¶ European Fire Safety Engineering
Hello everybody , welcome to the Fire Science Show . Today we have a big chunk of history of European Fire Safety Engineering and a bit of the future , a small step towards the future hopefully bright future of European Fire Safety Engineering .
If you've read , I can say famous paper by Angus Loh and colleagues on the rise and rise of Euroclass system , it has painted an image of overly powerful group of people who are setting up the European legislation in terms of Euroclass a lot of politics and interesting background stories on how the Euroclass system was born .
I've invited today one of those overly powerful people . His name is Rudolf van Mielow . He is with DJMR now .
He was with Effectis and Tino back in the days and Rudolf was one of the drivers of implementation and development of the SBI , the Single Burning Item Test Standard , which is used all over the Europe to assess the middle Euroclasses for many , many products . In this podcast episode I have a chance to discuss the rise of the SBI standard with Rudolf .
What was the background back then , in the day when the test was standard was developed ? How did they approach it ? What was driving the design choices behind the standard and how did it look to actually introduce a pan-European a truly pan-European standard method In practice .
We're discussing the round-drop ins , we're discussing the calibrations , we're discussing challenges of introducing oxygen depletion calorimetry . So a lot of technical stuff , but also a bit of politics and a bit of kitchen how stuff like standards are developed .
And for the future part , given 20 years of practical use of the SBI method , given all the experience with how the method was constructed and implemented , we take a look at the facades . We know that facades were next to be standardized , which kind of did not happen . Today we're working towards a pan-European large-scale test for facades .
But Rudolf is bringing an important cause for an intermediate-scale method and towards the end of the episode we have a chance to discuss it a bit . So a lot of history , a bit of refreshing new thoughts . For me it was very interesting . I hope it will be as much for you . So , yeah , enough talking , let's spin the intro and jump into the episode .
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This year , get in touch at OFRConsultantscom . So hello everybody , welcome to the Firesize Show . I am today joined by Rudolf van Mielow from DGMR . Hello , rudolf , good to have you in the podcast . Hello , wojciech , and what a professional career you had .
I know now you're with the DGMR , but I recognize your name from the years in TNO and I know you've been also a part of Effectus and it seems you've also been dealing with this overly powerful organization called EGOLF .
I'm really happy to have you in the podcast because for a long time I have brainstormed how to approach the topic of European standardization over the single burning item tests and I know you've been kind of involved in that one .
Yes , even more than a kind of involved , I think .
That's what it was said in the recommendation letter . Anyway , because Patrice will kill me if we don't plug it very soon , I will be also very happy to meet you in person in a month from now , because we're meeting in the Netherlands for a very interesting conference held by the DGMR on 21st March at Zinger Museum in Lauren in the Netherlands .
Let's maybe first plug in what's the conference about and what we're going to do there . Really happy to be there and speak about green façades in this event .
It's a conference about partly fire safety and partly sustainable future , and especially the mix of those two , because we use more and more bio-based materials , especially insulation materials in façades , for instance , and of course there is also an influence on fire safety .
My own presentation , with a colleague of mine , will be about the fire size , but you also hear several presentations of the more sustainable part .
I saw the speaker line up . I'm a part of it . I'm looking forward to that conference . Even on sustainability in Slovenia at the end of last year was accident . I hope this one is as well . Anyway , let's go on to the topic . You have extensive history of basically building up the SBI standard and then implementing it , round-dropping , testing it .
Then you had a chance to use the standard for many , many years . Now we're 20 years after it has been initially introduced to the market , used by many laboratories . We know the strengths , we know the downsides of the standard . I guess there's a lot of lessons for the future and it seems we struggle to define new pan-European standards .
I am actually quite fascinated how a truly pan-European standard could have been developed . In the paper there's this sentence that no set of existing methods was both politically and technically acceptable . I would never have thought about political acceptance as a criterion for testing method , but perhaps that's the trick .
So tell me , what did the landscape look like those 30 years ago when the effort was started on defining SBI , and why did we need a pan-European testing method ?
It's about barriers to trade . The reason why originally the CPD and later now the CPR developed is to take away barriers to trade , and for that it is important that… Wait , take away .
Okay , take away . Take away from some , put on the way for others , I guess .
Of course there are positive and negative in that , but the original reason was to take away barriers . It was not very uncommon . It was even common that if you did one test in one country , another country people didn't believe that that was enough proof .
So you had to do the test again in their national laboratory and in the third country and the fourth country again . So it's not so easy to sell your products over the whole of Europe then . So we needed an harmonized test standard .
That's just a clear reason . So Poland at that point was just outside of communism and we were still decades to go to join the EU . So I guess , comparing for example , poland and Netherlands , countries with completely different histories , even the forms of government were different .
So you can expect that Polish standards would be vastly different than the Netherlands one . But you're in the heart of the Europe . You would say that , for example , products tested in Belgium would not be allowed in Netherlands or Germany .
Yeah , it was a big difference what was allowed in one country and allowed in the other one . I think that the difficulties and a lot of people don't know that the performance of products , of facades or walls or floors or whatever , is very dependent on the fire scenario that you use .
And actually the different test methods in the different countries use very different fire scenarios and different heat exposure , different radiation convection conduction . So if you compare the different national test methods there were , in one country a product would be good and in another country it would be bad .
Of course there were also a lot of products that were good in most countries and bad in most countries , but there were also a lot of products that were very different , performed very different according to the national test method .
And in terms of general trade , was it like today ? The trade was free between the countries In European Union . You were a producer in Netherlands , you could sell to France . How did the barriers look there ?
You could sell everywhere , but you had to prove in every new country where you arrived that your product performed okay according to the national standards , and of course this is sort of barrier .
And then even locally there was an additional barrier that a lot of local people stopped the product there because you had to test it again somewhere in a part of a country even .
Okay , that's very interesting . I remember similar things happening in Poland when we were joining EU and how our system was , let's say , migrated into the Euroclass system . By the way , the Euroclass system that was developed much before the SBI .
I've read in some of your papers that it was around 1993 that this Euroclass classification system where we assign the classes from A to F in the European system , A means the best , F means the worst , but tested In the outlook of the Euroclass method , there's a range of methods from small flame to a fully developed fire test and there was a need for an
intermediate method . That's how I've read the origins . Why SBI efforts ? How did the intermediate level look the moment you started working on SBI and what did you take to start with ?
Before the European system started the reaction to fire , several countries decided what the principal essential requirements were that a product should meet , and fire safety was one of them . Second level , what essential things in fire safety should be dealt with . And when that was decided , it was clear that the reaction to fire should be based on several scenarios .
And then the discussion starts what scenario to use ? At the top is clear a fully developed fire . What is the contribution in a fully developed fire ? Ignition also clear . You use a small flame and that's the first start of a fire .
Something in the between we could call it intermediate was an area where a lot of test methods existed , as I said , not correlating very well , and this is an end statement . So we needed one new test method . No , we needed one test method .
It doesn't have to be new , but if you use a test method of one of the countries , there's a commercial positive effect for that country , and every country , especially the bigger countries , wanted there to see something that's equal or nearly equal of what they had before , and so there was a decision to make a new test .
So everyone is in the same bed position . You're talking countries , but was it really truly a country representation , as in governments , or perhaps that was representations of industry , like who are people that were deciding In ?
principle , be aware . In principle , there were countries , there was a special group started , the fire regulators group , that had to discuss the issues about fire safety .
But because most civil servants don't have in-depth knowledge about fire safety , most countries ask an expert in fire safety to come with them in the meetings and in fact , because it's such a specialized area , the experts had a lot of influence on the discussions and on the results .
There's a paper by Angus .
Yeah , yeah , yeah .
It kind of goes into the fun parts of that process . Perhaps if the listeners have not read this paper , which should get some sort of like Pulitzer award for fire , then you should read to
¶ Fire Testing Methodology Development and Implementation
that . But let's focus on technicalities . So you had to base on something . What did you base it on ? Did you have a method that was the closest to SBI and worked it ? All the words ? Or you have said , okay , we need a corner and let's start with the corner .
Yeah , in principle we need a corner . Even that was not the principle . What fire is possible in small deans ? And when you look in the room , when is the wall attacked most ? That's in a corner position . So therefore , we started with a corner position in the small room as the scenario that we had to represent .
Of course , on a smaller scale , it was possible to use a room corner test . That is a lane and it has a corner and it has a corner of course , but that is on a scale . You can use it , but the costs and the size and the costs .
So room corners was 2.4 by 3.6 out of my head , if I'm not true 3.6 , 2.4 and height also 2.4 , 2.4 weeks and it requires you to line the entire room with the material . That's right . So that's ? We're talking about like 20-something square meters of material that go per single iteration of the test .
It takes like what an hour perhaps to run a corner , Depends how bad your material is .
You are , but the time you need for the test is not so important . It's the time you need for installing everything and then taking everything out after the test . That's much more time than the test itself .
So realistically , on a good lab you can do one a day , more or less , yeah , not more . Okay , you knew that corner setting , like in room corner , is kind of representative . In room corner we have significantly larger fire than SBIs . So how did you ? Came up to the source 30 kilowatts in SBIs . You said it has to be representative of something .
There were already tests in the different countries , especially the tests used in the larger countries . There was a lot of political pressure Depends of these test methods . In the SBIs , for instance , the maximum total heat flux of what is it around 40 kilowatts per square meter was not compulsory but was a goal .
And that's exactly the maximum heat flux that is in the SBI just near the corner behind the flame . So it was developed in steps and a lot of steps . Of course , a radiating source also used . But if you need a radiation source that is producing 40 kilowatts per meter on a specimen , you need to place it very near the specimen .
First , you can't see what happens with the specimen . Then that's one . Secondly , what happens when parts of the specimen come down or deform or whatever , and come against the radiating panel ? That's not what you want .
Yeah , okay , more details why it's closed in a small compartment box . It's a part of the standard . So , even as I've decided , we are closing it in some sort of compartment , right ?
Protection of a reparator nothing more , nothing less .
Also , prevention of external effects like wind and stability of the .
Yeah , that depends on where it is . Of course , in the laboratory Also , without that protection you can have very low speed of flows . But when in a small room you can organize that much better .
Why no roof above the sample ? That's another technical detail that's quite enriching , right .
We investigated a small ceiling on top , but the results were then more variable and you then need , for instance , a larger hood .
Well , there are a lot of practicalities to limit the size of the test method , gather good repeatability and reproducibility , and there are also more political and commercial reasons why a test is limited , because the costs grow when you take a bigger size of a test . So the ceiling was investigated but almost at a moment decided not to use it .
But it's a bit silly , because a wall , a fire along a wall , is quite different from a fire against the ceiling .
Yeah , of course , of course . I mean it's interesting , and perhaps few decades later , when the test is used for things that it perhaps was not perceived to be useful , it's interesting that those details are not there in place .
I mean , in the end , right , I often say that fire testing is the science of logistics how to put as many samples and burn them efficiently in the lab without making too much mess . In here you've ended up with quite an elegant system . You open the back , you put a corner that's already built on two sheets of whatever material you use as the backing .
You place them on a spot they fit . You don't install devices on it . You have the burner there already when the test is done . Open the back , throw it out , put the new one . Yeah , it's efficient , it's very efficient , I think in my lab .
I'm not sure how many we can do , but I'm quite sure my colleagues could do a dozen in a day , at least on a long day .
That is a bit difficult if the product gains because the temperature outside the test has to be . Yeah , sure , Very alone . Mr Schirru accepted .
But still we are very far away from a single test that you could do in the room corner , and you perhaps don't need the firefighters' assistance for every single test you make . No , that's also a benefit .
Sba method is not just the source , it's not just the compartment or the setup , it's also the measurements , and this test has heavily invested in oxygen-chlorimetry and other measures related to the production of smoke and toxic species of the fires . So tell me how that part was defined . How are you going to measure this fire ?
A very important starting point is to limit the number of visual observations . Of course . Many people that have experience in a laboratory know the endless discussions between different operators when viewing a test and viewing a specimen after a test . Were their flames consistently or just for a short time ?
Is this a piece of damage on that part , or is it not damaged but just soot ? Or is it deformed or is it not ? That's a rather terrible way of interpreting those results at the end . So we try to measure as much as possible .
The oxygen-releasing method so counting the amount of oxygen molecules that has been used by the combustion , was a technique already there for two , three decades in the more research organizations and became more widely available for the labs . It was , and still is , a rather difficult method for new labs to cope with .
That's clear , and that was one of the problems at the beginning . That was , for instance , quite clear in the first round , robin .
In the 1990s , where you were implementing this or developing this , cold calorimetry was already a tool that was widely used , or I think cold calorimetry was also entering this sphere by then , right , it was only used by a few laboratories .
As I said , more research-type organizations and less in the more commercial laboratories . And especially these laboratories . They had to introduce the oxygen-releasing method and the new SBI setup and do the first test in a very high-speed pressure cooker , because everything had to be done in a very short time . That was difficult in the first round , robin .
That's why one of the reasons of that is that we did later that's , I think , a second round Robin .
What was the reason for the speed ? The European legislation , the need for the new method ? What was driving it ?
The request for a new test method started six years before . So at the beginning and when the development went very , very slow , a lot of discussion and at a certain time the principles were agreed , the principles of a propane gas , vernier corner configuration . But then the standard has to be tested .
Of course you need to know what repeatability and reproducibility is of a test method and whether all types of products give a sensible result in the test . You don't know beforehand . We now know what we can do and want to do with that method , but you don't know beforehand and the time was very limited .
So I was the convener at that moment and I put a lot of pressure on the labs to produce results . If we had taken two years instead of half a year , maybe the quality would have been a bit better , but my experience more afterwards than before , that is that if you give the laboratories more time , they only start later .
Sorry to say yeah , yeah , yeah , you're speaking truth , man .
I agree , that's how it works . Everyone is busy and I know there was also a concurrent study in comparing SBI to Roomcorner , like using SBI kind of as a predictive way . What was it after the implementation , or was it already something that helped you define the method as itself ?
It has been done After that the European system had been built . But to get the right criteria , the class limits , comparison between the SBI and Roomcorner test results were used . But that was after the actual development of the SBI method . Then you can .
So setting the levels of the ladder .
Setting the levels , of course , commercial , very important criteria the limits for the different classes .
Fantastic .
¶ Fire Safety Testing Standardization and Validation
So let's go back to the measurements . Can you briefly explain what is measured in the SBI and how ? Mainly heat and smoke .
Very simple Heat and smoke . Heat in the sense that the rate of heat release is measured and the speed of which the rate of heat actually grows at the beginning . At smoke the same , the amount of smoke and the speed of which the smoke is produced at the beginning and then a lateral flame spread to the end of the specimen .
But that's nearly never , never important as a class decider . Going back to the first two , in heat the total heat release is in the first 10 minutes of the test . The test as a whole is 20 minutes and the speed of growth is in the FIGRA index fire index growth rate . And for the smoke the same .
You have a total smoke production and the smoker also to smoke . In reality , both FIGRA and Total Eterlis can be the desired in a classification . It depends very much on the type of product . You know from certain products that the FIGRA will be decisive for the class and all the types of products . Whether THR will give the decision .
Interesting because it will depend on , for example , material density , how much heat you can emit from lightweight material . You will eventually emit less heat than from the same material . Okay , if you have found material , it's going to weight less than the same material in solid form , but the rate might be much quicker .
So I kind of like you know , separating the total production and the growth rates , how much in the end and what was the fastest rate it was burning . It's kind of interesting because it gives you two different point reviews . Was there any specific reason why a 10-minute window was chosen ?
Yeah , it was very basic . You need a good repeatability and reproducibility , especially in the second half of the test . The variation in , for instance , deforming , delamination and so on of the product causes a very large variation in results .
so not so good repeatability and reproducibility , Okay , and now how to make sure that you burn a board out of polyethylene and you burn it in my lab . You burn it at TNO . How are we sure we are getting the same figure ? Because it's quite sophisticated method of measurement .
As you said , implementing oxygen calorimetry is challenging on its own , but here you also have some optical ways to measure smoke density for Smogra . So you have to capture the velocity in your duct . I mean to start off with . The ducts have to be the same in standardized .
To what extent do you want to actually make sure that those tests are done the same in all labs ?
We started by producing the several SBI facilities one position at one place . So the apparatus then is the same and there are a lot of checks in the standard to know that , for instance , response time , delay time , are within certain boundaries .
There are several calibrations exactly doing that , checking whether the system performs as required , especially the oxygen-replenient method .
Okay , and then the most impressive part of this project for me , the round robins . So I mentioned there were two of them . Tell me what was the design principle of the round robins and how annoying that was the round robins itself .
Round robins are often very annoying . If everything is new for everyone , you know that beforehand , so it will never produce an optimum result .
Basically , what you measure is a repeatability , that is what the difference is between the same tests directly after each other at the same place by the same people , and reproducibility , which is different tests in different laboratories by different people on different apparatus . If these two have a small variation , then you know you have made a good standard .
¶ Fire Testing for Euroclass System
There is some special thing in it . You can't give too much instructions to people . Why not ? Because the standard has to be self-explaining In the future . When you design the method then you think in the future people have to read the paper , the standard , and had to know what to do to do the test .
And if an round robin instructs people what to do , that is additional information . Then you don't know what repeatability and reproducibility of that standard of paper is . So first you have to check the apparatus , whether everything is installed . You can see that we asked in several steps all the laboratories to send in their calibration results , for instance .
We checked whether everything was okay and then they had to do the test on these large set of materials by themselves , without us telling what they should do better , or maybe it was okay what they did , but we couldn't give that instruction .
Was it connected with accreditation process ? You could promise them they will be accredited after that if they pass . No , no , no .
You're not testing the laboratory , you are testing the method . Everything is done anonymous . So only the coordinator of the round robin knows afterwards in report which laboratory has produced what results . So you only see laboratory 8 producing this test results and laboratory 15 producing that test result .
And to what extent the rigs were identical . Like were they built by the laboratories ? Were there one supplier that supplied to the laboratory ?
There was one supplier . So that was the reason to limit that variability , not to ask people also to defend their own apparatus from the drawings . But it was produced , everything was producing , and that was the first set of SBIR apparatus . Of course afterwards there were two . I think there are two or three sources , main sources of SBIR apparatus .
Super interesting , and the materials that were chosen were the representation of like the scatter across the euro classes , like from non combustible boards to like extremely flammable foams . How did you pick them ?
We tried to pick them as the products that would end up in the intermediate classes , but of course you don't know hard , so there were also a bit too good materials and a bit too low performing products , because you it's a new test method and you don't know where a product will end up .
As I said before , the different test methods used in different countries produced very different results , so it's very difficult then to say what will be . The performance is in a quite new death method . We had an idea , but at the end it didn't end bad . I think there was a good spread over all the classes , but it could have been better , of course .
So the repeatability was assessed in the end in how consistent was the class assigned to a product after the test ? I guess Right ? Or you were comparing those to the raw results like figuras , smogras of them .
The NTT had the role to make all the repeatability and reproducibility calculations and these figures are produced then in the standard and one of the NXs . In the standard the repeatability and reproducibility is mentioned .
Okay , now you have a time machine will leave 20 years after this is implemented . The entire Europe is using it . There's probably more than 50 , maybe even 100 , sbi rigs across the Europe being in a daily use . We've moved entirely into the Euroclass system , for good or bad . I don't know how do you view the process from today .
Like I understand that you were working in a very specific circumstances time pressure and everything . Any fundamentally different decisions that would have been taken today if you had a chance to redo the process ?
I think a special requirement to produce the performance of a product in and use application is very , very difficult to do in practice . The range for that are very limited in the standards . You have a sort of a cafeteria behind that the product of 40 millimeters or 80 millimeters or whatever .
I think that could have been done a bit better , but okay , you don't know by heart at that moment . Important is , I think that afterwards the SBI was used as the determining test in the mid classes for a lot of more five scenarios than in fact it gives good information , for instance at the Facades . Let me take one step back .
Before the European system was developed , the important scenarios were selected . I think there were 12 , 13 , 14 . And a few of them we see in the Euro classes . You have a fully developed fire , the A1 , a2 tests , all non-compensability and color-reflexibility . At the bottom you have the small flame . In between you have a room corner and a corridor scenario .
The corridor is only by radiation and that's a flooring test that's used for that scenario . But of course you have a facade , has a quite different combination of radiation conduction , convection . You have shafts , you have ceiling voids , you have staircases . In fact , to get optimum information about these scenarios .
You need to do other tests , but in fact that would mean that the producer would have to do a lot of tests for all the scenarios , and that's what was not what intended . Your committee wanted to introduce a new system that was not a heavy burden for industry , so the number of scenarios was limited , and the first one to be added would have been facade .
We discussed about that , as facade was left out , because nothing happens with facades .
But we are talking about 1990s facades , right ?
We are talking about facades as they were built 30 years ago , not a facades we are building today . That will always be the case . We don't know what buildings we make in 20 , 30 years , and maybe addition to test systems will be insufficient , because we know then that something else is very important . We don't know yet . That was the same 30 years ago .
So , if I understand correctly , the SBI is good as it is , while it is used as intended and where it deviates more and more from the intended fire scenario that SBI represents as some source of fire in a compartment to a material that's predominantly a wall material . So let's say we go into a facade scenario
¶ Fire Testing in Facade Construction
. In facade scenario the way how you ignite facade is most likely through fires bending from your windows , like rolling over from compartment that is on fire onto the facade , or from a large external source like a trash or something that's stocked against the facade . In here it's not a flame touching the external surface of your system .
It can be something that's actually attacking the cavity or the gap from between , from underneath the facade . I should be reading . It rolls out from the wind and we all understand the people who are doing the fire testing . We all understand that it introduces a completely different exposure to the thing tested .
Even if you take the most simple case , take a piece of a paper and try to ignite it through the middle of the page , you can put a flame against the middle of a piece of a paper for a few seconds , but if you do the same to the edge of the paper , it will immediately catch fire . That's how ridiculously different those most of exposure are .
So the fact that the material has achieved Euroclass B in SPI system is in no way an indication that it is material to be used in a facade environment . Before I let you go , even struggle in scenarios where you would also have a strong force ventilation flows .
I had this issue in Poland in some tunneling projects where the lining of the tunnel for the creative means would be built from Euroclass B materials . I mean , that's great material , right ? Euroclass B right , it's fantastic .
But we're talking about a system where you have forced ventilation , high velocity flows , like completely different mode of heat transfer , then a free-standing flame in a compartment . It's a completely different setup , right yeah that's quite different .
It's such a different setup that don't trust a B-class material . Be aware that B-class materials are good . In a room , corner configuration , there's also furniture , where there are also other things that can burn . Then there's another level of performance required .
Then on a large facade or in a tunnel , there's a very good reason then to say this might be non-combustible or nearly non-combustible at a CY , a CY class A2 or A1 .
Yeah , but I'm bringing that as an example that the end use , the way where the product will be used and the fire scenario which will be the natural scenario for that product in that application in this particular building , is something that goes beyond what the project or whatever we are discussing here . It goes beyond a simple class .
It's difficult to assess a number or a letter to a material and tell it whatever you do with it is going to be fine , right .
Yeah , but be aware the examples we just used , for instance the tunnel you can use a higher class in the euro class system . Normally I wouldn't say that when I compare with lower classes , but the two highest classes are more material tests than tests . That end use is important . So non-combustible or nearly non-combustible is yeah .
The euro class is a good representation of what you want with non-combustible .
Yeah , sure , I mean , yeah right , it's difficult to design a bad product with non-combustible materials at all . Now so if we agree that the method we are discussing today , the SPI , is not perfectly representative for facade systems , we are currently ongoing through this definition of new pan-European standard for facade testing .
Again , a very large testing methods , two countries that would like the method to look just like theirs , for reasons that you perhaps have mentioned in the beginning of the episode . I mean , it's kind of funny . It looks exactly the same like what you've said .
But I know that , and it's something that you also brought to the table the need for an intermediate method . Again , we have material testing for the materials that are used in facades . We have the end-use full-scale large testing method . Again , the same issues long procedure , very costly . You can do only a few in a month .
That's even more difficult threshold than room corner . It seems that the intermediate method would be very well received by the industry . What's your opinion on ?
that . Yeah , my opinion is that we need intermediate test methods . At the moment there are several countries that stepped from a B-class for all sorts of facade 10 years ago to an A2 class or a large-scale test , and then a large-scale in the sense of a British standard A414 , part one , two , or the DIN German 4102 , stroke 20 .
But that's the size that it tells me . This way , the SBIs is not a big test , but I know that in a lot of cases practical cases where you design a building , performing the SBIs test is already not so well fitting into the building process . Let's put it that way .
So in the vast majority there is no test done on facades of a certain building , but it is compared with something that's nearly equal and it has a well , has a known class .
If you introduce a BS test or a DIN test for every part of every building , then the cost will be enormous and that may be reasonable to ask for , but only in a high-risk situation , and there are a lot of situations in between .
So if I look at what happened in Europe in the last 10 to 5 years a lot of countries changing their legislation to A2 or the real large-scale tests we did a research for our ministry , which would be something for the Netherlands to do , we couldn't find a good risk-based argument for that big step of performance .
Those were political arguments , not risk-based arguments . So we propose in the Netherlands to the ministry to take a smaller step and have the other large test method to BS and the DIN as another possibility for maybe high-risk situations , but for the majority of situations to use an intermediate-scale test .
¶ Facade Fire Testing Methods Comparison
And currently , as you know we talked earlier , we are developing an intermediate-scale test at the moment .
There is this ISO test with a linear heat burner that is put directly underneath a piece of facade that's I don't know , 2 meters tall , in a corner configuration . I kind of like that test . It's actually quite brutal , to be honest , that test , and in Poland we have something that I would perhaps even consider an intermediate-scale .
I think we always considered it as a full-scale test in Poland , but to the rest of the world it looks basically as an intermediate test , the one where we have 1.8 meter wide by 2.5 meter tall sample and we put a woodcrip against it and it's tested three times , each material three times , and it has wind component into it .
So we're pushing the fire plume towards the facade through the wind and it's quite , I would say it fueled local certification . It was developed in Poland in 1980s in my institute , long before me , and till today it's still doing quite a good job in filtering out good from bad . You know it's .
I mean I cannot quantify the fire behavior of a facade with that test to the level I could with BS test , for example .
I don't have that much data from it , but I've never seen a material that would pass the Polish test and be extremely horrible in , you know , in larger test method , like I've never seen such thing and ventilated facades with combustible materials in them . They fail miserably in our test and you could use it like in Poland .
It's used for giving classification to products , which is requirement by the local code , but I could see it being done as a screening test . You know you have you introduce a new material to the market . First material tests non combustible , combustible . Yes , we have combustible . Okay , here's your intermediate method . Let's see how bad the configuration is .
It's not bad . Maybe you can stop . Then it looks dangerous . Okay , if you want to put it into the market , you need to have a proof from the full scale test . I think that's a quite reasonable pathway . What do you think ?
We choose the isotest you just mentioned , the 13 785 stroke one as a basis that we revised it considerably . I had a quick look at the Polish test and I can give you the reasons not to choose it . Okay , At that moment the isotest was our first choice . So I was looking for test methods that were better not the same performance .
But and I had the impression that the Polish test wasn't that because of several reasons .
First , the attack on the cavity , because the in a Polish test the woodcrip is in front of the facade , not under , and with an outer layer in the facade with hardly or no openings , the flame won't go into the cavity very fast and we wanted to have the exposure of the cavity at the bottom side , as if the flame comes out of a ring .
Secondly , if there was a choice between an international test and a national test , we preferred an international test just to keep out discussions , to have one country in favor and not many other countries using the same method , and when you use or choose an ISO method you don't have that discussion and I was willing to start revising the method .
As far as I know at the moment , they will follow completely or nearly completely what is now changed . They were revised by our Dutch project , because the major change we made is especially the oxygen-replenient method . I think that the more modern , the more sophisticated method produce more measured data .
You can get much more about the performance of a product than by only visual observation or by temperature measurements . Even there were a few other things . A wood grip is not so constant in heat exposure as a guard so , and the Polish test had a wood grip so yeah , so I brought up the Polish , not as a proposal that should follow .
I'm just giving an impression that an intermediate test can be in a country's low system for 40 years and be quite successful in fulfilling this particular role of being the filter of bad from good . In terms of our test I also there are parts I don't like from it . I don't like the grip for sure .
I like ISO gas burner much more , and then it's definitely more reputable and it's easy . You can turn it off any moment you want . There is no uncertainty . Well , there is minimum uncertainty related to operation of the burner and the gas in Poland will be the same as in Finland and the same as in Spain .
If you use propane , for example , and for a crib , we know that in our crib that's a small crib , but if you go into the BS crib inside BS compartment you can have from two to five megawatts with the exact same crib . That's massive . I like the wind as a boundary condition on the test , like .
I think wind is something that really changes the outcome of the test . And what you said about cavities as long as there is a gap , as any vertical or horizontal gap , having wind present in the test . I find it quite reliable against ventilated façades .
But wind prevents you from oxygen calorimetry and wind also introduces a new health and safety challenges in the lab . So if you subject the façade to the wind it's very difficult to collect all the smoke with the hood . So the smoke fills the entire compartment and it's quite big . So health and safety here , which we know is nasty , definitely a lot of space .
I mean I'm very interested in the outcomes of what you propose to your government and I'm looking forward to seeing how we could internationalize that and where we could go . I think it's also something that could interest . Is there any ? I assume it's your local country endeavor or is it related to the European Commission and the large testing method ?
No , we are now developing it in the Netherlands . But , as I told earlier , our proposals are also sent to ISO and they have been discussed in ISO , a working group too . But if I don't know whether people know what size it is , it's the same size as the Polish test , 2.4 meters high sample .
It's a corner configuration , not flat , but a corner configuration 100 kilowatt burning line , burning under the large wing , Okay , and gas burner . So that gives a good idea . There are 10 thermocouples in the specimen , in the in front of the facade and in the cavity , and the most important thing is that the Hutter Buff .
With the Hutter Buff we measure the oxygen with the oxygen depletion method . So you know to know the eaterlies .
Very interesting development and I guess we'll be able to talk more about that on 21st March in Lauren , the conference for which everyone is invited , and for this discussion .
Rudolf , it was a pleasure to have you in this show and perhaps some final words for the future designers of the test methods , Like one wise word of a person who developed and implemented what should they look for ?
Try to know and to get being informed about the background of test methods . What is it testing ? Why is it tested that way ? Because in a lot of cases in most cases even not the exact product as tested will be attached to a building , but something that's nearly equal and everyone should dive into .
You get knowledge about what the influence is of these differences . It was only then , and then you will have safe buildings in practice Fantastic .
Rudolf , thank you very much for coming to the Fire Science Show and I am looking forward to meeting person in Netherlands . Thanks , okay , okay , thank you , okay , thank you . Thank you , wojciech , and that's it . Thank you for listening . I hope you've enjoyed it . There is quite some reading resources for you if you wish .
I've linked as soon as Angus Laws paper on the rise of the euro class , I've linked Rudolf's papers on the development of SPI and I've linked our Kresnik study on the Polish test method for FASA so you can take a look by yourself on how this looks in assessing performance over a large number of different FASAD samples . A lot of interesting things .
And there's a chance to talk to me and Rudolf in the Netherlands and in just a month . So I'll also link the conference website . If you're listening and you're in time and you're not that far away , you feel yourself invited .
It looks like a fun event and I've heard Angus will also be there , so you can take a copy of the paper on the rise of the euro class and perhaps get an autograph . Anyway , I kind of thought with the thoughts where to put this interview with Rudolf .
I thought maybe we should put it in the experiments that change the fire science , but it's not really science . It's something that changed the engineering .
I've decided to keep it as normal podcast episode , but definitely programs like this , developments like this , where a bunch of people get together in a room , they define a standard , then everyone works towards round robin , everyone works towards the calibration . Then there's a massive effort to compare this with a room corner facility .
Even nowadays people are making PhDs comparing cone calorimetry with SBI , with room corner tests . It's still in use . It's still still today . New ways of using this method are being introduced , and that's that's really interesting . That's beautiful in fire science . This , this thing's never stopped .
There was also an interview with Biggit Messerschmitt , which I also link in the show notes . She was also part of the program when they were comparing it with the room corner test . We also discussed testing regimes , testing methods , and I think it's great counterpart to Rudolph's interview .
If this one interested you , I'm sure the Brigitte's one will be very interesting to you as well . So with this listening recommendation now , I'll just stop here with this episode . Thank you very much for being here with me and I am looking forward to see you here next Wednesday . Take care Bye . This was the Fire Science Show .
Thank you for listening and see you soon .