Student Accom/kitchen doors being held open

[Big_Fella]

A new build, of 220 student bedrooms across 3 floors.

Fire Alarm system has been designed to L1 with Optical/Heat sensors in bedrooms and corridors and heat sensors within kitchens (2 kitchens per floor).  All bedrooms and kitchens open directly onto the escape corridors.

Building control have asked a question as to weather the kitchen doors should be held open via a magnet releasing on alarm as they believe the doors may be 'wedged open'.

The arguement against this would be if there is a smoldering fire in the kitchen and the door is held open by a magnet the heat sensor wouldnt go off until a considerable amount of heat is generated and then you're relying on the sensor within the corridor to pick up the smoke (which could be 5-6 metres from the kitchen door) causing smoke to impair the escape corridor.

Is this a good enough arguement against having a hold open magnet and advise the building control that the building is managed in such a way that 'wedging' open the door is virtually non-existant?  As we all know this does happen in student accomodation.  

Or accept the doors should be held open by a magnet and released on fire activation and risk a large amount of smoke passing into the escape corridor?

[Wiz]

A new build, of 220 student bedrooms across 3 floors.

Fire Alarm system has been designed to L1 with Optical/Heat sensors in bedrooms and corridors and heat sensors within kitchens (2 kitchens per floor).  All bedrooms and kitchens open directly onto the escape corridors.

Building control have asked a question as to weather the kitchen doors should be held open via a magnet releasing on alarm as they believe the doors may be 'wedged open'.

The arguement against this would be if there is a smoldering fire in the kitchen and the door is held open by a magnet the heat sensor wouldnt go off until a considerable amount of heat is generated and then you're relying on the sensor within the corridor to pick up the smoke (which could be 5-6 metres from the kitchen door) causing smoke to impair the escape corridor.

Is this a good enough arguement against having a hold open magnet and advise the building control that the building is managed in such a way that 'wedging' open the door is virtually non-existant?  As we all know this does happen in student accomodation.  

Or accept the doors should be held open by a magnet and released on fire activation and risk a large amount of smoke passing into the escape corridor?

This type of problem has been discussed many times before on Firenet - Use the search facility to reference.

My favourite resolution is to leave the exsisting heat and smoke as they are, but add an additional smoke in the kitchen (not connected/configured to initiate an alarm condition) that only releases the kitchen door holds if it senses any smoke in the kitchen.

[kurnal]

Are these proper kitchens where cooking takes place? or just brewing stations?

I think Dr Wiz's solution may result in the door closing itself so often it may still be wedged. But it may be worth a try. Optical detector would be better than ion.

Presumably the new build will not include dead end corridors? If it does those doors must remain shut and a Madame with a big stick will be the only solution.

Other factors to be considered are the ventilation from the kitchen, sensitivity and temperature of operation of a heat detector, possible addiional subdivision of corridor if two way travel is possible. alarms that sound if the kitchen door is left open. There is a unit designed for this situation called the dorwatcher

http://www.hoyles.com/acatalog/dorwatcher-kitchen-door-alarm.html

[Big_Fella]

There is a central stairwell for escape but the corridors are dead ends.  The kitchens are proper kitchens with cooker/microwave kettle fridge/freezer etc in them

[kurnal]

Sorry about this Big fella but other questions that should be considered are

How long are the dead ends?
How many bedrooms served in each dead end corridor?
Is it a single stair serving all 220 bedrooms?
Is the kitchen  at a remote end of the dead end or is it closer to the stair than the bedroom?
Is there a fire door between each corridor and the staircase?
Is there any security staff present  in the block?


The setup sounds a little familiar - its not a new block at a redbrick uni in the West Mids is it?

[Big_Fella]

Sorry about this Big fella but other questions that should be considered are

How long are the dead ends?
How many bedrooms served in each dead end corridor?
Is it a single stair serving all 220 bedrooms?
Is the kitchen  at a remote end of the dead end or is it closer to the stair than the bedroom?
Is there a fire door between each corridor and the staircase?
Is there any security staff present  in the block?


The setup sounds a little familiar - its not a new block at a redbrick uni in the West Mids is it?

From stairwell to the dead end is approx 22 metres
each corridor has around 7 bedrooms
there are multiple staircases, but you cannot go from one staircase across a corridor to another.  One staircase serves a particular part of the building/floors and bedrooms
the kitchen in 'most' scenarios is closest to the stairwell.  Therefore to go into other bedrooms you would have to pass the kitchen.
There is a fire door between the stairwell and the corridor
The site will be manned for approx 12 hours a day (generally day time)


It's not in the West Mids

[kurnal]

Its a tragedy that in full knowledge of the nature of fire risk and students that someone has designed a building to this layout and even more so that it has been subject to the supervision of a building control officer. How on earth has this design got past scrutiny against  the ADB which recommends a maximum 9m travel distance in a dead end corridor in sleeping accommodation?
Sorry Big fella that outburst does not help you much though does it.

I think I would identify the weaknesses and ask the architect and BCO to come up with a solution at their expense.
The dead end is much too long. The kitchen is in the wrong place. That kitchen door is absolutely key to fire safety in this sleeping accommodation, both for the protection of the dead end corridor and for the protection of the staircase serving the top floor. Students being students will wedge it open. If the place is now built and occupied then the only solution may be as suggested by Dr Wiz above- together with a water mist system covering the kitchen.