The need for intumescent seals on fire doors

[Auntie LIn]

Midland Retty - you say:  "The doors to each bedroom are fire resisting to 30 minutes standard, are fitted with cold smoke seals and positive self closing device.   There aren't any intumescent strips however."

How are you identifying that they're 30 minute doors?   Is it the nice blue plaque on the door which says 'Fire Door - Keep Closed'?   Or the fact that the leaf feels heavy?   Or that it's a thick door?   None of these are accurate ways of determining the fire resistance of a doorset - you're just guessing.   Could it be that the doors carry some form of plug and/or label?   In which case they MUST have fire seals because they will have been tested with them and you can't claim the performance without.   However...........if you are happy to undertake a risk assessment and provide the property owner with your written opinion that the doors will be fine without fire seals, everyone will be content, won't they?

[Midland Retty]

Auntie Lin

I wont answer the part about  how I identify fire doors, needless to say I dont just check how heavy they are, or if they have a nice blue plaque, have three hinges, go clunk click when they close onto their rebates or any of that nonsense as you suggested.

But you haven't answered my question, what benefit are instumescent strips from a life safety point of view? (other than some buildings Ive mentioned time and time again)

Another question Auntie Lin, and Im not being antagonistic here, but lets say you go into an office block. The doors look like 30 minute fire doors, but have no markings. Because there is nothing to suggest they are 30 minute doors would you ask the RP to change them all for certified fire sets?

[Fishy]

Hi Auntie Lin & Fishy

I understand completely the rationale behind intumescent strips and the way they are tested. I also understand the behaviour of fire doors during fire. I remain largely unconvinced however that intumescent strips offer any real benefit, other than property protection, in most buildings, and thus care needs to be taken by enforcers and assessors alike as to how far they go when pushing for existing fire doors to be upgraded where they are found not to be of the correct standard.

You could argue that the duty to mitigate the effects of fire under the RRO, and the fact that any fire safety plan should not include any reliance on the fire service means that intumescent strips do still have a role to play in some way shape or form.

But this would only be from a building protection viewpoint, not life safety. (save for some premises such as defend in place strategies or large complex buildings where evacuation would be long and protracted)

More and more buildings nowadays have some form of early warning or detection, early detection means quicker evacuation, and hopefully that means the fire service gets called out much quicker too.

And whilst any fire safety plan shouldn't rely upon fire service intervention, early detection does lead in all but a few case to early intervention.

Ive even been to incidents where the fire has been burning for quite sometime before we were called out, and yet still the intumescent hasn't activated. I dont buy the argument that early intervention is a factor in why we dont see many strips activate.

Imagine you are an enforcer or assessor standing in an 60 bed hotel. The doors to each bedroom are fire resisting to 30 minutes standard, are fitted with cold smoke seals and positive self closing device. There aren't any intumescent strips however.

Are you going to issue them a report saying all bedroom doors should be upgraded within 6 months, or would it not be better to suggest that when the fire doors need to be replaced the new fire doors meet current standards?

I hear what you say, & disagree with some aspects of it, as I've stated above - particularly on the view that the strips are considered to have no life safety function.  However, if you believe that you've got sufficient justification to support variation from the relevant good industry practice, then I guess we'll just have to agree to disagree.

The answer to your final question is that it would depend upon the risk, & I would also have the determination that I've referred to above in mind.  As I've stated a number of times above, upgrading is not necessarily expensive, so if I considered that the risk warranted it then of course I would recommend it.

[Midland Retty]

What life safety function do you believe intumescent strips perform? in what circumstances? what type of premises?

[Auntie LIn]

If the seals stop the fire from passing to an adjoining area in less than 30 minutes, isn't that a worthwhile life safety function?

[Midland Retty]

But of course, however based on my experience I'm not sure that actually happens, which is why I keep pressing the issue. And as I said before care needs to be taken by enforcers and assessors alike as to how far they go when pushing for existing doors to be upgraded where they are found not to be of the correct standard.

I also would re-iterate my question Auntie Lin, lets say you go into an office block. The doors look like 30 minute fire doors, but have no markings. Because there is nothing to suggest they are 30 minute doors would you ask the RP to change them all for certified fire sets?

[Davo]

I defy anyone to positively confirm a door is FD when it is not marked

All you can do is tick off the mental checklist

Anyway, all this supposes the frame/surround is up to it

I do however agree that in certain situations then IS is required, ie sleeping risk
 

davo

[CivvyFSO]

What life safety function do you believe intumescent strips perform?

They help hold back fire for longer.

in what circumstances?

In such circumstances that would involve a building being on fire.

what type of premises?

In premises which are on fire.

* CivvyFSO lays the bait and waits patiently.....

[nearlythere]

What life safety function do you believe intumescent strips perform?

They help hold back fire for longer.

in what circumstances?

In such circumstances that would involve a building being on fire.

what type of premises?

In premises which are on fire.

* CivvyFSO lays the bait and waits patiently.....

Here comes a big hungry fish Civvy so watch your elbows.

If we require 30min doors to protect some escape routes why do work around the 2.5 - 3 mins evacuation principle, even when detection is installed?

[kurnal]

Retty they are particularly important where that door is fitted to maintain the compartmentation of a building to stop it falling down on our brave firefighters as they battle to contain a fire (I am talking Building Regulations here not Fire Safety Order).

Elsewhere their value depends on so many other factors- the nature and use of the building, its contents, the life risk and response and evacuation strategy etc.  

We have to have some kind of measure of performance and some safety margins built in. The ultimate test is how many people die in a fire due to a failure of fire doors. Not many. But if we lowered the standard more people would die.

Our standards have developed and been refined over many years and we have a benchmark- BS476 part 22 and 31 in some cases for new doors, BS476 part 8 for older doors and BS459 for the very oldest doors. All were measurable standards. We know that a part 8 door would fail the part 22 test. No matter how good a fit it is. Whether that matters in a real fire or not depends on how good condition the old door is, how the building is used, the evacuation strategy and management etc.

I agree with you that it is wrong  and often futile to automatically require all part 8 doors to be upgraded without consideration of the other factors. The recent case in respect of a historic hotel leads us to think that the Secretary of State is inclined to disagree with us.

Now whilst I have some power to vote him out of office he can put me in prison.

[kurnal]

I defy anyone to positively confirm a door is FD when it is not marked

All you can do is tick off the mental checklist

Davo

Hiya Davo
Is that a new symbol for fire doors in your posting? looks more fun than the old dots.

Did I not show you the Basil Fawlty Knock? Works a treat for me.  

If my clients dont like the knock technique my 100mm hole saw allows close internal inspection of the door construction. I recommend sampling the door in 5 or 6 locations especially near the top.

Hey does this put me to the top of your your mental list?

[Davo]

Hi Prof


Which is of more benefit, IS or properly installed frames?

Here are a few examples from a 2 hour FFS currently being installed (goes instantly grey... (all right, greyer )

http://s690.photobucket.com/albums/vv266/DavoB/?action=postupload

davo

[kurnal]

Frames for life safety I would say. Strange mix of materials in use there. Is that new work going in or is it the stuff you are taking out (I hope?)

[Midland Retty]

I think we are going to have to agree to disagree on this one folks. I still remain unconvinced and care needs to be taken not to over specify or require I/S

Ive already stated many times there are some exceptions where strips are required for life safety.

Kurnal you will admit from your response therefore that I/S are a building protection measure not life safety, and dont forget we are talking about the fire safety order here which only pertains to life safety (including measures for the protection of firefighters in some circumstances)

[kurnal]

I think we are going to have to agree to disagree on this one folks.
Kurnal you will admit from your response therefore that I/S are a building protection measure not life safety, and dont forget we are talking about the fire safety order here which only pertains to life safety (including measures for the protection of firefighters in some circumstances)

Oh no we are not .
Retty you can duck and weave as much as you like there is other fire safety legislation than the Fire Safety Order that covers life safety from fire.  Nowhere have you said that you were only wishing to discuss the Fire Safety Order definitions.

Indeed the Building Regulations 2000 are explicit- look at the explanation in respect of the limitation on requirements on page 5 of ADB which takes considerations of life safety far beyond the "Relevant Person" concept of the FSO. Its the Building Regs table B1 that sets out standards for fire doors.

I reckon you owe me a pint for leading you back towards the straight and narrow.