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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Community Fire Safety => Topic started by: PGtips on May 11, 2016, 03:50:52 PM

Title: Old lifts in residential block
Post by: PGtips on May 11, 2016, 03:50:52 PM
Hi all - I was wondering if anyone could point me to guidance re lifts in older purpose built residential blocks?
I have a block built in the 1960s - it has a lift installed at that time which runs from the basement with the usual hazards, electrics, residents storage etc to each compartment floor and opens (conveniently for residents) right outside their flat doors. Access to the single stair is via another 2 fire doors. Building is 8 floors in total including basement, one flat per floor. Lift motor room happily at the top.  Existing FRA for the building says install a fire alarm in the common parts, but I'm not sure this makes since, building is occupied by generally older residents as well so I don't fancy them trying their luck if an alarm goes off.  Someone else has suggested an alarm just for the basement area, with auto detection but only a local sounder (for persons in the basement, but linked through direct to Redcare or similar so as the basement is generally unoccupied, F&RS could attend if there were an issue without disturbing residents? Has anyone heard of this type of set up before?  All views welcome!
Title: Re: Old lifts in residential block
Post by: kurnal on May 31, 2016, 09:39:07 AM
A common situation, always a difficult one to call, I guess the biggest risk is a fire in the basement sending smoke up the shaft in a stay put building. Fire prevention in the basement is the order of the day , but my opinion is that a decent minimum 1 hour enclosure at the base of the shaft (to include  smoke stopping properties which the existing lift doors will not provide) and the alarm system you describe is probably the ultimate solution, though some might say OTT. What is the standard of the existing doors to the shaft? Is there any fire separation between the basement accommodation and the base of the lift?
Title: Re: Old lifts in residential block
Post by: Phoenix on May 31, 2016, 03:43:34 PM
I know it won't happen but they should ask for a refund from whoever did their previous FRA. Sounds like it completely missed the point.

What kurnal said.  They have to have fire separation between the risk area in the basement and the basement lift doors.  Should be at least one hour.
Title: Re: Old lifts in residential block
Post by: kurnal on May 31, 2016, 07:29:37 PM
Agreed Phoenix but I have come across many situations like this in which the only fire separation is the lift shaft door, which only provides fire resistance from the landing side (compliant) and no smoke protection to the shaft. There is often a large basement area used for storage, car parking, plant rooms with louvre doors etc.  I have often speculated whether in the event of a fire in the basement the smoke would penetrate into the flat lobbies and if so at what level?
Title: Re: Old lifts in residential block
Post by: Phoenix on June 01, 2016, 01:12:36 AM
I know they exist, and the fact that deaths and injuries have not historically been atttributed to this situation might tend to indicate that the perceived problems may be extremely unlikely to be realised.  The amount of smoke coming out from a closed lift landing door is bound to be restricted in quantity.  So maybe those more avant garde, and cheaper, alarm solutions suggested by others might be appropriate.

However, if smoke gets into the shaft then it will most likely spill out from the top level downwards.  Shafts do have vents in them for pressure equalisation but these could be inadequate for smoke removal, depending on the rate of smoke ingress.  Also, there is possible movement of the lift car that might affect smoke travel in the shaft and there is the possibility of people coming down to the basement via the lift when it is on fire.  On balance I would still recommend the fire separation at basement level.

A similar problem in some flats is the rubbish chute.  I have been to a few fires myself, a little while ago now, where upper floors have been smoke logged due to a fire in the bins at ground floor level.  I think this problem has mostly gone away now due to the normal protection measures given to these chutes.
Title: Re: Old lifts in residential block
Post by: Jim Scott on June 01, 2016, 11:45:10 AM
Clearly ADB feels it's a problem.

5.43 states that any lift that serves a basement storey should be approached via a protected lobby (unless within a protected stair).  It also states that if a lift serves both high fire risk areas and sleeping corridors they should also be protected by lobbies.

A particular client of mine utilises fire curtains to the lift doors within the risk areas, as we have known a few fires to significantly contaminate adjacent areas with smoke through lift shafts.

Of course in the case that PGtips cites, it appears to be a single staircase.  Again ADB does not like this by virtue of 5.44, as the lift should not extend to a basement in these cases.

I would therefore try to adopt a more belt and braces approach, providing a lobby or other protection to the basement lift shaft entrance if possible.  I assume that these are stay put? In which case, I would do everything to tray and avoid any fire alarm provision.
Title: Re: Old lifts in residential block
Post by: kurnal on June 01, 2016, 05:22:34 PM
I agree Jim with what you say and that ADB is clear in its  recommendations. But in dealing with existing conditions encountered during a fire risk assessment the ADB can be of use in evaluating the risk but finding a solution that is reasonably practicable in the circumstances of the case is another matter. The use of curtains may well be of benefit if they prevent smoke spread into the shaft for an appropriate period and maintain integrity for a similar period. 

As for the alarm, I see some merit in PGtips suggestion for a local smoke detector in the basement with a redcare connection. This would not sound a general alarm elsewhere in the building but would ensure that if a fire occurred in the basement somebody would be alerted and may take action to alert an investigate team or  call the fire service. The stay put policy would not be affected and no sounders would be installed in the communal areas or flats. One hour separation  (or more depending on building height) should be enough to hold the fire back for sufficient time for it to be discovered and reported, but basements being what they are in terms of ventilation it could be that the fire burns for long enough to breach the inherent fire resistance of the structure. Of course alternatively it might burn itself out or self extinguish  depending on the oxygen available. To me that's the judgement call for the fire risk assessment. Clever people who are good at hard sums would be able to ascertain the liklihood of each scenario but I am afraid to say I slept very well through those lectures ar Moreton.   
Title: Re: Old lifts in residential block
Post by: Jim Scott on June 01, 2016, 05:52:15 PM
The point I was trying to make Kurnal (probably quite poorly ::)), is that lift shafts are clearly recognised as an issue and the probability of significant smoke spread is high.  Particularly where the entry to the point of the shaft is not appropriately protected.

Acknowledging the process and intent of a fire risk assessment, I believe that where possible, a belt and braces approach should be desirable.  If we were to interpret the true meaning of Article 10, would it not suggest that we should remove the hazards before we look at providing protection measures?

It may be possible that a local detector may work in some circumstances, but of course that will depend on where you live in the country.  For example, if we were to live in Kent, our lovely friends at Kent Fire and Rescue Service would not attend an alert from an ARC unless there was a confirmed fire.  Providing a local alert might work, although that would assume that somebody may actually bother to do something about it.  Fine all the time that you have very diligent residents and/or a concierge.  However, there are too many 'what ifs' that I don't like in that approach.

If we did not have the lift shaft extend to the basement, would we be so worried?  Probably not.  Consequently, I like the idea of replicating that scenario as much as we can.

Clear as mud..... :P
Title: Re: Old lifts in residential block
Post by: PGtips on April 12, 2017, 12:55:47 PM
Chaps - apologies for not thanking you all earlier for your replies! Only just found my amended password for entry to the site! ;D

You will be happy to know the RP did nothing anyway following my report....sigh!