FireNet Community
FIRE SAFETY => Fire Alarm Systems => Topic started by: chris_p on April 02, 2012, 04:23:18 PM
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The fire safety team want the fire curtains to operate as part of weekly test (drop down) yet the estates team say this is not wise. The test should be monthly in case the motor burns out! Any advice how to square this circle.
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The fire safety team want the fire curtains to operate as part of weekly test (drop down) yet the estates team say this is not wise. The test should be monthly in case the motor burns out! Any advice how to square this circle.
Is it unwise to do it weekly because the motor might burn out?
Why would it burn out?
Has the Fire Safety Team been advised of any problems with weekly testing?
Has the Fire Safety Team and the Estates Team met to discuss the issues?
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Follow the guidance in the appropriate BS. The equipment should have been designed and installed to a standard capable of meeting this guidance.
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How old is this fire curtain/theatre? The old conditions of licence under the Theatres Act normally specified that the curtain had to be lowererd and raised at each performance so in a full theatre that would be at least once a day six days a week. I have inspected a lot of theatres in the past and I now carry out the annual fire risk assessment for a large city theatre and have never heard such nonsense. My risk assessment recommends the lowering during every performance now that the old licensing conditios have gone as I believe it is a reasonable test.
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Has anyone seen fire curtains being used in a private residential premises?
Links/Info would be appreciated.
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Many thanks for comments
It is a fire curtain in NHS clinic to protect an exit route.
On the phone the manufacturer said weekly operation would be ok but they seem reluctant to put such information in writing!!
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Feel such a fool thougt you were talking about a theatre fire curtain which is really where they belong, did see one provided in a museum to separate an exit route was not impressed. Did find some info and there is a danger that the pressure of the fire can cause them to billow out away from a fire. If smoke stopping is required they must be additionaly designed for that purpose
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Yes there is a trend by architects and some Building Inspectors to use curtains in all manner of unsuitable situations, including to create protected routes from the base of staircases across open plan multi function areas. In one case the proposal - a job I turned down- was to use curtains in this way to create a corridor leading to a firefighting shaft.
In another case the proposal was to enclose an open staircase in a hotel by curtains such that it may be used as a protected route.
I remember quoting for an NHS clinic with small operating rooms somewhere in the North West where a similar arrangement was planned but I said I would only do the job it they redesigned out the curtain so didnt get that one either. And that one required PHE.
It strikes me that the people who design and approve these arrangements have no perception of the effects of fire. Or maybe I am just a dinosaur.
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It strikes me that the people who design and approve these arrangements have no perception of the effects of fire.
It is a case of the designers pushing the boundaries to see how far they get. Then the scribes can write a BS for it later.
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Has anyone seen fire curtains being used in a private residential premises?
It would have to be a pretty big house to require smoke curtains. But then this would be the sort of application that kurnal's talking about in his post above. I too have seen them suggested in spaces that are simply not appropriate for their installation (possibly by the same people - I have to say that some of the suggested applications sound spookily similar). Smoke curtains are appropriate for large spaces such as malls, auditoria (as mentioned above), warehouses and atria.
The smoke models that we use, including CFD, are not sufficiently accurate to be able to give us precise indications of exactly how deep smoke layers might be. In large spaces this inaccuracy can be overcome by allowing decent safety margins in the depths of the curtains. In small spaces we do not have the luxury of ample space to provide generous safety margins and this means that designs have no tolerance for inaccuracies in predictions of smoke behaviour.
The applicability of smoke curtains to large and small spaces is analogous to attempting trend analysis in large and small statistical samples. If we look at the annual figures for fire deaths nationally in the UK then we can see that there are natural fluctuations from year to year but that these are outweighed by the large numbers involved and we can see a true trend going one way or the other (hopefully down!). But if we look at the annual figures for fire deaths within a single county or city of the UK then the natural fluctuations have a much greater significance and can swamp any underlying trend that might exist, making that trend impossible to identify. Attempting trend, or 'regression', analysis on a small sample is more than a waste of time, it is misleading. Similarly, having absolute faith in smoke calculations in small spaces is more than a waste of time, it is dangerous.
This issue of smoke curtains billowing out due to fire pressures is well researched and there is guidance on how to compensate for it. Have a look at BS EN 12101 part 1. This also talks about tests and maintenance and so on but I think it leaves the issue of testing intervals to the manufacturers.
Chris, if the manufacturer has stated on the phone that weekly testing is suitable but won't put it in writing, I would put it in writing for him/her by documenting his/his statement in the log book or fire strategy, and then I would adhere to a weekly testing regime.
Stu
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Fire curtain….. As used in theatres?
Smoke curtain …. As used in atria?
This thread is becoming confusing. ......And...... I believed I knew the difference.
Could someone please clarify? And identify the situations were each is likely to be being used?
;) :-\
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A safety curtain (or fire curtain in America) is a fire safety precaution used in large proscenium theatres. It is usually a heavy fibreglass or iron curtain located immediately behind the proscenium arch. Asbestos-based materials were originally used to manufacture the curtain, before the dangers of asbestos were discovered. The safety curtain is sometimes referred to as an iron in British theatres, regardless of the actual construction material. :o
I don't think its the safety curtain (iron) they are discussing its flexible fire & smoke curtains (Barriers).
FSE (now known as info4fire) produced an article on Active Fire Curtain Barriers. Check out http://www.coopersfire.com/documents/Smoke&FireFSE-Article.pdf
The article explains what Fire Curtains and Fire Barriers are, why they are needed and how they must comply to the new Fire Curtain Specification – BSI PAS 121:2007.
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Has anyone seen fire curtains being used in a private residential premises?
It would have to be a pretty big house to require smoke curtains. But then this would be the sort of application that kurnal's talking about in his post above. I too have seen them suggested in spaces that are simply not appropriate for their installation (possibly by the same people - I have to say that some of the suggested applications sound spookily similar). Smoke curtains are appropriate for large spaces such as malls, auditoria (as mentioned above), warehouses and atria.
The smoke models that we use, including CFD, are not sufficiently accurate to be able to give us precise indications of exactly how deep smoke layers might be. In large spaces this inaccuracy can be overcome by allowing decent safety margins in the depths of the curtains. In small spaces we do not have the luxury of ample space to provide generous safety margins and this means that designs have no tolerance for inaccuracies in predictions of smoke behaviour.
The applicability of smoke curtains to large and small spaces is analogous to attempting trend analysis in large and small statistical samples. If we look at the annual figures for fire deaths nationally in the UK then we can see that there are natural fluctuations from year to year but that these are outweighed by the large numbers involved and we can see a true trend going one way or the other (hopefully down!). But if we look at the annual figures for fire deaths within a single county or city of the UK then the natural fluctuations have a much greater significance and can swamp any underlying trend that might exist, making that trend impossible to identify. Attempting trend, or 'regression', analysis on a small sample is more than a waste of time, it is misleading. Similarly, having absolute faith in smoke calculations in small spaces is more than a waste of time, it is dangerous.
This issue of smoke curtains billowing out due to fire pressures is well researched and there is guidance on how to compensate for it. Have a look at BS EN 12101 part 1. This also talks about tests and maintenance and so on but I think it leaves the issue of testing intervals to the manufacturers.
Chris, if the manufacturer has stated on the phone that weekly testing is suitable but won't put it in writing, I would put it in writing for him/her by documenting his/his statement in the log book or fire strategy, and then I would adhere to a weekly testing regime.
Stu
Thanks Stu, yes it is a whacking great house!
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Thanks Stu, yes it is a whacking great house!
I like to think I have an atrium in my house. Others call it the staircase.
FSE (now known as info4fire) produced an article on Active Fire Curtain Barriers. Check out http://www.coopersfire.com/documents/Smoke&FireFSE-Article.pdf
The article explains what Fire Curtains and Fire Barriers are, why they are needed and how they must comply to the new Fire Curtain Specification – BSI PAS 121:2007.
Tom,
I cannot find reference to BSI PAS 121:2007. Could you give more info on this please.
Stu
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I have no details on the contents but it is available from BSI shop at http://shop.bsigroup.com/en/ProductDetail/?pid=000000000030151490
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I have no details on the contents but it is available from BSI shop at http://shop.bsigroup.com/en/ProductDetail/?pid=000000000030151490
Ok, this is for fire barriers and 12101-1 is for smoke barriers.
Fire barriers do not necessarily require the additional use of natural or mechanical smoke ventilation whereas smoke barriers generally do.
Stu
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I agree it seems European Standard EN 12101 is all about SHEVS and part 1 is about the specification for smoke barriers.
BSI PAS 121:2007 is about active fire curtain barrier assemblies which can have a role to play in both fire engineered designs to assist smoke control and also as an alternative to fire doors and partitions in prescriptive means of escape codes.
I would guess PAS 121 is the appropriate guidance for this post and has a section on maintenance.
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When you read it, just remember who wrote the article and who comissioned the PAS.