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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Fire Safety => Topic started by: BCO on October 16, 2008, 11:00:20 PM
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A FRS are debating/considering whether to serve notice on a building owner for lack of AOVs in the common corridors of a single stair high rise block of self contained flats.
The building is owned by the Local Authority and is used as social housing. It is an existing building that was built in the 60s. The corridor is about 8m long and openable vents are provided to the corridors. (Although the OVs have become unusable and require repair). If the building was built today it would require AOVs to the corridor to comply with the minimum requirement. Therefore, it may seem reasonable to insist on the AOVs. Or would it?? I can see the dilemma of the FRS when considering the risk and measuring this building against current guidance, however, if this approach was adopted in all buildings then the alterations required would be vast.
So, should they or shouldn’t they serve notice?
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The building would have been erected to the codes of practice appropriate at the time. The methods of staircase ventilation were very different to current thinking. The whole philosophy has changed but there is no real assurance that the new approach will be any more effective than the previous approach.
In the old days of lateral ventilation the whole thing was designed around the direction of the prevailing wind and an average 4mph breeze. If the wind is in the wrong direction it will not work.
On the other hand the new approach is based on BRE research with assumed fire sizes, fires at a certain distance from the flat door, doors partially left ajar and the stack effect pulling inlet air in from the staircase into the lobby. Fires, the weather and people cannot be guaranteed to act in this way.
My personal view is that it is totally unreasonable to require a change in the design philosophy of the building. It is important to restore the ventilation to its original standard and if cost effective to update OVs to AOVs where reasonably practicable.
I bet there are much more important issues to be addressed though- standards of fire doors to the staircases and fire resisting glazing that would make a far greater contribution to the safety of the building.
And handling of refuse and keeping escape routes clear.
Yes we need to adapt to technical progress- but the proposed enforcement would be tantamount to the Department of Transport serving notices to install safety cabs, ABS and latest emissions controls on all fire appliances within 3 months irrespective of the vehicles age.
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I totally agree, it would not be appropriate to insist on AOV's in a communal area of a block of social flats.
In my experience AOV's are often vandalised beyond recognition in a matter of days. Definately go for a reinstatement of the original ventilation as it likely the old system will be more robust. In addition it requires little maintenance which is often an issue in social housing.
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I am not sue where this retrospective bit is coming from. The buildings were built and passed on the regulations of the day and whilst we progress forwrd fairly quickly especially over the last 50 years, it seems nonsense to try to redesign buildings in such an ad hoc way. People still drive and look after vintage and veteran cars and perhaps that is the issue, one of maintenance, not of redesign. Should we look at past failures in shopping centres and have them completly redesigned as well to the new thinking on fire sizes.
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I have been involved recently with some 14 storey flats, some single staircase some two staircases. On the day I visited a glazing company were just finishing replacing all of the windows with double glazed units including the staircases. Unfortunately they had replaced all the openaable windows in the staircases with fixed shut windows, thefore removing the possibility of smoke ventilation. My risk assessment recommended the replacement of openable windows in the staircase to at least the same as the old 1960 standard.
FRS were consulted by the Housing Organisation and the FRS were happy with a single openable window at the highest level.
One point to note, replacing windows is a Building Regulations requirement, unless useing a FENSA company. When I spoke to the FENSA company they had no idea of the need for smoke ventilation in the staircases of flats.
As Kurnal states although smoke ventilation is important some of the other issues in High Rise flats are more of a concern.
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FRS were consulted by the Housing Organisation and the FRS were happy with a single openable window at the highest level.
Yes I have come across this too and whilst it seems fine for lower rise blocks of say 4 storeys I feel uneasy about it in the old high rise single staircase blocks. Some of these had louvres as POVs of at least 1 sq m at each level- the stair was almost outside. Many of those built in the early sixties are pretty high up to 20 storeys and have no proper firefighters access other than the single stair, protected often only by flimsy glazing from the common lobby. A single vent at the top relies on bouyant smoke and inlet air to work. My gut feeling is that additional ventilation at intermediate levels may give some insurance against cool smoke and unusual weather conditions
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Why not go the whole hog and insist on an enginereed solution to make up for the extra 0.5m above ADB standard? That will teach them to own an old building!
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A notice involves a statetment that the law has been broken annd failure to comply will lead to prosecution. The only definitive answer wil come from a court.
But the key question is "Is it reasonably practicable to retro-fit AOV?" The test for reasonably practicable involves balancing the quantum of risk against the sacrifice in time money and trouble to avert the risk. If the balance is grossly disproportionate then it is not a reasonably practicable precaution.
How much life and limb will be saved by retro-fitting AOV? If the notice only mentions one building then the risk has to be considered specific to that one building. If the notice specifies all the high rises without AOV then the risk can be shown to be collectively greater but the effort goes up considerably. Either way I think such a notice could be succesfully contested as going beyond reasonably practicable.
An HSE tactic to bring laggards up to modern standards was to isssue a notice requiring a plan to identify all offending equipment/operations and create a programme to deal with the problem. It was used some years ago to get the steel industry to spend a lot of money on noise reduction. Doing it all now might not be reasonably practicable but having a plan to progressively achieve improvements over a defined time scale starting with the worst cases and involving a planned committment of resources would be reasonably practicable.
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One point to note, replacing windows is a Building Regulations requirement, unless useing a FENSA company. When I spoke to the FENSA company they had no idea of the need for smoke ventilation in the staircases of flats.
Did you know, companies can "Self-Certify" under the FENSA scheme. Only available to UPVC supplier though.
Timber boys have to go the Building Regs route.
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It seems that this is the hot topic at the moment, i have been hearing a lot about them lately from colleagues and consultants.
I don't believe in this circumstance it would be necessary to install AOV's. as has already been said, you can't start bringing all properties up to ADB standards.
I would expect however, that the current systems (ov's) are brought back up to their original condition.
If the building was designed with those measures, the least the enforcing officer should expect are that those measures are maintained, unless of course the RP can show within his risk assessment an alternative solution to overcome the problem.