Fire Door plastic plugs in three coloured sections.

[Auntie LIn]

Yes, the three-segmented plugs are an identifier of Leaderflush doors.   It means nothing more than "this door has been manufactured by Leaderflush"

Leaderflush, like all the responsible door manufacturers belong to an independent third party certification scheme.   This requires them to test their doors to current standards (BS EN 1634-1 to be CE-marking ready).   The test house then provides them (at the moment) with parameters within which they can manufacture the tested doorset (otherwise you are stuck selling only what you have tested - size, configuration etc).

I am not aware of a fire door currently on the market that has passed even the BS476:  Part 22 test for 30 minutes without an intumescent seal and the European test is certainly no easier.

With regard to 20 minute doors - there used to be some dead dodgy 'evidence' against the BS476:  Part 8:  1972 test (showing my age here) but certainly from my experience of watching endless tests, you're lucky if, under furnace conditions, you get even 15 minutes without a seal.   Best performances are gained when the leaf/frame gap is almost non-existent - and when did you last see that, consistently on a site?

Doorstops are virtually irrelevant.   Where fire seals are fitted, you don't need a doorstop (see the number of double swing doorsets that have successfully passed the fire test).   Where a doorstop is fitted, size matters chaps!   The bigger it is, the easier it is for the fitter to make a rubbish job of hanging the door, getting paid and cantering off into the sunset before anyone notices.   I favour a small, but perfectly formed 6mm doorstop, just to stop the leaf swinging through the frame for a single action door.   The chippy will have had to make the door fit pretty well  or it will swing straight through - so the gap is going to be probably 3mm or less.   And what are we looking for?  about 3mm!   QED.

[Tom W]

Interesting thanks for the comments. I bow to your superior knowledge but its good to have the debate.

Its seems strips aren't exactly trusted in real life but they are asked for because they are cheap and because the fire service can. Its an easy sleep well at night pill.

It seems strange that from what we have learnt fire doors won't do 30 mins without strips and seals, they will do it in test situations but i would bet a fair bit of money that they don't work properly in real life so again not achieving 30 mins yet we constantly refer to them as 30 min FR doors.

It strikes me as odd that this fib that we all know about is still going and accepted. Its like arguing my pencil has ink. we all know it doesn't but everyone is happy to go along with it and will even make life saving calculations based on that fib

[Fishy]

Interesting thanks for the comments. I bow to your superior knowledge but its good to have the debate.

Its seems strips aren't exactly trusted in real life but they are asked for because they are cheap and because the fire service can. Its an easy sleep well at night pill.

It seems strange that from what we have learnt fire doors won't do 30 mins without strips and seals, they will do it in test situations but i would bet a fair bit of money that they don't work properly in real life so again not achieving 30 mins yet we constantly refer to them as 30 min FR doors.

It strikes me as odd that this fib that we all know about is still going and accepted. Its like arguing my pencil has ink. we all know it doesn't but everyone is happy to go along with it and will even make life saving calculations based on that fib

I really don't get why you infer from the proceeding debate that there is any 'fibbing' going on?  They are needed because a certain item of fire protection won't achieve the performance referenced in national (& international for that matter) codes & guidance without them fitted.  That performance spec represents installations that have been proven over the years to work safely.  No-one (so far as I am aware) has any basis for saying it's wrong, though I stand to be corrected if anyone can reference any published research to that effect.  I've seen 'real' compartment fire tests where they've most certainly activated, but I've also seen tests with ventilation-controlled fires where the fire is sucking air through any gap so greedily that they never get hot enough to activate.  I'd be of the opinion that one would have to be very brave to claim to predict how they'd react on every fire door you ever look at.

The other thing that I'm puzzled about is the "life saving calculations"?  If you're referring to using fire resistance ratings in ASET/RSET calculations, then this is bad practice, because there is no automatic correlation between fire test performance & how long something would last in a 'real' fire.  For example, you can't assume that 30 mins fire separation gives you 30mins in a real fire, because how long the separation lasts in a real fire depends on a multitude of factors, and every situation will be different.  You CAN do time-equivalence calculations based upon fire load for some items of structural fire protection, rather than for fire separation, but that's a completely different matter.

The fire resistance performance spec referenced in codes & guidance is simply a means of ranking performance, nothing more.  Protection against lower risks needs 20 or 30mins F/R; higher risks 60 & protection to fire fighters up to 120.  It does not and never has meant that you're safe from the effects of fire for the stated period if you're behand a barrier of that rating.  Counter-intuitive perhaps, but fact.