Green break glasses

[SidM]

I've read virtually every thread on this forum regarding the subject topic and it might just be me but instead of shedding clear light and advice on the issue I am even more confused than before.  Is anybody prepared to put their neck on the line and explain in plain English (these being the operative words) when and where green break glasses are required and how they work without delving into unexplained electrician terminology.  Some of us don't understand double-pole, PIR sensors, push rocker switches etc as we are not electricans, never have been or never will be.

Predominantly there are two type of doors that I come across, those on magnetic locks and automatically sliding doors.  If a punter that is a bit dim like me asks you, do I need a green break glass on this door and if so why, would somebody on this forum be able to explain the differenct scenarios without reverting to convoluted technical terminology.

[Tom Sutton]

Check out https://www.ucl.ac.uk/efd/maintenance/fire/documents/UCLFire_TN_001.pdf it should start the discussion and remember its the LFB.

[nearlythere]

I've read virtually every thread on this forum regarding the subject topic and it might just be me but instead of shedding clear light and advice on the issue I am even more confused than before.  Is anybody prepared to put their neck on the line and explain in plain English (these being the operative words) when and where green break glasses are required and how they work without delving into unexplained electrician terminology.  Some of us don't understand double-pole, PIR sensors, push rocker switches etc as we are not electricans, never have been or never will be.

Predominantly there are two type of doors that I come across, those on magnetic locks and automatically sliding doors.  If a punter that is a bit dim like me asks you, do I need a green break glass on this door and if so why, would somebody on this forum be able to explain the differenct scenarios without reverting to convoluted technical terminology.

Maybe I could suggest that these types of doors should failsafe in the event of a mains or subcircuit power failure or on operation of the fire alarm and provided with a manual override facility suitably located in the immediate vacinity with the method of operation clearly indicated.
Does that not cover all?

Try BS 7273-4:2007 Code of practice for the operation of fire protection measures – Actuation of release mechanisms for doors

[SidM]

Check out https://www.ucl.ac.uk/efd/maintenance/fire/documents/UCLFire_TN_001.pdf it should start the discussion and remember its the LFB.

Link does not work.  Would you be able to email please.

[SidM]

I've read virtually every thread on this forum regarding the subject topic and it might just be me but instead of shedding clear light and advice on the issue I am even more confused than before.  Is anybody prepared to put their neck on the line and explain in plain English (these being the operative words) when and where green break glasses are required and how they work without delving into unexplained electrician terminology.  Some of us don't understand double-pole, PIR sensors, push rocker switches etc as we are not electricans, never have been or never will be.

Predominantly there are two type of doors that I come across, those on magnetic locks and automatically sliding doors.  If a punter that is a bit dim like me asks you, do I need a green break glass on this door and if so why, would somebody on this forum be able to explain the differenct scenarios without reverting to convoluted technical terminology.

Maybe I could suggest that these types of doors should failsafe in the event of a mains or subcircuit power failure or on operation of the fire alarm and provided with a manual override facility suitably located in the immediate vacinity with the method of operation clearly indicated.
Does that not cover all?

Try BS 7273-4:2007 Code of practice for the operation of fire protection measures – Actuation of release mechanisms for doors

That makes sense although from my reading ALL MORNING the requirement for a green break glass is only where the punter cannot guarantee that the door will failsafe in the event of a fire or does not have appropriate battery back up

[Midland Retty]

I've read virtually every thread on this forum regarding the subject topic and it might just be me but instead of shedding clear light and advice on the issue I am even more confused than before.  Is anybody prepared to put their neck on the line and explain in plain English (these being the operative words) when and where green break glasses are required and how they work without delving into unexplained electrician terminology.  Some of us don't understand double-pole, PIR sensors, push rocker switches etc as we are not electricans, never have been or never will be.

Predominantly there are two type of doors that I come across, those on magnetic locks and automatically sliding doors.  If a punter that is a bit dim like me asks you, do I need a green break glass on this door and if so why, would somebody on this forum be able to explain the differenct scenarios without reverting to convoluted technical terminology.

Hi Sid

Green break glass boxes should be used wherever you have doors held closed by electro magnetic locking devices.

Normally any doors held closed by electro magnetic devices release to the open / unlocked position when the fire alarm activates.

The magnetic liocking devices are connected to the fire alarm by cable and something called a relay. All the relay does is tell the magnets to release when the fire alarm sounds.

Sometimes the relay can fail, meaning that whilst the fire alarm activates the doors wont release.

The green box is used as a fail safe means of opening the door if the doors fail to open. The green box is connnected directly to the electromagnetic locking device.

I have seen some electricians wire the green box into the the curcuit from the fire alarm (the same circuit which is wired to the relay l talked about earlier. This is incorrect, green boxes must be wired directly to locking device on the door and nothing else)

When you hit a green box it interupts the power supply to magnetic locking device making them release immediately, thus unlocking the door.

Green boxes should not be used in areas used by the public (ie pubs clubs supermarkets) as often the public don't know what the green boxes are for or what they do.

Instead green boxes should be used in staff areas or areas where staff will assist / marshall the evacuation of the public.

Green boxes can be disguised. Take a young offenders institute with electronic locking doors which are held shut to prevent the offenders escaping.

Some young offender might get to know that by pressing green boxes will release the doors and they can escape.

So to prevent the toe rags from doing a midnight flit the green boxes can be disguised as light switches, they can be configured to be only activated by key, infact can be made to look like a million different things!

At the end of the day the green box is just a switch, a bit like a light switch - you press it and something happens. The grren box is just a switch to release the door locking mechanism.

Hope this helps

[SidM]

I've read virtually every thread on this forum regarding the subject topic and it might just be me but instead of shedding clear light and advice on the issue I am even more confused than before.  Is anybody prepared to put their neck on the line and explain in plain English (these being the operative words) when and where green break glasses are required and how they work without delving into unexplained electrician terminology.  Some of us don't understand double-pole, PIR sensors, push rocker switches etc as we are not electricans, never have been or never will be.

Predominantly there are two type of doors that I come across, those on magnetic locks and automatically sliding doors.  If a punter that is a bit dim like me asks you, do I need a green break glass on this door and if so why, would somebody on this forum be able to explain the differenct scenarios without reverting to convoluted technical terminology.

Hi Sid

Green break glass boxes should be used wherever you have doors held closed by electro magnetic locking devices.

Normally any doors held closed by electro magnetic devices release to the open / unlocked position when the fire alarm activates.

The magnetic liocking devices are connected to the fire alarm by cable and something called a relay. All the relay does is tell the magnets to release when the fire alarm sounds.

Sometimes the relay can fail, meaning that whilst the fire alarm activates the doors wont release.

The green box is used as a fail safe means of opening the door if the doors fail to open. The green box is connnected directly to the electromagnetic locking device.

I have seen some electricians wire the green box into the the curcuit from the fire alarm (the same circuit which is wired to the relay l talked about earlier. This is incorrect, green boxes must be wired directly to locking device on the door and nothing else)

When you hit a green box it interupts the power supply to magnetic locking device making them release immediately, thus unlocking the door.

Green boxes should not be used in areas used by the public (ie pubs clubs supermarkets) as often the public don't know what the green boxes are for or what they do.

Instead green boxes should be used in staff areas or areas where staff will assist / marshall the evacuation of the public.

Green boxes can be disguised. Take a young offenders institute with electronic locking doors which are held shut to prevent the offenders escaping.

Some young offender might get to know that by pressing green boxes will release the doors and they can escape.

So to prevent the toe rags from doing a midnight flit the green boxes can be disguised as light switches, they can be configured to be only activated by key, infact can be made to look like a million different things!

At the end of the day the green box is just a switch, a bit like a light switch - you press it and something happens. The grren box is just a switch to release the door locking mechanism.

Hope this helps

Excellent.  Thank you.

[FIRE]

In a residential block of flats that uses an electro magnetic door entry system (will fail safe in power failure). System is not linked into a fire alarm system. Door has a push to exit button to release the door. Do you think a green box should be installed to protect against earth frame faults or a faulty switch?

[nearlythere]

b

In a residential block of flats that uses an electro magnetic door entry system (will fail safe in power failure). System is not linked into a fire alarm system. Door has a push to exit button to release the door. Do you think a green box should be installed to protect against earth frame faults or a faulty switch?

Link to FA is belt and braces.
If door lock functions as required, if there is a power failure or not, this could be assessed as OK.
However, what else could effect the proper functioning of the lock? What is the failsafe? Is the means of providing the failsafe facility remote from the door? Can the the failsafe fail along with the normal mode. Can the link between the door lock and the failsafe control fail?

[jokar]

Retty, 10 out of 10 for the explanation and that is not meant to be patronising.

[Wiz]

In a residential block of flats that uses an electro magnetic door entry system (will fail safe in power failure). System is not linked into a fire alarm system. Door has a push to exit button to release the door. Do you think a green box should be installed to protect against earth frame faults or a faulty switch?

If the door relies solely on a button to exit the button then surely there is potential for failure trapping people in the building. If so, as a first step it should obviously be linked to automatically release on fire alarm. Secondly, a green break glass would be essential according to some advice, although it will probably be abused and the door left unlocked for all to enter.
The liklihood of 'earth frame faults' would require an electrically conductive doorframe but many people would advise the use of a double-pole green break glass unit in all circumstances in the hope that any electrical short likely to by-pass the switch of a single pole green break glass will also cause a 'dead short' of the lock power supply, blow the power supply output fuse and fail-safe release the door.
I understand that there is a new BS that may apply to these sort of doors. I haven't seen it yet but I would guess it will include the recommendation for a double-pole green break glass unit. Anyone else seen this BS yet?
I personally feel that there is a lot of overkill in some advice offered for the emergency releasing of fire doors in as much as the attempt to reduce the risk to zero can be ridiculously expensive and, at the end of the day, it is impossible to make these sort of doors totally fail-safe.

With reference to the document  ( found at the link: https://www.ucl.ac.uk/efd/maintenance/f … TN_001.pdf ) suggested, in an earlier posting, as a point of reference, I would ask FireNet members their opinion on the following:

1) Is everything recommended in the documents supported by a BS or other recognised official recommendation, or does it contain elements over and above these on the basis that the document issuing body feels 'it would be nice to have these things as well'. If they do this, does anyone else agree that it could and does cause much confusion.

2) One of the documents is issued by LFEPA. Apart from premises still requiring a fire certificate, what authority do LFEPA have to demand compliance with their own guidance notes?

3) The LFEPA document clause 2.4 states ' Under no circumstances is an electronic door release to be connected to a local fire alarm sounder circuit. In all cases, the recommendations within Clause 19 of BS 5839 part 1: are to be observed'.
Can anyone see any relevance between the first sentence and the second sentence of the LFEPA document clause 2.4?

[Clevelandfire]

Retty, 10 out of 10 for the explanation and that is not meant to be patronising.

Cracking explanation Retty!.

You say that green boxes can be disguised, Ive never come across this before, but now you mention it I  can see how they could be disguised easily.

Are there any "off the shelf products" to do this or do you need a sparky to wire something bespoke for you?

[kurnal]

Dr Wiz
Surprised to find you so far away from your usual refuge, have you strayed from matrons bosom?

You have brought with you an incomplete link to the UCL website- please go back and collect the missing pieces, stick it all back together with gaffer tape and we may be in business.

Question 1 and 2- Did you see the CFOA / IFE document written by Graham Shiel a number of years ago? As far as I am aware, though very dated, (1999) this remains the most complete overview of this subject. The local Enforcement Authority can ask for whatever they like, as you know its down to the Responsible Person to decide how they will comply with the Fire Safety order and the Enforcement Authority cannot prescribe conditions- if they disagree the courts will decide on appeal.

As for your question 3 the answer is no. There does not appear to be a logical link between the two sentences.

Sentence 1 is essential. Many hospitals used to have electronic locks wired for convenience to the sounders, trouble was when the sounders were silenced to help the staff and fire service get on with their work and searches, all the doors used to lock again which was not a great deal of help to anyone.  

Sentence 2 seems to be an unrelated matter and I think should have been a seperate paragraph.
I take it to mean that in interfacing the locks to the fire alarm then due regard must be paid to the evacuation strategy for the building, recognising the alarm zone boundaries and ensuring that only the locks in the zones being evacuated open on operation of the fire alarm. Similarly where staff alarms are provided then consideration should be given to the desired cause and effects in relation to the locks.

[rb health and safety]

Are these always linked to the fire alarm?  If so do they always show up on the fire alarm panel as a seperate item or just within the Zone.

www.rbhealthandsafety.co.uk

[TickityBoo]

I've read virtually every thread on this forum regarding the subject topic and it might just be me but instead of shedding clear light and advice on the issue I am even more confused than before.  Is anybody prepared to put their neck on the line and explain in plain English (these being the operative words) when and where green break glasses are required and how they work without delving into unexplained electrician terminology.  Some of us don't understand double-pole, PIR sensors, push rocker switches etc as we are not electricans, never have been or never will be.

Predominantly there are two type of doors that I come across, those on magnetic locks and automatically sliding doors.  If a punter that is a bit dim like me asks you, do I need a green break glass on this door and if so why, would somebody on this forum be able to explain the differenct scenarios without reverting to convoluted technical terminology.

Hi Sid

Green break glass boxes should be used wherever you have doors held closed by electro magnetic locking devices.

Normally any doors held closed by electro magnetic devices release to the open / unlocked position when the fire alarm activates.

The magnetic liocking devices are connected to the fire alarm by cable and something called a relay. All the relay does is tell the magnets to release when the fire alarm sounds.

Sometimes the relay can fail, meaning that whilst the fire alarm activates the doors wont release.

The green box is used as a fail safe means of opening the door if the doors fail to open. The green box is connnected directly to the electromagnetic locking device.

I have seen some electricians wire the green box into the the curcuit from the fire alarm (the same circuit which is wired to the relay l talked about earlier. This is incorrect, green boxes must be wired directly to locking device on the door and nothing else)

When you hit a green box it interupts the power supply to magnetic locking device making them release immediately, thus unlocking the door.

Green boxes should not be used in areas used by the public (ie pubs clubs supermarkets) as often the public don't know what the green boxes are for or what they do.

Instead green boxes should be used in staff areas or areas where staff will assist / marshall the evacuation of the public.

Green boxes can be disguised. Take a young offenders institute with electronic locking doors which are held shut to prevent the offenders escaping.

Some young offender might get to know that by pressing green boxes will release the doors and they can escape.

So to prevent the toe rags from doing a midnight flit the green boxes can be disguised as light switches, they can be configured to be only activated by key, infact can be made to look like a million different things!

At the end of the day the green box is just a switch, a bit like a light switch - you press it and something happens. The grren box is just a switch to release the door locking mechanism.

Hope this helps

Good summary although I'd disagree that they shouldn't be used in public places.  Many public places with powered automatic sliding doors have green boxes e.g. shops / shopping malls / cinemas etc.  BS7273-4 and the Scottish Fire Safety Guides cover the provision of these manual release controls and do not exclude places to which the public have access.  The green break glass unit should be labelled "break to open door" or something similar and I'm sure signage is available to further explain there use, if deemed necessary.