Notional fire doors

[Eli]

When faced with a fire door with no traceable history or third party certification how can it be referenced in a report?

Would it be OK to say it is a ‘Notional fire door with an undetermined fire resisting performance’. The risk factor would then need to be established and a recommendation made accordingly.

 The concept of notional fire door is in the new guidance for blocks of flats and takes into account historic building standards.

Could a listed door be called a notional fire door too?

Would any of you be brave enough to say it’s a ‘notional - 20 minute or 30 minute fire door.   

[Tom Sutton]

Would any of you be brave enough to say it’s a ‘notional - 20 minute or 30 minute fire door.

In the past I have used the word "Nominal", (being such in name only), to describe such doors, but I would consider notional would to be equally correct, both are a fair description.

As for being brave enough it was certainly done in my day and I expect its done on a daily basis now.

Incidentally there is no such a thing as 20min fire door, Auntie Lin will have your guts for garters.

[Golden]

I use the term of a 'nominal fire door' with a 'notional fire resistance' - I know its quite pedantic! This is one of those tricky issues that I've always considered a dark art of the fire safety world and where there's no real specific guidance available I use my judgement to decide whether the door was adequate at the time it was installed as a fire door in the building and then if it retains its original characteristics and hasn't sustained too much damage or alterations before deciding its continuing suitability. There is also the 'risk' attached to the door and what it is protecting - i.e. what is the probability (guesswork) and what are the consequences of failure of the door?

As for a time period I don't think this is necessary and I don't put numbers to the report. Listed and other doors have guidance available in the English Heritage technical guidance note.

[kurnal]

The references in the flats guidance has its origins in the historic standards. The old BS459 which predated BS476-8 and then itself superceded by BS476-22. Then finally along came BS8214. That leaves us with a whole host of older doors. The old CP3 chapter 4 part 1 from 1962 and 1971 referred to 4 different grades of fire doors T1-T4.

Unless you accept that existing doors in buildings, despite an absence of test data, have played and can in many situations continue to play a fire safety role in buildings then you will create an unaffordable burden on the UK economy. Whether you call them notional or nominal or something else entirely is up to you. Fire ratings are a benchmark. How a particular door of a particular construction performed in a particular BS476 test.

As Golden points out the Heritage groups have conducted a series of tests on a range of different doors and also have tested ways of improving their fire performance. Many such tests were carried out and documented by IFC.  If you copy such a spec exactly then it may be legitimate to claim a fire performance expressed in minutes. Otherwise a comment on whether it is fit for purpose and evidence to support that judgement should be sufficient. 

Golden has it in a nutshell.

[Eli]

Tom

This taken from the new flats guidance, which can not be wrong as Colin wrote it. Plus he did a presentation at the FIA CPD day in which he referred to it in reference to front doors of flats and not internal doors. 

Fire-resisting doors 62.12 under current benchmark design guidance, doors forming part of the protected entrance halls and stairways within flats are normally specified as 20-minute fire-resisting doors (designated FD20). Similarly, doors forming part of the protected escape route from the flat entrance door to the final exit, including the flat entrance door itself, are normally specified as 30-minute fire-resisting doors with smoke seals (designated FD30S).

I am in fact after a ‘cast iron’ caveat. Would notional fire door do the trick when describing a door with no traceability?

 

[Golden]

I am in fact after a ‘cast iron’ caveat. Would notional fire door do the trick when describing a door with no traceability?

The only way is to remove the whole assembly and take it off for testing - hugely expensive and results in a big hole in the wall! As I said in my earlier post there is no way to have a 'cast iron' guarantee of a door's fire resistance whether 100 years old or fitted yesterday, its all a bit subjective and is why we can't rely on a single door. Lets face it most of the critical ones are wedged open anyway - but not when the assessor comes round so you can get your FRA without a problem - and its only an experience assessor that can detect the tell-tale signs of wedging open!

Its also a bit like the nice modern fire doors in a nice modern office block I surveyed on Monday; lovely doors and frames but shame about the gap of about 20mm between the frame and the blockwork - no problem though as there was a nice bit of architrave to cover it up and make a neat job.

[Tom W]

Too true Golden.

Its also worth pointing out they I recently bought some 30 mins and one 60 min door for testing from a large supplier. None of which lasted the required amount of time even though they were sold as 30mFDR and 60.

So these are doors recently bought, hung properly and with paperwork

[Tom Sutton]

Eli you can specify 20FD but do they exist, check out a part FAQ from Chiltern Fire, For economic reasons, manufacturers generally test to achieve 30 minutes and sell the same product for 20 minute applications. Unless there is specific test evidence, 20 minute fire doorsets still require the intumescent strips tested for 30 minutes to be fitted. Purchasers should satisfy themselves that acceptable evidence exists, rather than working to out of date prescriptive solutions. Can you see manufacturers paying for two complete tests when one will do.

One of the definitions of notional is "not based on fact" a definition of nominal is "being such in name only" so I would used the word nominal but does it matter you are never going to get a ‘cast iron’ caveat, lawyers will argue over definitions until the cows come home.

[wee brian]

But what do you do with the wall the door is in? Is that FR? notionally or nominally??

[AnthonyB]

We use nominal for the older style rebated doorsets and old OSRP/FA/FPA upgraded doors & where dout exists.

With structure some assumptions are made from visual inspection only - we have disclaimers that destructive and intrusive testing of all passive elements has not been carried out and where we have a serious concern recommend a survey by a passive fire protection engineer which may include sampling.

[kurnal]

Much of this debate centres round the old terminology of the earlier standard. Remember the term "firecheck" doors- these were 30/20 doors commonly used at the time in flats and as cross corridor fire doors. The "stability" element dissapeared from the BS test and the commercial incentive to manufacture dissapeared with it. Of course many millions remain in situ and  in many cases are as fit for purpose today as when they were installed.

In response to Tom FD20S and E20 doors are still referred to in table B1 of the ADB so a potential market remains.

[Tom Sutton]

In response to Tom FD20S and E20 doors are still referred to in table B1 of the ADB so a potential market remains.

Kurnal my point was you can specify FD20 doors and yes they are still referred to, but can you purchase one. Manufacturers only produce FD30 doors for economic reasons so if you specify a FD20 door it is going to be a FD30 door installed. Some doors are described FD20/30, but they are FD30 doors, consequently are FD20 by default and you must not relax any of the specifications.

Check out http://www.bwf.org.uk/assets/explaining_fd20s_factcard_13.pdf

[Eli]

How does this work for everyone; on a fire door inspection when faced with a fire door with no traceable evidence would the following descriptor be a good caveat?

…….a notional fire door with a notional fire resisting performance of 30minutes. (60)

When faced with a door that is not a fire door ie listed what about this.

……a nominal fire door with nominal fire resisting performance. The potential impact on life safety of this doors nominal fire performance in the event of a fire should be addressed through a fire risk assessment

[Golden]

Hi Eli, if you don't believe it to be a fire door then you can't describe it as such - nominal, notional or otherwise - and only doors that were originally installed as fire doors would fit this description. You would have to have some evidence of its properties based on your knowledge and experience otherwise you don't accept the door as having any fire resistance beyond a few minutes. Its not about the listing of the property or doors, I've recommended listed doors to be upgraded and this can be a very expensive process requiring skilled craftsmen so not to be undertaken lightly.

Where you do have some evidence I would personally describe the door as a 'nominal (i.e. in name only) fire door with a notional (i.e. based on theory not on reality) fire resistance'. I would not put any time standard on the description even if it was a relatively good door in a sound frame.

If the thread is more about doors in listed properties then you will need to read the English Heritage guidance notes which give good descriptions on how to assess and upgrade doors.

[Eli]

Hi Golden

I am trying to get together two descriptors that could be included in a report on fire doors as a functional piece of fire safety.

I see three distinct categories of door/sets

1 the door with evidence
2 the door that looks feels and smells like a fire door but without evidence
3 the door that just isn’t a fire door.

Based on the two definitions used by Tom I would assume that the door with evidence is a factual description and can therefore be named FD30S or whatever it may be. Piglet makes a good point but in a legal case this would stand up I am sure.

The door without evidence is a fire door but not based on fact ie Notional and therefore if it was in a hole in the compartment where an FD30S should be, it could be described as such; a Notional (not based on fact) FD30S or whatever it may look like.

And the 3rd type is in name only a ‘fire door’ as it will prevent some flame some smoke from getting past for an undetermined amount of time ie nominal (in name only) FD with nominal fire resistance.(in name only) I guess this could be described as ‘not a fire door’.

The last may be a danger to life safety, the second may not last the designated time and therefore may impact on escape strategy/life safety and the first one should perform at the level it says it does.