Author Topic: Double action final escape mechanism  (Read 5915 times)

Offline Hightower

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Double action final escape mechanism
« on: December 16, 2009, 09:20:06 AM »
Thoughts please

A break glass release mechanism is fitted to a final emergency exit door.  To make an escape occupants would need to break the glass, which then allows a bolt to be manually released and the door then pushed open.  The reason this type of mechanism has been provided is that small children use the premise and from a duty of care perspective the manager doesn't want them, under normal circumstances, escaping to fresh air without adult supervision.  It is reasonable to consider that children will be allowed anywhere in the building at anytime so there restriction to the escape area would be difficult (and not desirable.)

I have calculated that the building's total occupancy could be to a maximum of 160 persons and as such I would want a 'push bar' mechanism for immediate release.  Has anyone got any ideas for an appropriate solution to this problem, or can the present break glass mechanism stay in place?

Appreciate your thoughts

Hitower
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Online AnthonyB

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Re: Double action final escape mechanism
« Reply #1 on: December 16, 2009, 11:17:07 AM »
The numbers would normally warrant an anti-panic fastening as you say. However I am guessing that the premises are not a place of public assembly but a childcare type premises - as such I would expect a high level of staff discipline and management such that evacuation would be in an orderly fashion.

With this in mind a mass panic rush against the doors is far less likely and staff could use the mechanism (sounds like an Ashworth or Redlam panic bolt) quickly and effectively.

I would ensure that all staff are conversant with the mechanism & thus not be put off by the padlock on it, that a hammer & chain is affixed & that a Ceramtube is used instead of the cheap glass alternative (you don't want a child stepping on broken glass)

An electronically operated lock with local break glass override and fire alarm interface would be a better middle ground.
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Offline afterburner

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Re: Double action final escape mechanism
« Reply #2 on: December 16, 2009, 11:27:58 AM »
A magnetic lock interfaced with the fire alarm system is used in some primary schools.

Stops the door being used from either side unless the fire alarm activates or a discreet high level staff access button is used internally.

will need an emergency 'green box' release mechanism too to deactivate the magnetic lock for any non - fire emergencies.

Could you not consider a panic latch type lock sited at a level beyond young children's reach?

Or an 'out of frame' alarm when the door is opened (could be remote to an office or local and sound off at the door as it's opened?

Offline Dinnertime Dave

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Re: Double action final escape mechanism
« Reply #3 on: December 16, 2009, 12:33:00 PM »
A magnetic lock interfaced with the fire alarm system is used in some primary schools.


Not always keen on this in schools/childcare environment as these locks can be fitted on internal lobby doors with the fire alarm call point adjacent to the final exit (ie the wrong side of the secured door). i have dealt with childcare facilities that have children placed in care or on the child protection register, this arrangement could put staff and children at risk.
 
A green break glass and good staff training is better - imo.

I would not be over worried in the example posted by Hightower     

Offline Hightower

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Re: Double action final escape mechanism
« Reply #4 on: December 16, 2009, 12:43:43 PM »
Guys

Thanks for your thoughts

The place is actually a gym, used as a school of gymnastics, also they take in special needs and small children for special activities.  Some facilities are off the main gym area and roaming kids could find a final exit if they were inquisitive.
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Offline Wiz

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Re: Double action final escape mechanism
« Reply #5 on: December 16, 2009, 02:34:02 PM »
Some push bars locks are made with integral switches. This switch could be used to operate a warning alarm that the door has been opened. The warning alarm could in even be the fire alarm system!
With the above you would still have the simple mechanical opening benefits of a push bar but also with a warning that it had been pushed. So it wouldn't prevent someone using it, but the staff would know it had been.

Offline Hightower

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Re: Double action final escape mechanism
« Reply #6 on: December 16, 2009, 04:42:02 PM »
If a 'keep shut' mechanism was to be fitted with interface to the AFD would permissions need to be sought from the FRS?
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Offline nearlythere

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Re: Double action final escape mechanism
« Reply #7 on: December 16, 2009, 06:49:00 PM »
If a 'keep shut' mechanism was to be fitted with interface to the AFD would permissions need to be sought from the FRS?
It is not a case of asking permission but more of establishing the position of the FRS in relation to how it views this matter.
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Online AnthonyB

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Re: Double action final escape mechanism
« Reply #8 on: December 16, 2009, 08:03:49 PM »
A magnetic lock interfaced with the fire alarm system is used in some primary schools.


Not always keen on this in schools/childcare environment as these locks can be fitted on internal lobby doors with the fire alarm call point adjacent to the final exit (ie the wrong side of the secured door). i have dealt with childcare facilities that have children placed in care or on the child protection register, this arrangement could put staff and children at risk.
 
A green break glass and good staff training is better - imo.

I would not be over worried in the example posted by Hightower     

good point - an example of where the risk to security is higher from risk of fire and thus justify only having the local override.
Anthony Buck
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Offline afterburner

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Re: Double action final escape mechanism
« Reply #9 on: December 17, 2009, 08:42:52 AM »
Following the Dunblane tragedy restrictions to entry in many primary schools was achieved by magnetic locks preventing all the exit doors being opened from the outside, with staff accessible manual overides in place for routine comings and goings. Timed 'off times' accounted for morning breaks and lunchtimes with the fire warning system being the ultimate override.

The knock on effect of this provision was to restrict pupil movement out of the building and this was perceived as an unintended bonus. Thus external security provided internal security by default. When closed, these doors are protected metal roller shutter doors to prevent access.

The F&RS were informed of the provisions and the operational processes and procedures and the schools all adopted the same outcomes.

Security controls on fire exits is a very common need and we, the advisors on the topic, need to recognise everyone's concerns and provide a practical solution. We need rapid and easy egress through the exit doors, when we need to evacuate from a fire. Until we need to evacuate from a fire those doors can be controlled to prevent use. It's these preventative control measures which (rightly) trouble us.