge is limited. It was installed years ago when the area was all open plan. Since then the area has been redesigned with additional meeting rooms, offices etc. I am trying to find out whether the curtain is still a requirement or not. Is anyone able to point me in the right direction please? The issue I have with it is that depending where you were in the area if the curtain came down you wouldn't be able to use the fire exit and would have to travel up a staircase into an open plan office in order to escape.

[col10]

ADB Appendix B.6. If across an escape route it should not be operated by a fire alarm system or smoke detectors.  Should only be released by a heat sensor eg fusible link or heat detector.

[wee brian]

It'll be there as part of a smoke control system, a cavity barrier (fixed in the ceiling void) as an alternative to having a door or wall.

hopefully you can work out which.

[Mar62]

Thanks guys..

[Fishy]

Could be a smoke curtain; could be a fire curtain; could be both!

It would help you to know what the 'cause and effect' regarding it's descent - what activates it?  Does it descend on local/zoned/any detection event?  Is it single-stage descent or two-stage?

Generally speaking smoke curtains will operate in conjunction with a smoke control system (mechanical or natural) - is there one?  Fire resisting curtains are used where you would normally require a wall.   Need to be careful with smoke-operated curtains that they don't descend across a means of escape.  'Fire' curtains are these days usually much thicker than smoke curtains, so that can give you a clue to the performance if it's a more recent installation but this wasn't necessarily the case years ago - the single-layer curtains were used for both.

[John Webb]

If the curtain is for smoke control it probably will not come down to floor level, but remain above head-height, so should not obstruct means of escape. The idea of a smoke control curtain is to channel smoke to where it can be safely discharged or otherwise removed from the building by extract system. It also prevents the smoke from spreading and mixing with fresh air too much, thus maintaining buoyancy and making extraction easier. There should be information available in the building design files - if they've not been lost!

[Mar62]

Thanks for the replies and information. I have no idea on how, when etc as yet. Will be getting the alarm contractor to see how / if its connected first and then get a contractor to have a proper look at it to establish what it is etc.

Many thanks though.