Grenfell Tower Inquiry - Expert Evidence - Prof Purser (29 November 2018 Pt 1 of 2)
00:00:04 you
00:00:24 you
00:06:41 good morning everyone welcome to today's hearing today we're going to hear from another of the inquiries expert witnesses yes good morning mr. chairman
00:06:53 witnesses yes good morning mr. chairman our witness today is going to be professor David purser but before I call professor purser can I just explain what we're going to be doing today he will
00:07:06 we're going to be doing today he will begin his evidence by giving a presentation setting out what what he has all the work that's come gone into
00:07:17 has all the work that's come gone into his phase 1 report which has been circulated and published the presentation is in three parts and for each part the professor has prepared to detail slides to which he will be
00:07:28 to detail slides to which he will be speaking if I make her these slides contain images including diagrams of flame ingress and smoke production photographs of the tower and also fire damage in other buildings because of the
00:07:42 damage in other buildings because of the nature of the professor's work he will also be talking about the impact of toxic gases on people that might be distressing me that is exactly it so what I want to do I will give a shorter
00:07:54 what I want to do I will give a shorter warning as we go through the presentation but I want to repeat a warning now that we've given on previous occasions that some may find the contents of the slide and indeed of the presentation itself distressing all
00:08:05 presentation itself distressing all right well thank you very much well people if people fear that they may be upset by what came to Duchene and they can of course leave and they can leave it anytime that they feel that's appropriate
00:08:16 appropriate thank you sir can I now call professor David person yes thank you
00:08:40 I swear by Almighty God that the evidence I shall give shall be the truth the whole truth and nothing but the
00:08:53 the whole truth and nothing but the truth
00:08:54 truth me thank you very much professor they you prefer stand up to give you all standing up yes sir good morning
00:09:08 standing up yes sir good morning professor morning could you confirm your full name for the record please I'm David Anthony person and can you confirm that you have provided a preliminary
00:09:19 that you have provided a preliminary phase 1 report to the inquiry which is dated the 5th of November 2018 uh-huh can you also confirm that you were asked in that phase 1 report to address 3
00:09:31 in that phase 1 report to address 3 matters firstly the production of toxic gases in fires similar to that at groennfell tower and the consequences of inhaling toxic gases in such circumstances both physiological and
00:09:43 circumstances both physiological and behavioral secondly the toxicity when exposed to fire of certain materials which were present at Grenville tower and thirdly any recommendations arising
00:09:54 and thirdly any recommendations arising from those two points that I've just set out including us to any further testing which ought to be carried out which is relevant to the issues yes is it also right that you were asked to set out
00:10:06 right that you were asked to set out your preliminary conclusions on again three matters firstly the production of toxic gases and consequences to occupants of different generic fire scenarios and conditions occurring in
00:10:18 scenarios and conditions occurring in fire similar to those likely to have occurred at different stages and locations during the Grenville tower fire
00:10:25 fire secondly the likely causes of incapacitation and death at Grenville tower including those whose bodies were consumed by the fire and thirdly the possible toxicity performance of materials present at Grenville Tower yes
00:10:39 materials present at Grenville Tower yes it is important to note before we continue that you have also been instructed to provide a further report at phase 2 which will address the masses that I've just listed but which will be
00:10:50 that I've just listed but which will be updated and expanded as necess yes you have confirmed and said in your report that it is a preliminary report
00:11:02 report that it is a preliminary report and you intend to conduct a more detailed analysis in your face to report that's right that's an important point so it is is it right therefore that the views that you express in your phase 1 report are professional yes can you
00:11:16 report are professional yes can you confirm that the statements made in that report whilst provisional are true to the best of your knowledge and belief to the best of my knowledge yes and can you also confirm that you've provided this
00:11:27 also confirm that you've provided this that the that you've provided this report in the same way as you would have provided provided a report to the court yes can I begin then just by dealing
00:11:40 yes can I begin then just by dealing with your professional background appendix SiC see to your report sets out your background and experience relevant to matters in this inquiry I'm not going to rehearse all of that
00:11:52 I'm not going to rehearse all of that today but I just want to pick out some key points the first of those is that you have a PhD in neurophysiology from the University of Birmingham and you're also a diplomat member of the Royal College of pathologists is that right
00:12:04 College of pathologists is that right and then secondly for 17 years from 1974 to 1991 you were in the department of inhalation toxicology at the Huntingdon
00:12:15 inhalation toxicology at the Huntingdon Research Centre where you conducted and directed research in environmental and inhalation toxicology correct and that work included research into the effects of fire products on the nervous system
00:12:26 of fire products on the nervous system lung function and behavior in order to evaluate the mechanisms whereby fire products caused incapacitation and death yes in 1991 you joined the Building
00:12:38 yes in 1991 you joined the Building Research Establishment and up to 2006 you then continued to conduct and direct research on the toxicological and behavioral aspects of human fire exposures is that right
00:12:50 exposures is that right yes not include a lot of work on fire chemistry and fire testing so to develop that little your research included the psychology of human behavior and fires yes the chemical
00:13:03 behavior and fires yes the chemical yields of toxic products in fires yes and the evaluation of fire has a development you have also lectured on toxicology combustion chemistry and fire safety at a number of universities both
00:13:15 safety at a number of universities both national and international yes you've offered and presented a total of 152 publications and conference presentations is that right yes and you've been a nut member of a number of
00:13:27 you've been a nut member of a number of British and international safety committees relating to fire hazards fire toxicity fire safety engineering and means of escape you've also been a
00:13:38 means of escape you've also been a member of health expert committees established to give advice as the chief medical officer as a consultant you've advised on national and international standards and on toxic and environmental
00:13:50 standards and on toxic and environmental standards particularly involving things combustion and you've also advised on means of escape design in a number of building projects both in the UK and abroad as a legal expert you've been
00:14:03 abroad as a legal expert you've been instructed in cases both in this country and internationally as an expert in fire toxicity and human behavior and Fire yes and that included the Rose Park fire which you will be discussing today is it
00:14:18 which you will be discussing today is it right that in 2013 the institution of fire engineers awarded you the David rush Bosch medal for outstanding contribution to the advancement of knowledge in fire behavior and finally
00:14:30 knowledge in fire behavior and finally is it right also in 2015 that you made a commander of the British Empire for services to fire safety yes I've
00:14:41 services to fire safety yes I've explained before you came in professor that the first part of today's hearing is going to involve a presentation from you on your report it's in three parts the first part of which is headed
00:14:53 the first part of which is headed production of toxic smoke and gases and effects in generic domestic fire scenarios similar to those occurring at grenfell can I now invite you to give
00:15:05 grenfell can I now invite you to give the first
00:15:06 the first part of that presentation thank you very much
00:15:22 okay well then just to reprieve some of that I just wanted to highlight the fact that initially I'm going to be talking about generic effects and you might might be wondering why I'm going to address generic effects rather than just
00:15:34 address generic effects rather than just talking specifically about Grenville and I will come to that later and also to repress the point that my favorite one reported intend to be a general report does not make reference to specific
00:15:47 does not make reference to specific detailed evidence regarding individual Grenville occupants but buffets to write the report will be updated in an
00:15:58 the report will be updated in an expanding ballad as necessary in relation to the continuing evidence and I will be then bringing in a lot more detail about the witness from the witness statements and all evidence and
00:16:10 witness statements and all evidence and the transcripts of emergency calls made by Grenville occupants during the fire and I will also be reviewing the firefighter evidence I've already been doing a lot of work on this area and so
00:16:22 doing a lot of work on this area and so while I'm talking to you today although I'm not going to go into great deals about detail about individual persons a lot of this materials in the back of my mind as I speak to you as informing my presentations
00:16:33 presentations my main objective main purpose as I see it is to obtain detailed understanding of the conditions to which each person inside the tower is exposed and how
00:16:45 inside the tower is exposed and how their behavior escape capabilities and survival were affected now before I go bit further into my report I just wanted
00:16:57 bit further into my report I just wanted to highlight a few small points and the first one is what do we mean in the context in this context by toxicity or toxicology and I think he might find it
00:17:08 toxicology and I think he might find it useful to think of toxicology as having two aspects two main aspects one aspect is pathology which is basically tissue damage and the other is physiology which
00:17:20 damage and the other is physiology which is the directive immediate effects on people now pathological toxicological effects often take place over a long period of time they minimally they usually take days to develop
00:17:32 usually take days to develop unfrequently months two years but physiological effects which are also part of toxicology can happen in seconds two minutes and it's these physiological
00:17:43 minutes and it's these physiological effects of exposure to combustion products which is so important in determining whether people survive or die during a fire and it's really on
00:17:54 die during a fire and it's really on these physiological effects that I'm going to be concentrating my work to do and you'll be hearing a lot about this these these sort of compounds in smoke
00:18:05 these these sort of compounds in smoke that have physiological effects are mainly the irritants chemicals and the smoke particles themselves and certain gases and that brings me on to my second point but what do we mean by smoke well
00:18:18 point but what do we mean by smoke well smoke strictly speaking is the stuff that you can see during a fire the gray and black smoke and that is composed of very very fine respirable carbon
00:18:31 very very fine respirable carbon particles that's the essential part of smoke a tiny particles of soot essentially now in its purest form this material is relatively harmless apart from the fact that you can't see through
00:18:42 from the fact that you can't see through it but in reality during a fire the fire produces lots of other chemicals toxic chemicals and the main problem with these chemicals is they're highly
00:18:54 these chemicals is they're highly irritant and some of them are organic problem materials and some of them are acid gases and these compounds stick to these soot particles so that when the
00:19:05 these soot particles so that when the smoke gets in your eyes or you inhale it this can cause an immediate painful effect making it difficult to see and difficult to breathe so this is an immediate physiological effect of smoke
00:19:16 immediate physiological effect of smoke the smoke also contains permanent gases and some of these permanent gases are asphyxiant and you're going to hear me talking a lot today about asphyxiant what these gases do is that when you
00:19:29 what these gases do is that when you inhale them and you inhaled a certain dose of these gases they reduce the amount of oxygen getting to your heart and your brain essentially particularly the brain and the brain hypoxia that's
00:19:42 the brain and the brain hypoxia that's cause for this results in dizziness confusion
00:19:46 confusion and ultimately death influence so the effects of these is fixing gas is extremely important now when I talk about smoke in the next few slides are
00:19:57 about smoke in the next few slides are really encompassing all these things because they all move together through the together in the fire so what I'm talking about smoke I'm thinking about the smoke particles I'm thinking about
00:20:08 the smoke particles I'm thinking about the irritant compounds attached to those two car particles and I'm also thinking about the irritant gases and these fixing gases that are contained in that that's my okay so that's smooth now in
00:20:21 that's my okay so that's smooth now in order to understand what these are going to do to people how people are Grenville were affected and how it affected their ability to survive and escape you'll understand that I've got to take into
00:20:33 understand that I've got to take into account a lot of difficult different aspects of the way the fire developed and people were exposed at Grenville for example one thing I need to know is when
00:20:45 example one thing I need to know is when various different materials burned at different stages of the Grenville fire what toxic products did they produce and how much that's we talk there about the
00:20:56 how much that's we talk there about the yield of toxic products if I burn a kilogram of this lectin here how many kilograms of the toxic gas carbon monoxide will be released in theaters
00:21:07 monoxide will be released in theaters fear before Asante and so I need to know that and that isn't the main subject of the third presentation I'm hoping to give you today lying to you today well
00:21:18 give you today lying to you today well another thing that's obviously very important is not just what is formed but when it's formed and where it goes and so I really need to know how this smoke once formed either inside or outside the
00:21:30 once formed either inside or outside the tower has moved in and around the flats and the various spaces in the tower with time and I'm particularly concerned about when the smoke got into the lobbies at Grenville on different floors
00:21:42 lobbies at Grenville on different floors because this I feel was a key stage in the incident and so in order to do that I need a lot of very complicated information and I relying mainly for
00:21:54 information and I relying mainly for that
00:21:55 that the work of the other experts that you've heard from who have described and shown you images of the fire going up the outside of the tower and showing you the damage inside the tower and these other aspects so I need to make use of
00:22:08 other aspects so I need to make use of that but particularly I'm making use of what was observed by the occupants by the witnesses that you've been here during the course of the fire to help me build up a picture if you like of what
00:22:20 build up a picture if you like of what the conditions were and how they were developing with time and beyond that I also need to understand as we were hearing earlier about how individual
00:22:33 hearing earlier about how individual people will interact with this smoke once they're confronted by it and that in itself is another quite complex area because it's partly a physical or physiological thing but very much it's a
00:22:45 physiological thing but very much it's a behavioral thing if some one person sees a smoking the exit over here they may decide it's too dangerous to go through that smoke and they may stay here where another person may decide they can
00:22:56 another person may decide they can escape and they were plowing plow on through the smoke and so this brings me to my fourth point here which is that a lot of the evidence you're going to hear from me today is really essentially
00:23:08 from me today is really essentially qualitative in that unlike the evidence from the other witnesses where they can show you the actual picture of some part of the burnt Tower or something like that a lot of what I'm talking about
00:23:19 that a lot of what I'm talking about is going on hidden inside the tower at different times we don't know exactly when certain things were developed we don't know exactly the conditions and the timing under which all the materials
00:23:30 the timing under which all the materials burned and we certainly can't predict how each individual person would have reacted to what they were exposed to but by taking into account a lot of the work
00:23:41 by taking into account a lot of the work that I've done in previous years in the laboratory and also in for investigation and human behavior taken into the context of what we do know about Grenville and what the witnesses are
00:23:52 Grenville and what the witnesses are told us I hope by the end of the day you will agree with me that we start I'm starting to forget quite a good picture if you like of essentially what happened renfa so I hope that clarifies some of
00:24:06 renfa so I hope that clarifies some of these points so why is my phase one report based mainly on generic evidence on fire hazards rather than specifically on rental evidence well it's because we do have a lot more detailed information
00:24:18 do have a lot more detailed information from previous instance and investigations and unfortunately there are certain limitations as I've alluded to on the sort of evidence that we have from Grenville now I'm going to talk
00:24:29 from Grenville now I'm going to talk about bit more about this in a minute and thirdly and very importantly as we've heard a lot of my work is preliminary it's quite complex a lot of the information is just coming in or
00:24:40 the information is just coming in or hasn't yet come in and so because some of these detailed aspects are still under investigation it's better not to go into too much detail the amount of our individual pockets so as you've
00:24:54 our individual pockets so as you've heard my presentation is in three parts and we're going to start with the first one which is a very general about past work and not loads allude to excuse me
00:25:05 work and not loads allude to excuse me sorts of scenarios whether may have occurred at Grenville part two is more specifically to ceiling dealing with what happened to Grenville of part three is about the performance of the materials now one thing that I always
00:25:18 materials now one thing that I always have at the back of my mind in these cases and I'd like you to do the same is that what happens in far is very very time dependent and this is reflected in
00:25:30 time dependent and this is reflected in the performance-based design principle which underlines a lot of the fire safety engineering standards in fact I'm currently working on the British stand at the moment just being advised and
00:25:41 at the moment just being advised and leading a panel on this and so fire hazards depend essentially on two parallel processes there's two things going on simultaneously in fires and one
00:25:52 going on simultaneously in fires and one of these is the time from ignition when the fire starts to when that fire becomes dangerous so the fire starts very small and it gets bigger and bigger and it spreads throughout the building
00:26:03 and it spreads throughout the building and this is happening over a period of time the threat is increasing in parallel with that you've got the behavior of the occupants when will they first realize or be
00:26:14 when will they first realize or be warned there's a when will they decide to evacuate how long will it take them to evacuate and how does that parallel with the the threat hazard that's facing them
00:26:26 threat hazard that's facing them essentially in a design context what we want to ensure is that the available safe escape time the time available for escape is greater than the time people
00:26:37 escape is greater than the time people need to escape by an appropriate safety margin and I've kind of Illustrated that in principle down the bottom corner here so normally the work I do I'm concerned
00:26:50 so normally the work I do I'm concerned with actually trying to get people to evacuate very quickly in a fire situation and so one's very interested in the time from detection to the fire alarm and the time from the fire alarm to when people start to move and
00:27:02 to when people start to move and generally speaking if people start to be alerted and warned early on and they start to move early on there's usually a sort of golden early period during any fire when people can make a safe escape
00:27:15 fire when people can make a safe escape the problem with fires as illustrated by this curve here is that they tend to the rate of which they get worse tends to get exponentially greater so that if you
00:27:26 get exponentially greater so that if you delay then you'd get caught by this time period when the conditions can vary very rapidly deteriorate and a stark example that was the Bradford stadium fire and I
00:27:38 that was the Bradford stadium fire and I had some involvement the investigation off in 1985 on television match was being televised and it you can probably find the video on on the web if you want
00:27:50 find the video on on the web if you want to look for it but the point here it was but in the early stages here the fire was burning underneath the stand and you see people here standing around not too concerned initially but very rapidly
00:28:02 concerned initially but very rapidly then the fire went to flashover and sadly people running onto the pitch and their heat from the fire was igniting their hair so conditions can deteriorate very rapidly once things start to
00:28:15 very rapidly once things start to develop now in order to try to understand the hazards in a specific fire
00:28:23 fire and when it becomes dangerous ideally what I need is to determine the time concentration curves for the fire has its occupants were exposed to because
00:28:36 its occupants were exposed to because I'm trying to work out how long this time available is for escape and the three things that I'm the three hazards that are mainly concerned about are the smoke the visibility and density of the
00:28:48 smoke the visibility and density of the smoke because of the way that affects people's ability and behavior to escape I'm interested secondly in the asphyxiant gases because when people are inhaled a certain doses are so they like
00:29:00 inhaled a certain doses are so they like them to collapse and of course I'm also interested in whether they will be exposed to heat and suffer burns during the fire which in self-made incapacitate
00:29:11 the fire which in self-made incapacitate or kill and what I'm trying to do is determine the time during the fire when at which escape capability was affected by each hazard because they tend to
00:29:22 by each hazard because they tend to occur in sequence and when collapse and death occurred or is predicted to find out the effects on occupants escape behavior and survival now on the right
00:29:34 behavior and survival now on the right hand side here I have a set of curves from a reconstruction test of the Rose Park care home fire and I'm going to show you more of these in the next few slides but the only point I'm trying to
00:29:46 slides but the only point I'm trying to make at the moment is because we did a reconstruction of this fire we have the actual time concentration curves and measured for the heat the smoke and each of the toxic gases in the floor and
00:29:58 of the toxic gases in the floor and you'll notice here that at the beginning of this particular fire there's a period of about four or five minutes when conditioned there's hardly any smoke or gases in the in the experimental wreak
00:30:11 gases in the in the experimental wreak and during that time if a person was standing in that under those conditions in that room they would have four or five minutes of easy time for escape but after that the fire suddenly becomes
00:30:22 after that the fire suddenly becomes very serious and they would be in a lot of trouble and that's why in any fire hazard assessment situation I'm interested in how these different houses develop with I'm doing fine now in order to do a
00:30:38 I'm doing fine now in order to do a detailed analysis of the houses in the fire ideally when aren't investigating an incident there are a number of things that one needs to have the first thing
00:30:50 that one needs to have the first thing is a detailed far instant investigation and this is in order to obtain in-depth information on the interactions between what's happening to the building how the
00:31:01 what's happening to the building how the fire is developing and the effects on the occupants and this would involve the sort of things that have been done for Grenville examining the remains in the building its interviewed with survivors
00:31:13 building its interviewed with survivors and finding their detailed experience it's all that kind of basic fire investigation work you've been hearing about from the other experts it would also involve toxicology and pathology studies and this applies both to people
00:31:26 studies and this applies both to people who have died in the fire may have died in the fire also to people who have been survived the fire but had to go to hospital because they'd been injured and so in these studies what we want to know is to
00:31:38 these studies what we want to know is to what extent were people burned that's pretty obvious how much smoke did they inhale and you you can look at there's such in the airways and things like this both of living and dead people and
00:31:49 both of living and dead people and particularly there's one very important and powerful tool that we have it I'm going to be talking about quite a lot today and that on this slide is labeled C o HB c o HB stands for this for
00:32:03 C o HB c o HB stands for this for carboxyhemoglobin basically what happens in a fire is that there's always a certain amount of a toxic gas called carbon monoxide and as a person inhales
00:32:15 carbon monoxide and as a person inhales carbon monoxide the carbon monoxide combines with the hemoglobin in the blood to form carboxyhemoglobin and the longer the person is exposed to that
00:32:26 longer the person is exposed to that carbon monoxide and the higher the concentration of the carbon monoxide inhaled the greater the level of carboxyhemoglobin reached in the blood and so this is a very important tool in
00:32:39 and so this is a very important tool in assessing the extent and degree to which people have been exposed to toxic smoke because not only the co but all the other toxic gases in the fire are all together so the co HB is a very good
00:32:50 together so the co HB is a very good measure of this and it's routinely measured in both fire victims and survivors and so by looking at the carboxy hemoglobin in the blood of decedent's or fatalities or survivors
00:33:02 decedent's or fatalities or survivors tell us a lot about what they experienced in the fire now these four investigations can give us a lot of useful information but one thing they lack and this is particularly true for Grenville is there's no detailed
00:33:14 Grenville is there's no detailed information on the conditions during the fire from just from a investigation after the event and no detailed information on the effects of the individual hazards unfortunately we
00:33:25 individual hazards unfortunately we don't have any devices in Grenville which measure carbon monoxide as the father goes on we do have however the fatalities which in a way is a kind it
00:33:36 fatalities which in a way is a kind it is a kind of measure okay so that's the first part but then the next thing that we would like to do if we're doing an in-depth investigation is to set up a full-scale fire reconstruction test to
00:33:50 full-scale fire reconstruction test to duplicate what happened during the actual incident as far as we are able to do so well if we do such a test then we can as it rose read for Rose Park as it
00:34:03 can as it rose read for Rose Park as it shows on the right there then we can measure those gases the temperature in the heat with Sun and have a complete record of that but even this is not perfect because the test conditions in
00:34:17 perfect because the test conditions in an experimental duplication if your replication fire are not always identical no matter how careful you are to those that occurred during the actual incident and of course
00:34:29 during the actual incident and of course it doesn't tell us anything about the actual effects on the occupants all we're measuring is gases and smoke and I would like to take this point to emphasize because it's important later on that even if you set up a large-scale
00:34:43 on that even if you set up a large-scale fire test and repeat it several times with the identical setup all the fuels and the way you ignite it fires can be inherently variable and so
00:34:55 fires can be inherently variable and so that fire test can develop in several different ways in different circumstances even though you've done your ultimate best to try and duplicate the individuals so having a combination
00:35:07 the individuals so having a combination of instant investigation showing the damage and a test does provide useful information but it's not the end everything the third thing that we can
00:35:19 everything the third thing that we can do or I can do is to look at the human physiological data on exposures to individual fire gases and mixtures and so what I do is I use some physiological
00:35:31 so what I do is I use some physiological calculation methods most of which I've developed personally - and they're called Fe D models I'm going to explain a bit more about it in a minute but their main purpose is to predict the
00:35:43 but their main purpose is to predict the timing and effects of what would happen to somebody if they were exposed to the smoke irritants and fixiak gases or heat and heat in the conditions during the
00:35:55 and heat in the conditions during the experimental test fire so we don't have people there but I'm saying if we did have a person in there I can calculate what would happen to them now like any any model or any method there are certain variations and uncertainties
00:36:07 certain variations and uncertainties about this but it gives us a good way or predicting what would happen we do need to validate it against real human exposures in actual for instance now where these these methods become quite
00:36:20 where these these methods become quite powerful is when we combine all three and just to give you an example of this supposing I carry out a reconstruction test such as a growth part and I measure
00:36:33 test such as a growth part and I measure the carbon monoxide during the test well I'm able to calculate the as part of my analysis the amount of carbon monoxide taken up by a person who might
00:36:45 monoxide taken up by a person who might have been standing in that rig and calculate their carboxyhemoglobin say at the time they arrest you so let's say may be rescued they may have 40% carboxyhemoglobin in their blood what I
00:36:58 carboxyhemoglobin in their blood what I can then do is look at the blood samples taken from the actual items in the real incident and see if they have similar levels of carboxyhemoglobin in their blood to
00:37:09 carboxyhemoglobin in their blood to those I predict from the reconstruction test and if we find that the two measures are in reasonable agreement this provides validation that the
00:37:20 this provides validation that the conditions in the in the fire reconstruction test were a good recreation of the conditions in the actual instant and it also gives us a lot of entry information on how and when
00:37:31 lot of entry information on how and when the occupants were exposed and overcome in the fire so the purpose then is to understand how flames and smoke develop and spread through a building how and when occupants were exposed to
00:37:42 how and when occupants were exposed to heat and toxic smoke why they were unable to escape and how they died now try to apply that to grain fault one way
00:37:53 try to apply that to grain fault one way of looking at it is that grand fall can be considered as approximately a hundred separate domestic fires fires in what we call domestic dwellings ie fires in
00:38:04 call domestic dwellings ie fires in flats with and and looking at the totality there are four main kind of what I'm going to call occupant exposure scenarios so the first one for example
00:38:17 scenarios so the first one for example would be where occupants are alerted early during the fire and then they evacuate or perhaps decide to remain but the point is that it because they've
00:38:28 the point is that it because they've decided to move us or take action early they experience no or minimal exposure to toxic smoke or heat they may have some exposure which may influence their
00:38:39 some exposure which may influence their behavior but physiologically they're going to be minimally affected that's one scenario and that applies to in fact a lot of people who were in the Granville town secondly they may be in a
00:38:52 Granville town secondly they may be in a smoke-free flat for a while but then open the door to the lobby and find the lobby filled with a very dense smoke a very difficult situation because of the
00:39:03 very difficult situation because of the decision they then faced with and so then depending on the conditions in that smoke and the irritants and gases in that smoke they may then decide to
00:39:14 that smoke they may then decide to remain shut the door remain in the flat which has certain consequences or they may attempt to move through the smoke which may or may not have other consequences regarding whether they succeed in escaping or they
00:39:28 whether they succeed in escaping or they may be in their flats for an hour or more while smoke slowly builds up in the flat
00:39:35 flat perhaps leaking under the flat entrance door from the lobby and so they have a long slow gradually increasing exposure to these toxic smoke and gases rather
00:39:46 to these toxic smoke and gases rather than a sudden cliff edge high concentration and then you may have another situation where at some point four appears outside the flat and breaks
00:39:57 four appears outside the flat and breaks in and you've got a rapidly growing flaming fire in your flat and you've there not to deal with the consequences of this rapid short-term evacuation so
00:40:08 of this rapid short-term evacuation so those are the kinds of basic exposure scenarios if you like that term I'm considering here the other thing of course is there are a number of different fire development scenarios in
00:40:20 different fire development scenarios in different flats and other locations this refers to the way the fire actually developed which I'm going to talk about with it so I want to talk about Rose Park for two reasons one is as an
00:40:33 Park for two reasons one is as an example if you like of a fairly ideal fire investigation with a lot of information so as to show how these techniques can be applied but secondly because I believe quite a lot of the
00:40:44 because I believe quite a lot of the exposure scenarios occurring at Rose Park are relevant to the sorts of general exposure scenarios faced by at least most of the Grenville occupants so
00:40:59 least most of the Grenville occupants so this fire occurred in January 2004 and resulted in 14 deaths of the elderly residents of his care home and on behalf of the Scottish office and the Procurator Fiscal legal authority in
00:41:11 Procurator Fiscal legal authority in Scotland the Building Research Establishment our colleagues and I were asked to carry out a full-scale reconstruction of the actual incident my part in this was to to advise on the
00:41:24 part in this was to to advise on the setup of the rig and to assist with the measurement of station of the gas gases and the FE D calculations not only that but in fact
00:41:36 calculations not only that but in fact we were then asked to carry out another full care of reconstruction but this time with sprinklers what would have happened if there have been sprinklers in that care which we did and in fact
00:41:47 in that care which we did and in fact that has resulted in some changes in the legislation in Scotland regarding qualms for sprinklers and then thirdly we did another reconstruction where we replaced the ordinary doors on each of the
00:42:00 the ordinary doors on each of the residence rooms which were involved in the fire with half our fire doors but to see what influence that would have had on the way the hazard and might have developed and of course that's quite
00:42:12 developed and of course that's quite rather than to some of the issues that granny for then finding after that this is about the time I retired from BRE I was asked by the procreative fiscal to
00:42:23 was asked by the procreative fiscal to investigate the timeline and facts on the decedent's on the fatalities and survivors to understand the houses they were exposed to and how they were affected now this is a picture of the
00:42:36 affected now this is a picture of the photographs of the rig that we built to replicate the Rose Park fire you don't need to understand the details of this except to realize that basically what we
00:42:47 except to realize that basically what we had here was a sort of dogleg to corridors and off these corridors were the individual rooms were the occupants were spending the night but the point I want to make you is that in this rig we
00:43:02 want to make you is that in this rig we have tried as far as we can to exactly replicate the original building not just the building itself in the room the bedrooms but all the original materials
00:43:14 bedrooms but all the original materials were we with the aid of the Glasgow police we were able to source the actual materials identical to those that were there on the type night of the fire for example and that included with some
00:43:26 example and that included with some difficulty getting hold of these sort of reclining chair objects which were heavily padded and may well have been were a major source of cyanide
00:43:38 were a major source of cyanide the course of this farm now the second set of photographs here shows to you the rig after the test and you can see there's quite a bit of fire damage there the fire was actually in a cupboard on
00:43:49 the fire was actually in a cupboard on the left here started in the cupboard but another point I want to make to you is that although there's quite a bit of damage here this fire was a very short violent fire itself extinguished in a
00:44:01 violent fire itself extinguished in a few minutes because it was in an enclosed space so most of the building and the contents and everything else although damaged was still there for us
00:44:12 although damaged was still there for us to investigate and this contrasts to some extent with a lot of the material of Granville because Granville continued for about 24 hours a lot of the material a lot of material that was involved and
00:44:24 a lot of material that was involved and in a crucial earlier pier to the fire has been destroyed whereas a Rose Park most of it was still there so I'm just going to talk you through a little bit about the Rose Park incident so as I say
00:44:38 about the Rose Park incident so as I say it started as a short violent fire in a corner cupboard which is shown on the bottom slide here and again we tried as far as we could to replicate what was in
00:44:50 far as we could to replicate what was in that cupboard and this little graph here shows the temperature in the cupboard as the fire developed and you can see that it was very short-lived but it went up
00:45:01 it was very short-lived but it went up to about a thousand degrees centigrade at its peak very very violent short hot fire and the other thing that's important in this case we look at this
00:45:12 important in this case we look at this diagram on the right this is a plan of the building and the bit that we've replicated re where the fire was is this dogleg corridor here on all the rooms off it and there are two corridors
00:45:24 off it and there are two corridors essentially there's a corridor for set and as a corridor 3 in between the two is a set of fire doors and these fire doors closed automatically when the fire started triggered by the tection of the
00:45:35 started triggered by the tection of the system and this meant that the these corridor and the rooms of it were to some extent protector from the smoke during the fire but a particular feature of this incident was that this cupboard
00:45:47 of this incident was that this cupboard contain a lot of air assault and these aerosol cans exploded at intervals during the fire each time one of these cans exploded it caused a pressure and overpressure in
00:45:58 it caused a pressure and overpressure in this enclosed system and blew this door open allowing smoke to flow into corridor three and the rooms of corridor three and so what we've ended up with is a whole range of different exposure
00:46:11 a whole range of different exposure scenarios because the people who are shown in black here who are in open bedrooms off the Far corridor with their doors open and the night were exposed to
00:46:22 doors open and the night were exposed to the full force of all the smoke and gases produced by this short form and fire but the two people in these rooms here had their doors closed and so instead of having a short violent
00:46:33 instead of having a short violent exposure they had a long slow exposure as the fire as the Polish gradually builds up in their in their rooms a bit like happened in some of the Grand Tour
00:46:44 like happened in some of the Grand Tour flats when smoke was leaking in from from the lobbies and then we have the set of people of corridor 3 who had a somewhat lesser exposure still so we've got a sort of different sets that we
00:46:56 got a sort of different sets that we can't we can look at that and what I was able to do of course with this data as I say is we measured the gases and then I analyzed the effect and the next slide
00:47:07 analyzed the effect and the next slide is that have blown up simply simple diagram of this thing so basically as a result of this fire we had very high concentrations of asphyxiated gases in
00:47:18 concentrations of asphyxiated gases in the Far corridor 13,000 ppm of carbon monoxide and about 800 ppm of excuse me
00:47:29 monoxide and about 800 ppm of excuse me cyanide and that would and it was very hot in the corridor so anybody standing in the corridor would have been in very and during that period it would have collapsed and died within a few minutes and possibly
00:47:40 within a few minutes and possibly suffered some burns but there was nobody in the corridor but then we have the people who are in the rooms off the corridor who essentially got the same gas exposure but crucially not the same
00:47:53 gas exposure but crucially not the same heat exposure and this is something I want to develop in regard to Grenville talk a bit more in the municipality and then we have the people off corridor 3 and soothed me basically there are
00:48:08 and soothed me basically there are various levels of exposure so these two people here in closed rooms had a slow build-up over a period of about an hour before they could be rescued by the fire service these two people here where the
00:48:21 service these two people here where the red is shown had their doors open but they had some protection from the fire doors so their exposure was somewhat similar to the two blue ones if you like so those four people were alive was
00:48:35 so those four people were alive was survived for nearly an hour in the fire but but half an hour before these two were rescued and they were rescued alive two of them were comatose and never
00:48:46 two of them were comatose and never recovered consciousness in other words they had hypoxic brain damage from the carbon dioxide and cyanide they and two of them recovered consciousness and we're actually relatively well for short
00:48:58 we're actually relatively well for short prayer one lady was semi-conscious and she recovered in the ambulance and was talking to the ambulance service on the way to hospital when they got to hospital blood samples were taken and
00:49:09 hospital blood samples were taken and they were treated but sadly all fall of them later died and they died after 36 to 48 hours from bronchopneumonia so that to some extent this may have been brought on by the irritant smoke
00:49:21 brought on by the irritant smoke they'd inhaled on the other hand elderly people going to bed rest in hospital are very prone to developing bronchopneumonia particularly if they've
00:49:32 bronchopneumonia particularly if they've had a smoke exposure so they had a lesser exposure than the ones in the open bedrooms who I predict died within a few minutes and then the three pink people here had a lower exposure still
00:49:45 people here had a lower exposure still one person was just unconscious but recovered quickly the other two were conscious when they were rescued and they all survived the fire I made a good recovery
00:49:55 recovery and finally the lady in this room here had her door shut throughout he had two layers of protection and she was unaffected and in fact she was sort of joking with the fire officers as they helped her out of her room so you can
00:50:07 helped her out of her room so you can see a sort of spectrum of different types of exposure and of different effects all at which I think are relevant to grandfather because somebody who is in a flat in
00:50:18 because somebody who is in a flat in Grenville when the fire breaks in from the outside through the windows if they're standing in the same room as the fires broken in could be exposed to
00:50:29 fires broken in could be exposed to these rapidly deteriorating conditions with a sudden high peak of both heat and toxic gases similar to the sort of conditions faced somebody standing in that corridor if they had been there if
00:50:42 that corridor if they had been there if however somebody in a Grenville flat were to retire to another room and take refuge in another room within their flat after fires broken in so suppose suppose
00:50:54 after fires broken in so suppose suppose for example the fires broken in through the lounge window they may won't go and take refuge in a bedroom and this did happen a grain fault but let's say in this case they they left the interior
00:51:06 this case they they left the interior doors in their flat open throughout then they're going to be in a similar exposure scenario to the people in the open bedrooms of this Rose Park incident
00:51:20 whereas those who are in the closed rooms are relevant to people who also in a Grenville flat who may have shut the internal doors to take refuge maybe some
00:51:32 internal doors to take refuge maybe some people took refuge for example in a bathroom or in the hallway while there may be a fire the other side of their interior door burning in another room within the flat now in order to assess
00:51:46 within the flat now in order to assess these effects are just a little bit of technical stuff here each toxic gas in a fire at any time will use the concept of fractional effective concentration fec
00:51:57 fractional effective concentration fec and fractional effective dose f e d fe c is used for those hazards for which the immediate concentration is important
00:52:08 immediate concentration is important which is the smoke density whether you can see through the smoke and the irritant gases and smoke because these affect you immediately if they're there it affects you if the smoke clears your alrighty so immediate concentration
00:52:19 alrighty so immediate concentration allows you defect fe d to those hazards for which a certain dose level has to be acquired over a period of time before a certain effect is occurs there's more technical
00:52:32 is occurs there's more technical explanation of all this in my report but in order to follow the slides I'm going to show you the only thing you need to know is that on any of the charts I show you when the line for any hazard the FE
00:52:45 you when the line for any hazard the FE C or Fe D line for any hazard crosses one on the left-hand axis of a graph the y axis for growth then vanish projecting the time during that fire when a certain
00:52:57 the time during that fire when a certain hazard endpoint is reached where the hazardous reached a level where it would have some significant impairment of the ability of a person to escape or possibly whether they would collapse or
00:53:09 possibly whether they would collapse or even whether they would die at that point so here's an example which is from the grant for the circuits and grab from the Rose Park fire and this shows the
00:53:20 the Rose Park fire and this shows the over a short time scaling of ten minutes the concentrations of smoke and toxic gases fixie ant gases in the open bedroom of that fire corridor at bed
00:53:32 bedroom of that fire corridor at bed height because all the elderly people in the rooms were asleep at the time of the fire in bed and the lower picture is my
00:53:44 fire in bed and the lower picture is my fraction effective analysis of the effects that though the exposure would have on a person who was in that room on that bed and so what you can see here is
00:53:58 that bed and so what you can see here is that the Green Line is the smoke so there's a lot of smoke flowing in the the red line is the carbon dioxide which is always produced in the fires and the
00:54:10 is always produced in the fires and the black line is the carbon monoxide which is I told you earlier went to very high concentrations very quickly also crucially although it looks like a small blip here there's in toxicity terms
00:54:22 blip here there's in toxicity terms there's a high concentration of hydrogen son
00:54:24 son another asphyxiant gas then the lower image shows my calculated predictions of what exposed to that environment would a person exposed and what this shows is
00:54:37 a person exposed and what this shows is that round about four minutes this is the smoke line and it's going to get very densely smoke in there and this is crossing the line of one so about four minutes a person in that room have they
00:54:48 minutes a person in that room have they been able to get up underneath would have had some difficulty in moving through the smoke now in the actually stand all these elderly people were more or less confined to bed so none of them tried to move but crucially after six
00:55:03 tried to move but crucially after six minutes I'm predicting that a person exposed to this cocktail of asphyxiant gases would become unconscious and I've
00:55:15 gases would become unconscious and I've also calculating the uptake of carbon monoxide and that's predicted to reach a lethal level fifty percent at seven point nine minutes
00:55:26 point nine minutes another thing I've done in my calculation is to take the cyanide away and calculate how long it would be before somebody became incapacitated if there was no cyanide in this fire and
00:55:38 there was no cyanide in this fire and what the analysis shows is that if you didn't have the cyanide you'd have about an extra minute available to make your escape now a minute might not sound very
00:55:49 escape now a minute might not sound very much but in in a minute you can move 60 meters and possibly escape my building and this is why I feel in fires like this particularly far as involving upholstered furniture and
00:56:00 as involving upholstered furniture and things like domestic fliers cyanide can be an important factor in limiting the time available for people to escape it's a cause of incapacitation not so much a
00:56:12 a cause of incapacitation not so much a cause of death but a cause of why people who try to escape may collapse but the other term I've got in here is the effects of heat because we measure the
00:56:23 effects of heat because we measure the temperature in the bedroom I told you it was very hot in the corridor and what's crucially important here this is very very
00:56:32 very relevant to Greenfield is that this is the FE D curve for heat for somebody in that bit open bedroom and you see that this curve is rising quite slowly and it never gets to one on this axis which
00:56:45 never gets to one on this axis which means that during this fire is predicted that a person in that bed although they would receive rapidly lethal exposure to asphyxiant gases they would never suffer
00:56:57 asphyxiant gases they would never suffer from pain sees that this were plane from he this analysis they would never suffer pain from heat and they were certainly not suffer from burns and that was corroborated by the pathology on these
00:57:10 corroborated by the pathology on these victims because the bodies weren't burned and they all had very high carboxyhemoglobin as the test is predicting now this shows this slide
00:57:24 predicting now this shows this slide shows the pathology data the toxicology data from the actual victims and what I want to draw your attention to is the red numbers here which are the carboxy
00:57:36 red numbers here which are the carboxy hemoglobin in the blood of all the fatalities who are in the open bedrooms but I've said died after about seven minutes during this fire and you can see that they're all very high now if you're
00:57:48 that they're all very high now if you're you may remember I told you that 50% carboxyhemoglobin is a lethal dose most people world collapse and become unconscious at about 30% carboxyhemoglobin 50% is a lethal dose
00:58:02 carboxyhemoglobin 50% is a lethal dose so if 50% is lethal how how come when most of these people are above 50 but we can see levels of 80 higher levels here the reason for that is that once you
00:58:14 the reason for that is that once you become comatose and unconscious due to exposure to carbon monoxide you are not dead you may have collapsed but you're still inhaling the carbon monoxide have still quietly breathing and so as long
00:58:26 still quietly breathing and so as long as you remain alive you continue to inhale the 16 gases and your carboxyhemoglobin continues to increase in your blood until the point where your heart stops beating and you stop
00:58:39 heart stops beating and you stop breathing at that point the carboxyhemoglobin may come effectively frozen in the blood of that person and is very stable so it's a very powerful tool when the autopsies done maybe weeks later those levels of carbon
00:58:52 maybe weeks later those levels of carbon monoxide in the blood will be essentially the same so they tell us the dose received during me fired now the pink numbers here for those four people who were rescued a lie within a serious
00:59:04 who were rescued a lie within a serious condition and you'll notice two things one is that they're somewhat lower than that for the fatalities these were required over a long exposure period of up to an hour and giving two numbers
00:59:17 up to an hour and giving two numbers there for each one the reason for that is that these four these the blood samples are measured in survivors when they get to hospital and on the way to hospital they're given oxygen which and
00:59:30 hospital they're given oxygen which and this happened at Grenville to some people which is which what she's the carbon monoxide after the blood and people can often make a good recovery when that happens but I can compensate
00:59:41 when that happens but I can compensate for that and I can back calculate from them from the measurement in hospital to what the dose would have been at the time of rescue but in order to do that I need to know precisely when the blood
00:59:54 need to know precisely when the blood sample was taken after arrival at hospital and what happened in this case was that although I had all the hospital records I'm I had tremendous access to all the hospital records all the GP records of these people the in some of
01:00:08 records of these people the in some of these cases the time the blood sample was taken exact time wasn't recorded but I know approximately when it was recorded because of the procedures that were going on and the order in which these are carried out in hospital so
01:00:20 these are carried out in hospital so I've had to give a range because of that uncertainty and I suspect in reality these people were somewhere in the middle of that range so these are the people who have not quite had a lethal dose they survived for a while but then
01:00:33 dose they survived for a while but then died in hospital and then the blue lines there are for the people who they said were either on countries are awake and you can see they're lower still and so you've got this a range of effects so
01:00:47 you've got this a range of effects so where this takes us is that for Rose Park we have a detailed fire investigation we have an examination of the fire scene we have each child interviews with survivors and other witnesses so we do have some of that for Grenville but what we don't
01:00:59 that for Grenville but what we don't have for Grenville is a full-scale reconstruction fire tests of the parts of the building affected by the fire including the same materials and contents as in the actual incident we had replication at Rose Park of the
01:01:12 had replication at Rose Park of the original fire with measurement of the time concentration curves we had calculation of the incapacitating effects the FE D calculations we had all the data for carboxyhemoglobin both from
01:01:23 the data for carboxyhemoglobin both from the tests and from the actual fatality and so by comparing the two we were able to make a good analysis of the situation so when I compare that to what we have for Grenville we have some quite
01:01:37 for Grenville we have some quite important differences because for grandfa we have a very large and complex fire with differing development in individual flats so a full-scale rika duction would just not be feasible and
01:01:48 duction would just not be feasible and the Firebird for a very long period as I mentioned so the building and its contents were very different after the fire than they were during the early stages when most of the occupants were
01:02:00 stages when most of the occupants were exposed to heat possibly and particularly to toxic smoke and the combustible contents of many flats were completely burned out so we we can't say
01:02:12 completely burned out so we we can't say exactly when they burnt or what was there at the time similarly for the fatalities many of the bodies of people who were remains were recovered from the flats were were almost completely
01:02:23 flats were were almost completely consumed during this extended fire so it's difficult to establish the conditions they were exposed to during the fire before they died also the
01:02:35 the fire before they died also the pattern of fire development and smoke spread into and through the tower was very complex involving penetration into the flats of a proportion of combustion products from the exterior cladding and
01:02:47 products from the exterior cladding and insulation materials from the structural materials around the windows and then successive involvement of fires in the contents of different flats now so it is
01:02:58 contents of different flats now so it is possible however so what can we do for Grenville well it is possible as I've explained to identify a set of different exposure scenario for Grenville occupants similar to those
01:03:10 for Grenville occupants similar to those common in domestic fire incidents fires in houses and flats which happen in their hundreds every year now I've investigated many and for the some of
01:03:22 investigated many and for the some of these we do have a lot of detail of information which I think we can feel like translate into the Grenville's situation with regard to developing conditions and Rose Park is one example of such an investigation and from the
01:03:34 of such an investigation and from the information we do have on the development of the Grenville forints data from previous incidents and experimental fast I believe it is possible to estimate the likely effects and when full occupants also from
01:03:46 and when full occupants also from information on the fire performance smoke and toxic gas yields of generic versions of the exterior and interior structural materials at greenfield and
01:03:57 structural materials at greenfield and of typical house of flat contents such as furnishings and appliances the possible contributions for development and spread of toxic smoke into and
01:04:08 and spread of toxic smoke into and through the tower with time can be estimated but only very approximately so I've used these above sources to estimate the likely general effects on
01:04:19 estimate the likely general effects on rental occupants but we do have some very valuable data from the actual Grenville incident and in order to
01:04:30 Grenville incident and in order to validate these estimates for these generic effects for individual Grenville occupants I'm making a detailed examination of the witness statements and the all evidence and also that very
01:04:43 and the all evidence and also that very valuable are the transcripts of the emergency calls from the occupants during the incident and I have been asked questions about whether I've actually listened to these calls and
01:04:54 actually listened to these calls and part mainly because of time pressure so far I haven't done that but I certainly plan to do so as part of my face to work now I have to I'd like to really emphasize here that I'm finding these
01:05:07 emphasize here that I'm finding these witness accounts and transcripts extremely valuable and effective in understanding the experiences of occupants during the fire and the effects of exposure to toxic smoke both
01:05:19 effects of exposure to toxic smoke both for those who survived and for many of those who subsequently died during the fire so I would like to say to you that all of you all of those of you who have gone through this
01:05:31 of you who have gone through this traumatic experience and then given these detailed witness statements to the police and those of you who have given you all evidence in court be assured that we are taking I'm particular I'm
01:05:42 that we are taking I'm particular I'm taking great note and studying a great care all those all the things that you said very valuable also the witness descriptions of how smoke and flames
01:05:54 descriptions of how smoke and flames penetrated different flats the lobbies and stair are also providing me with a good understanding of these aspects which I'm using to validate my generic predictions of likely smoke development
01:06:05 predictions of likely smoke development spread and Composition also I mentioned the importance of carboxyhemoglobin well
01:06:17 the importance of carboxyhemoglobin well we do have some blood toxicology data for Grenville there their blood samples are available for actually there were 24 Tala teas but there was only 15 of those
01:06:30 Tala teas but there was only 15 of those for which the toxicologist was able to assign a numerical value for the carboxyhemoglobin in their blood now some of these people died in flats some
01:06:43 some of these people died in flats some in lobbies and some on the stair I've also viewed photographs of the remains of these fatalities currently awaiting the full autopsy reports which
01:06:54 awaiting the full autopsy reports which I will consider as part of the Phase two so this information taken together with the witness accounts and the emergency call transcripts considered in the context of data from previous incidents
01:07:06 context of data from previous incidents is providing me I feel with a good basis for assessment of causes of incapacitation and death for grenfell fatalities now I just want to briefly at
01:07:20 fatalities now I just want to briefly at this point before I go more deeply into some of this material address one very important issue which is were the grain for fertility is affected by exposure to
01:07:31 for fertility is affected by exposure to heat or burns for they died or were they overcome by toxic smoke now I stress that my work is
01:07:43 toxic smoke now I stress that my work is still preliminary but for my review of the grain for specific evidence so far and taken in light of data from previous instance it's a strong possibility that those who died did so from smoke
01:07:57 those who died did so from smoke inhalation rather than being burned and I'm placing particular emphasis here on the available carboxy hemoglobin data I'd also want to point out that while in
01:08:11 also want to point out that while in inhalation exposure to irritant smoke can be quite unpleasant and caused dis breathing difficulty and discomfort exposure to these asphyxia gases people
01:08:22 exposure to these asphyxia gases people are totally unaware that they're inhaling them they have no real effect until the point where you suddenly feel dizzy and collapse so dying from carbon dioxide even if the cyanide in the maker
01:08:33 dioxide even if the cyanide in the maker is not a painful death you basically faint and then go into it slowly a coma you die I think that a
01:08:44 slowly a coma you die I think that a good point to have a break yes yes all right well we do have a break roughly every hour we'll take one now okay I'm going to ask you please not to discuss their evidence with anyone once you
01:08:55 their evidence with anyone once you leave the room and we'll come we'll resume the course past 11:00 and you might give me a shirt that gives you just over 10 minutes that's right yes yes if you go the ostrich she'll look after you thank you good thank you very
01:09:06 after you thank you good thank you very much
01:09:19 right 11:15
01:21:30 right professor
01:21:36 all right you happy to carry on yes if we can get the just below I mean yes you will cut off of the range but um I may have ended the presentation we might get
01:21:47 have ended the presentation we might get someone to start it again right
01:22:13 we've got the experts on the job
01:22:21 Oh
01:22:24 thus possible no idea sorry
01:22:30 Oh
01:22:51 you're right can you pick it up from there
01:23:03 when we had that one
01:23:08 you know
01:23:14 Hospital yep right yeah okay no apart
01:23:25 Hospital yep right yeah okay no apart from the Rose Park study that I mentioned earlier something very useful work I think I was involved in quite a long time ago now was some full-scale
01:23:37 long time ago now was some full-scale reconstruction fires looking at typical domestic fire scenarios so when I was at PR II and in those days we had an
01:23:48 PR II and in those days we had an experimental house like a typical semi-detached house at the time you know in a big hangar in Coddington when Bedfordshire where we could do the experiments and we carried out a series of fires looking at the toxicity toxic
01:24:02 of fires looking at the toxicity toxic hazard from upholstered furniture so all these files involved setting fire to armchairs basically as shown in the bottom left there and we had them in a sort of flat rig like a with a room
01:24:13 sort of flat rig like a with a room corridor a bedroom we also have this two-story house where we did most of the tests and what I want to explore with
01:24:24 tests and what I want to explore with you is particularly here is the hazard faced by somebody who was upstairs during such a fire so what happened in these forests will reignite the furniture and this is also true for anybody who's in the room with the fire
01:24:36 anybody who's in the room with the fire downstairs when is that initially the conditions are reasonably 9 you could stand here in that room and watch this fire when it's that sort of size but if you can just make it up already a layer
01:24:48 you can just make it up already a layer of smoke is building up under the ceiling so any toxic products that are formed by this smoke and any heat is taken up the ceiling so if you were in the room down here you're not immediately exposed to them
01:25:00 you're not immediately exposed to them dr. Blay our smoke gradually fills down bit like an inverted bathtub filling with water until what in many of these fires we had the room to the hallway
01:25:11 fires we had the room to the hallway open in some we had it closed and when we have the room door open when the smoke gets below the level of the top of the doorway or the soffit the smoke flows out into the hall
01:25:22 flows out into the hall upstairs and mixers were there refills landing above and all open areas within the house because this is an enclosed system after ten minutes or so
01:25:34 system after ten minutes or so these fires self extinguished they went out because of they used not sufficient oxygen for the fire stopped burning but this left this house filled with a
01:25:45 this left this house filled with a highly toxic atmosphere evenly distributed throughout all the open spaces upstairs we had a closed bedroom which we measured conditions in and we also had an open bedroom and this is the
01:25:57 also had an open bedroom and this is the conditions in the landing here so you've got 5,500 ppm of the carbon monoxide you've got five percent carbon dioxide which stimulates breathing and increases the rate of uptake of other gases you
01:26:10 the rate of uptake of other gases you have some decrease in oxygen but not to worry but you also have a very high concentration of cyanide which is caused by burning the foam and the furniture and the covers in you also have here we
01:26:21 and the covers in you also have here we measured these irritant organic chemicals that sting your eyes and make it difficult to breathe and of course it's hot but as I told you before in brunette in relation to Rose Park
01:26:33 brunette in relation to Rose Park although it may be very hot in this room here but other time the smokers come and mixed and gone upstairs and the structure is absorb some of the heat the temperature actually on the landing here
01:26:44 temperature actually on the landing here is not too bad it's sixty degrees centigrade now you wouldn't want to spend all day 60 I mean it's well below the temperature of a sauna for example but he would be you'd sense that it was hot and what I would like to kind of
01:26:56 hot and what I would like to kind of explore with you is the how the Dynamo if you like all the conditions faced by somebody who might have been asleep in this bedroom here by the way these
01:27:09 this bedroom here by the way these photographs this is the top of the stairs looking down early in the fire and the right-hand side shows the view the camera view about five minutes later and you can see by that time you can't
01:27:23 and you can see by that time you can't see anything either in the room where the fire is or crucially upstairs on the land it's hand in front of your face you can't see the hand around your face which is something that would
01:27:35 which is something that would by many Grenville occupants when they try to step out of their front door into the lobby that grain field so what will this person do in this situation let's
01:27:46 this person do in this situation let's suppose they're asleep and the smoke alarm goes off so they go to this door is closed and they open it and what they face by their face by this dense smoke and a bit of it's going to come in and
01:27:59 and a bit of it's going to come in and they'll sting their eyes I'm very very unpleasant so obviously their first reaction is most like to be to shut the door and stay in the bedroom they will then either remain there maybe they'll call the fire service or they
01:28:11 they'll call the fire service or they may try it and bring a 2-story house they may attempt to escape through the window now I've come across many examples of this thing in real life and I've known people who have done exactly this but they've opened the door they
01:28:24 this but they've opened the door they found conditions very frightening and in one particular recent case I've worked on they actually got out and came down a drainpipe to escape three young people
01:28:35 drainpipe to escape three young people in another one which is quite interesting in this context I'm Ehren woke like this he started to go down the stairs and as he said as I tried to go down the stairs I felt that it was hot
01:28:46 down the stairs I felt that it was hot not painful but just you know something wrong and and of course it was very smoky and irritant and of course so he didn't know what was below it could be an arranging inferno for all he knew so
01:28:57 an arranging inferno for all he knew so he halfway down the stairs he turned around and went back took refuge in the bedroom and called the fire brigade from where he was rescued so in this case here with these gases if this person
01:29:09 here with these gases if this person stepped out now on to the landing what would happen to them well the first thing would be they can't see the second thing within seconds is they would be suffering from the irritants
01:29:20 suffering from the irritants which would affect their vision their breathing and be very unpleasant if they don't turn back at that point but continue at some point they're going to start taking some breaths and they will
01:29:32 start taking some breaths and they will be inhaling these very high concentrations of asphyxiant gases and in my example here they've gone a few steps and then because of that they've collapsed at the bottom of the stair now
01:29:44 collapsed at the bottom of the stair now as I said before they're still alive but they're breathing King debris these toxic gases if they're rescued at that point and treated with oxygen in the ambulance they may make a good recovery if they've had a more severe
01:29:55 recovery if they've had a more severe exposure I did my four cases at Rose Park then they may suffer permanent brain damage are common and from which they'd never recover they may be common
01:30:07 they'd never recover they may be common findings that people who've been poisoned by carbon monoxide even if they don't have obvious neurological symptoms they suffer from personality changes and/or they may be there so badly
01:30:21 and/or they may be there so badly effected they never recover consciousness alternatively they may have inhaled a dose of smoke sufficient and this is a fairly common occurrence but several hours about two to three a
01:30:34 but several hours about two to three a few hours three hours after the time of exposure they may go through a crisis where they get lung edema and inflammation so the irritant smoke
01:30:45 inflammation so the irritant smoke they've inhaled causes water to build up on the lung and that makes it very difficult to breathe and so they may actually die at that point or they may with treatment come through so these are
01:30:56 with treatment come through so these are the kind of hazards that people will face and on the next slide here I show the FE D analysis for this case of somebody stepping out onto that landing
01:31:07 somebody stepping out onto that landing and the first thing so we're looking for what any of these lines cross this one on this scale right down here and what this shows is that the concentration of irritant smoke is immediately about 15
01:31:20 irritant smoke is immediately about 15 times the concentration that would be predicted to give you difficulty in progressing through it and breathing it wouldn't kill you but it would make things difficult secondly because of the
01:31:35 things difficult secondly because of the new 16 gases here I'm predicting that the overall effect which are additive of these different gases would cause after a couple of breaths in that particular atmosphere the first is likely to collapse unconscious and when I remove
01:31:49 collapse unconscious and when I remove the cyanide they've got 150 seconds so you can see here in this case the presence or absence of cyanide couldn't make significant difference to when they're able to get down stairs now through the front door which
01:32:00 stairs now through the front door which will only take 10 20 seconds or so okay so that's that's that's an example of a sort of scenario or situation that wood
01:32:11 sort of scenario or situation that wood was placed by a lot of Grenfell occupants and there's as the two sides to this there's the behavioral side and the sort of physiological side so the behavioral side of it is I've got this
01:32:23 behavioral side of it is I've got this very difficult decision to make which was faced by rental occupants in some cases several times during the course of the fire early in the fire you open the door you see smoke maybe this was after
01:32:36 door you see smoke maybe this was after about 1:30 and the morning of the fire when there was a lot of smoke in those lobbies and you have to make this difficult decision do I stay put or do I decide to try and make it to the stair
01:32:47 decide to try and make it to the stair and go out if I stay if I if I go to the stair and get out that's that's over but if I decide to stay put I may then have to revisit this decision later on as conditions deteriorate outside the flood
01:32:59 conditions deteriorate outside the flood so so I think that example showed you some of the issues that people were facing and the consequences of doing one thing or the other I just want to briefly now just talk a little bit about
01:33:10 briefly now just talk a little bit about some of these different two hazards and the first one is smoke and this is this is some work that was done years ago by Professor Jin in Japan where he got volunteers to walk down a corridor while
01:33:23 volunteers to walk down a corridor while being exposed to smoke to see how their movements speed and ability to progress was effective and what Professor Jin found was that when he used non-irritant
01:33:34 found was that when he used non-irritant smoke which is this blue line here people with no smoke walked at about one to one point one meter per second that's typical walking speed but once the smoke density got such that you could only see
01:33:46 density got such that you could only see about two meters their behavior changed from walking as if they could see to walking as if they're feeling their way in darkness do you understand I'm feeling away along the walls and things like that and at that point their speed
01:33:58 like that and at that point their speed was greatly reduced at 0.3 meters a second but when he replaced the smoke with irritant smoke he found that the same phenomenon occurred at a at 5 meter after
01:34:09 after density the combination of optical and irritancy gave the same effect so it although theoretically you could see for four or five meters you still affected
01:34:20 four or five meters you still affected so that's the physical effect on progress but the other effect that's more important in some ways we're as important is the behavioral effect and summed up baby very in one line almost
01:34:31 summed up baby very in one line almost here but there are two big studies done one in actually at the BRE fire search station by dr. wood and one in America
01:34:42 station by dr. wood and one in America by Professor Brian at the University of Maryland where torero is connor factor arrow is now the brian professor at Marion and I've taught it there so so what those products people did was they
01:34:54 what those products people did was they measured they I might a lot of incidents and they were looking at this kind of decision-making up when do people just start to continue or what smoke conditions will they turn back and they
01:35:05 conditions will they turn back and they found simplifying it that once you get to about four metres visibility quite a large proportion of people will turn back rather than continue through the
01:35:16 back rather than continue through the smoke so they're just the density of the smoke and some extent it's irritancy because he's a real incidence is having a profound effect on their escape behavior and capability however I would
01:35:29 behavior and capability however I would point out that I believe that this effect and from the studies I've made it's very much depends on the context right so if you imagine somebody who's in for example a grandpa flat and the
01:35:43 in for example a grandpa flat and the flat fills with smoke this could be like a flat six column of flats in the flat six location on the tire during the early stages of the fire the fire comes in and the smoke comes in from outside
01:35:54 in and the smoke comes in from outside and fills your flaps no matter how dense that smoke is you're going to be very highly motivated to get to your front door and out into the lobby which at that time was relatively smoke-free so I
01:36:05 that time was relatively smoke-free so I would say whatever the density you will try and I've come across lots of instances where people have moved through very dense smoke as indeed they did at Brentford on the other hand if you're in a reasonably smoke-free flat and you open the door
01:36:18 smoke-free flat and you open the door and see dead smoking then you're much more likely to stay where you are on the door so it's good it depends on the context the other the other thing is I want to talk about is this fix use and again it's the
01:36:29 this fix use and again it's the difference between why there's a difference really between cyanide and carbon monoxide and in these experiments here subjects were exposed to carbon monoxide at different concentrations on
01:36:40 monoxide at different concentrations on the right hand axis here and what we're looking for is the dose which is roughly the concentration which they are exposed multiplied by the time at which until
01:36:52 multiplied by the time at which until they became unconscious and so you can see here at the top left hand there when they when they were exposed to a thousand parts per million then collapse occurred unconscious after twenty-six
01:37:03 occurred unconscious after twenty-six point six minutes if you multiply those two figures together you get 26,000 600 ppm minutes that's the sort of measure of dose when they were exposed at the
01:37:14 of dose when they were exposed at the bottom of that column to 800 ppm 8,000 sorry thank you then they collapsed after about three minutes and and the multiplying the two
01:37:25 minutes and and the multiplying the two together give you roughly the same number so there's a very clear relationship that over this time scales at least affects the co of purely dose related but this contrasts with the
01:37:37 related but this contrasts with the effect of cyanide here and I was cyanide when they're exposed to 87 parts per million then they were able to function for half an hour multiplying those two together gives you two thousand six
01:37:49 together gives you two thousand six hundred and ten but at 300 ppm they collapsed after point-9 of a minute very very quickly multiply those together you get 270 so what this tells us is that a
01:38:00 get 270 so what this tells us is that a long exposure to a low concentration which in this context is less than 100 parts per million of cyanide can be tolerated quite well if you exposed to twice that
01:38:12 if you exposed to twice that concentration so two to three hundred then you're going to collapse within a couple of minutes and that's partly why I believe cyanide causes incapacitation in fact not necessarily death but
01:38:24 in fact not necessarily death but incapacitation this slide is about carboxyhemoglobin in blood and this study on the left here was done by Professor Gordon Nelson United States and it's a study a very large forensic
01:38:37 and it's a study a very large forensic database of people who have died from carbon monoxide poisoning essentially either in fires or from CO poisoning itself so the green bars here are the
01:38:48 itself so the green bars here are the concentrations of carboxy hemoglobin in the blood of fatalities of people who have died from accidental carbon monoxide exposure whether from caused by
01:38:59 monoxide exposure whether from caused by 40 home heaters water boilers things like that or in this case it's quite an old database mostly young men committing suicide by explode themselves to exhaust fumes in the garage before before we had
01:39:11 fumes in the garage before before we had catalytic converters and what this shows is that there's quite a range of sensitivity in the population before people actually died but most of these people have got at least 40 to 50
01:39:22 people have got at least 40 to 50 percent or more the mode the most common most frequent dose at death is between 70 and 80 percent Kobach's of hemoglobin a few people survived until they've nearly a
01:39:34 people survived until they've nearly a hundred percent amazingly before they actually died now if you compare that to the red bars which are for people who've died in fires but not burned then you
01:39:46 died in fires but not burned then you can see that it follows roughly the same pattern and that gives us some confidence that the main cause of asphyxiant death in fires is in fact carbon monoxide that's the main agent
01:39:58 carbon monoxide that's the main agent causing death or it subsistent with that however there is a bit of a left shift here there are some people here and so this tells us that there's something else as well in fires that's
01:40:11 else as well in fires that's contributing although Co is the main thing there's something I've not may well be cyanide and some other things in fires now the right-hand curve is from a Polish researchers known as patch be
01:40:25 a Polish researchers known as patch be ACH and this is about survival as opposed to death so in this case these are people who have been rescued having had common oxide poisoning and the
01:40:36 had common oxide poisoning and the probability that with treatment they would survive and what this shows is that up to about 30% carboxyhemoglobin here everybody survives but then you see
01:40:47 here everybody survives but then you see the survival rate drops off very quickly and the 50 percent survival rate which is what dr. gore just look for is indeed at 50% carboxyhemoglobin
01:40:58 at 50% carboxyhemoglobin whereas very few people survive having had sixty to eighty percent and in the next slide I've compared Patty's data to
01:41:09 next slide I've compared Patty's data to the Rose Park data so here we have all the people who are dead in their rooms very quickly at Rose Park and you see they're all in this very high CHP group they've died from smoke poisoning as I
01:41:20 they've died from smoke poisoning as I pull up the reason I'm going into this in such detail is because of what we're going to see and they rose in the Grenville victims these are the four ladies who were rescued alive but then died in hospital there in the middle
01:41:32 died in hospital there in the middle almost at this 50% point and these are the ones that survived and we've got good agreement with the Polish data
01:41:40 this slide shows us from a London Fire Brigade database of the other burns and carboxyhemoglobin in fire eight artists
01:41:51 carboxyhemoglobin in fire eight artists in the London area I think it was from one particular year and I forget the exact year but the point about this is that we have not only a record of the extent of burns the white bars are burns
01:42:02 extent of burns the white bars are burns and the gray bars are serious possibly life-threatening blows the black is the number of cases with different levels of carboxyhemoglobin and importantly these
01:42:15 carboxyhemoglobin and importantly these two pictures one is for people who are not in the same room as the fire and this is for people who are in the same room in the fire and what you can see is that most people who have died in a room
01:42:28 that most people who have died in a room for example in a bedroom at Grenville when the father's alone all have very high carboxyhemoglobin level and they all know very little if any further so
01:42:39 all know very little if any further so these are people dying from smoke inhalation whereas in the room of fire origin there are quite a lot of people who have very low carboxy removing levels less than about 20 or so and a high incidence of
01:42:52 about 20 or so and a high incidence of burns so these are people who basically have died from burns before they had time to inhale a high dose of carbon monoxide and so if we find certain
01:43:05 monoxide and so if we find certain levels in in a in a body of a person who's died and that body then gets burned but we find these very high concentrations but breathe in most cases
01:43:17 concentrations but breathe in most cases that tells us that they died from carbon dioxide or smoke poisoning rather than from birds if they've got only ten or twenty percent then we suspect that it may have been heat and burns that killed
01:43:30 may have been heat and burns that killed them and so what I'm telling you is that all the Grateful cases are up here some very briefly this is the effect of how we calculate time to effect from heat
01:43:41 we calculate time to effect from heat they're two kinds of heat exposure in fires one is heat radiation which comes directly from the fire and from the hot upper layer when you have a hot smoke and the other is if you're in velop tin
01:43:55 and the other is if you're in velop tin smoking it's supposed to Hut air hot atmosphere then this is human data on time of Tolerance and there is one important point I want to draw to your attention for this curve which is that at 200 degrees centigrade
01:44:08 which is that at 200 degrees centigrade in in air it's possible for volunteers to tolerate that for several minutes before they start to feel pain to their exposed skin and this is some relevance
01:44:21 exposed skin and this is some relevance to Grenville because you may remember dr. Lane found that some of the light diffuses in stare believe it was between floors 12 and 16 around there and I went
01:44:34 floors 12 and 16 around there and I went saw these myself was softened by heat so she was look and she decided that the temperature in the stair may have been in this sort of region and I'm saying
01:44:45 in this sort of region and I'm saying that even if it was as hot as that virtually above head height weight been cooler as lower down people could still have got through that those few floors without necessarily suffering severely
01:44:57 without necessarily suffering severely although in reality I this may have occurred after those people moved I want to get a bit know about scenarios and we've talked about some obviously here
01:45:09 we've talked about some obviously here so because these are the closed and closed scenarios I've described one important point about these so I'm going to talk about a bit later is that whenever I first starts to burn in an
01:45:21 whenever I first starts to burn in an enclosed room initially if I set fire to this laptop here we'll have lots of nice fresh air from the room coming in to support the flaming combustion the result of that is that the combustion is
01:45:33 result of that is that the combustion is very efficient and so that January the products of combustion are carbon dioxide water and heat and anyway all that goes up to the ceiling so we're all safe for a while you'll be pleased to
01:45:45 safe for a while you'll be pleased to hear it forms a layer under the ceiling and it's some time before exposed to but if the room is enclosed this layer quickly fills down and once the flames are burning in their own smoke as it
01:45:57 are burning in their own smoke as it were in this oxygen depleted layer then the combustion process becomes very inefficient and products of inefficient combustion are a big increase in the
01:46:08 combustion are a big increase in the yields of carbon monoxide from any carbon in the fuel smoke itself that goes up and it was only knighted in the fuel you start to generate a lot of cop up hydrogen Sun and that's what's
01:46:21 up hydrogen Sun and that's what's happened in these furniture fires here
01:46:29 now briefly this has I will don't address this now distant passing this may have some relevance to the conditions in the when the PIR was
01:46:41 conditions in the when the PIR was burning on the outside of this town because the PIR insulation initially at least is encased in a cavity with the
01:46:54 least is encased in a cavity with the rainscreen cladding outside so it's in a sort of enclosed space like a big pipe when a fire occurs in that material at
01:47:06 when a fire occurs in that material at the bottom of the area where the flaming is it's exposed to quite good air conditions there's air coming up from below and there's the fuel being exposed the two combine to combust and those
01:47:19 the two combine to combust and those products then continue up due to buoyancy and those products then are now depleted in oxygen but the heat from the fire is likely to decompose the same
01:47:32 fire is likely to decompose the same material higher up the pipe and that material you could post higher up the pipe is now going to encounter those thermal decomposition products we call them are going to be encountering a hot
01:47:43 them are going to be encountering a hot plume which is depleted in oxygen and what is important in this context is the fuel-air ratio at various points so when there's an excess of air for combustion
01:47:54 there's an excess of air for combustion as in this case then combustion is inefficient but when there's more fuel and air as in this case or possibly may have occurred just for a period in some
01:48:07 have occurred just for a period in some of this clad insulation then you tend to get higher yields of toxic products the term that we use for this is the equivalence ratio which is the relation
01:48:20 equivalence ratio which is the relation to the fuel narration so when when the equivalent ratio is less than one that's efficient combustion low toxicity when this ratio is greater than one you can get highly toxic products going back to
01:48:32 get highly toxic products going back to these these Brunel files there there's another important aspect Google if our tests are described you so far were conducted in enclosed situations where the fire grew
01:48:44 enclosed situations where the fire grew then became under ventilate and then more or less went out now I Grenville that would be sort of equivalent to fire coming in around only a closed window on
01:48:57 coming in around only a closed window on the outside of brimful which was described by some people so you may have fire in your flat but at this point the windows are still intact that would be a sort of situation similar to these room
01:49:08 sort of situation similar to these room fires instead of the furniture burning its materials structural materials initially at least around the window area and may then spread to involve the content and that's going to remain a
01:49:22 content and that's going to remain a relatively small fire and it's going to become very toxic very poisonous very quickly but a very different situation occurs if the window is fully open or in
01:49:35 occurs if the window is fully open or in particular as it Grenville if the window glazing fails and the whole window falls out now when that happens you're in this kind of situation where you have
01:49:46 kind of situation where you have continuous air coming in through the bottom of the window to feed the fire the fire can then get bigger and hotter and it will continue to burn it can continue to burn until all the fuel in
01:49:57 continue to burn until all the fuel in building all the contents is burned away and consequence of this is that the fire the upper layer becomes very hot and the downward thermal radiation from hot
01:50:09 downward thermal radiation from hot upper layer once it gets about about 600 degrees centigrade it can ignite fuels remote from where the fire is started so you may have a fire initially burning near the windows and the hot plume is
01:50:22 near the windows and the hot plume is flowing towards the back of the flat once those temperatures get so high even those materials can ignite and there's a very clear example of his here from experiments that we carried out the BRE
01:50:34 experiments that we carried out the BRE many years ago
01:50:42 and this is the point of thrush over because this hot upper layer is radiating down and you can capture suit just igniting although some newspapers and various materials on this occasional
01:50:54 and various materials on this occasional table so that is the exact point at which flashover occurs now as you can see these these conditions are extreme and certainly nobody could survive for
01:51:05 and certainly nobody could survive for more than a few seconds in that room but one of the questions is what would happen to them in the rest of the flat would they be able to survive any longer if they took refuge and I think
01:51:16 if they took refuge and I think conditions like this would be difficult to survive for very for more than a few minutes even if you took refuge somewhere although it's got a complicated situation and there are many
01:51:27 complicated situation and there are many different variants we've observed in different flats grain field just to say that we have these different rigs I mentioned the flat rig and this is the
01:51:39 mentioned the flat rig and this is the open room where we studied these more developed fires I'm going to go bit quicker now just to I think I'll cover most of this so though this is illustrates the conditions in one of these furniture fires with time as it goes on so you can
01:51:52 fires with time as it goes on so you can see after five minutes you can't see anything if you're in that room but the amount of damage you can see here is quite small I've mentioned a number of times that in order to create lethal
01:52:05 times that in order to create lethal conditions in the volume enclosed volume of a flat or house you really only need to burn about five to seven kilograms of material which represents in this case
01:52:16 material which represents in this case about a third to a half of that that was enough to make those conditions in the in the house and this this slide shows
01:52:27 in the house and this this slide shows the conditions there's the landing again and this is the can't see anything after five minutes top right shows the FE D for the occupants of the open bedroom upstairs and the crucial difference here
01:52:39 upstairs and the crucial difference here is that although they were going to be overcome by the same excuse me same smoke very quickly
01:52:46 because the heat has gone as heat downstairs but it's been lost from this more sheltered place this slide compares the smoke in a situation where we've
01:52:57 the smoke in a situation where we've closed the lounge door and measured the smoke throughout the house and the exhaust an ordinary door not a fire and then we've measured the up with with to the left hand one is the in
01:53:09 with to the left hand one is the in closed fire the right hand one is one with the door open and it's a bit hard to understand here but basically this is the smoke density and these lines here are inside the closed room and you can
01:53:22 are inside the closed room and you can see they very rapidly go up at the top of the growth but the conditions in the hallway and landing other rooms are much less smoky and this demonstrated if you're in our ordinary two bedroom house
01:53:33 you're in our ordinary two bedroom house and you've taken the trouble to shut the lounge door before you go to bed if you have a fire in your lounge and you have a very good chance of getting faster to the front door if you shut the door but
01:53:45 the front door if you shut the door but if you look a door open then as you can see just a glance the hole in the house rapidly gets filled with dense toxic smoke this shows the condition in Rose
01:53:56 smoke this shows the condition in Rose Park for the saamne taking refuge in a closed bedroom closed room and exceed the contrast instead of home these rapidly increasing concentrations you've got a very very slow gradual filling up
01:54:08 got a very very slow gradual filling up a reprieve an hour or so and uptake of carboxyhemoglobin by the occupants so this shows how somebody who's taken refuge in a flat for example it grandfa
01:54:20 refuge in a flat for example it grandfa which happened many cases they a situation was that they found themselves when they opened the front door to the landing they couldn't see his hand in
01:54:32 landing they couldn't see his hand in front of the face darkness so they were then trapped in the flat for what maybe an hour or so act Grenville and they were been facing a situation like this was a slowly building up dose right I
01:54:46 was a slowly building up dose right I think we're nearly there so for every any given arias now for any given smoke visibility how far can people go before they Maximus fix you these examples that I've
01:54:59 Maximus fix you these examples that I've shown you far scenarios and effects can be useful to estimate the likely expressive and effects on Greta documents exposed in similar situations including staying in flats with rapid
01:55:12 including staying in flats with rapid smoke slow smoke and going into lobbies but because the time concentration curves of smoke gases throughout the ground fall we don't have an information
01:55:23 ground fall we don't have an information like a deer for the tests is there another way we can come at it well one set of information we do these descriptions by the witnesses of the smoke dist in toxicity are different
01:55:34 smoke dist in toxicity are different times and locations from the witness statements on the nine nine nine emergency calls because the ratio of smoke density to concentration is a constant I can use this to predict what
01:55:48 constant I can use this to predict what would happen I'm going to speed up a bit and show you this graph so basically this is a an image of the visibility compared with time to collapse so
01:56:00 compared with time to collapse so because the smoke visibility and the other toxic gases are tracking together in the fire if you know if the smoke is dense you know there's a high concentrations of the gases it's as if
01:56:12 concentrations of the gases it's as if the visibility is good then you have low concentrations so if for example you had somebody in a flat in Grenville and they could see for three meters they said oh they were smoke coming in the flat I was
01:56:24 they were smoke coming in the flat I was there for half an hour but I could see I could see across the room how dangerous is that smoke well this graph tells me that after say half an hour you were
01:56:35 that after say half an hour you were nowhere near half a dose that would cause incapacitation but they don't say that person having been there for half an hour then steps out onto the landing and they can now can't see the hand in
01:56:47 and they can now can't see the hand in front of the first and then you come onto this curve you then only have two or three minutes further before you would collapse so I think it's going to help us to see how exposure different smoke densities correlates with the
01:57:00 smoke densities correlates with the asphyxiant gas concentrations at different times and location
01:57:06 so in summary using data from past incidents and full scale experiments coupled with Fe D physiological methods for calculating time to incapacitation and death it's possible to identify a
01:57:19 and death it's possible to identify a set of fire explosion scenarios occurring at Grenville and the likely effects on occupants by expressing the fe d terribly as a function of visibility as I did in the last slide is
01:57:30 visibility as I did in the last slide is spotter estimating the hazards from irritants smokin asphyxia gases at different times and locations are Grenville from witness accounts of visibility I reported toxicity symptoms sent
01:57:43 I reported toxicity symptoms sent carboxyhemoglobin measurements in the blood of some Grenville fatalities related to that from previous incidents can be used to determine the extent of exposure of these fatalities to toxic
01:57:55 exposure of these fatalities to toxic smoke or heat and burns and that's the end of that presentation thank you thank you very much would you like another
01:58:06 you very much would you like another break at this point have you got to load something else on there I want the next presentation yes would this be a good time to have a short break it is enough just to my benefit how long is the next
01:58:19 just to my benefit how long is the next presentation do you think just under an hour on the front right I'm hoping we can at least get through that round before lunch well if we came back at five past twelve
01:58:31 well if we came back at five past twelve yeah you reckon you'd finish I want to talk yes I've got the third presentation that looks like that's to go which is a shorter one we'll get on to that yeah we
01:58:46 shorter one we'll get on to that yeah we can't push people too hard they need their lunch thank you for it well we'll stop no until five past twelve yes again please don't talk twin on the button or evidence one arrived to the room
01:58:56 the room and gave you the outer shoe look after you that's right
01:59:12 all right five plus 12 she's thank you
01:59:50 you
02:05:49 you
02:13:13 thank you
02:13:18 mr. chemin ah I hope Fester per second presentation has been loaded should start but before he begins can I just repeat the trigger warning that we gave this we're gonna do some more turn
02:13:33 this we're gonna do some more turn getting disturbing to us and the nature of the presentation may be distressing in itself that's right thank you for making that clear right I'm ready to go on professor yes I'm good thank you okay
02:13:46 on professor yes I'm good thank you okay so a second presentation I want to address some of the effects right but it to actually be happening in grain fill incident and before I get into the detail of this I just want to remind you
02:13:59 detail of this I just want to remind you of some slides that's an information that dr. Lane put up about the five requirements in the building regulations and the one I want to focus on particularly you remember she was she
02:14:11 particularly you remember she was she told us that there has to be adequate means of escape but essentially each flap should be a far existing box and that the fire should not be to get out of the flat the lining should not propagate fire and there shouldn't be
02:14:23 propagate fire and there shouldn't be external fire spread but the one don't want to focus on is the means of warning and escape the building shall be designed and constructed so there are appropriate provisions for the early
02:14:34 appropriate provisions for the early warning of fire and appropriate means of escape in case of fire from the building to a place of safety outside the building capable of being safely and
02:14:45 building capable of being safely and effectively used at all material time so that's a fundamental requirement of building regulations now in a grenfell the design attempted to achieve that partly as I said by the fire resisting
02:14:57 partly as I said by the fire resisting construction but we do have our means of escape we had detection in each flat if there were detectives in the flats and then you have corridors hallways in each
02:15:09 then you have corridors hallways in each flat to enable a person to escape away from the fire in their flat in safety into the lobby the front flat entrance door is a fire existing door which
02:15:21 door is a fire existing door which should resist both fire and smoke contamination of the lobby so once you're in the lobby should be in a smoke-free environment then we have an extra layer of protection before we come to the
02:15:32 protection before we come to the concrete protected shaft of the stair as a smoke door fire door on the stair itself so we have these provisions but Grenville but we also have a state
02:15:46 Grenville but we also have a state policy and a statement policy means that people are encouraged basically to remain in their flat most of times and there's a lot of statistics on this a huge many times when there are fires in
02:15:58 huge many times when there are fires in a flat in a home or at our block it's restricted to that single or in a tower block to a single dwelling and so there is no need in many cases for people to evacuate however important point is that
02:16:11 evacuate however important point is that should things change so that they become uncomfortable because of the situation or because safe smoke or fire comes through another flat in the block they should still be this preserved escape
02:16:23 should still be this preserved escape route out that should be free of smoke and fire at all times I clearly this these requirements were failed all of them at some time a grand fall and for
02:16:34 them at some time a grand fall and for my investigation then I'm trying to decide how and when smoke and flames penetrated individual flats are the beginning particularly on the east side of the tower so we've got a column of
02:16:45 of the tower so we've got a column of flats basically flat six on each floor but are first affected by penetration from the exterior fire moving up the structure when and how did that happen
02:16:56 structure when and how did that happen how'd intended dense smoke penetrate into the lobbies and how did this affect the behavior escape capability and survival of the occupants when did it get into the stair and have effects in
02:17:07 get into the stair and have effects in the stair and then when later other flats were penetrated by fire how did that happen and what did it do now I just want to briefly talk a bit about the stair at Granville and why do I want
02:17:20 the stair at Granville and why do I want to do that well interrupts I just wanted to be clear with because this professor person slides are not coming up Oh Beckett oh well I was waiting to see what happened I was playing on the primary great
02:17:33 I was playing on the primary great Gaston then you can't see anything
02:17:39 and so mr. chairman and that it's it's being looked into my dear technical how many slides have we missed professor I'll just I won't talk to them I'll just
02:17:51 I'll just I won't talk to them I'll just flash them up when it comes back so to remind people yeah but are we talking about three or four three four yeah do that that's good idea sorry let me get away
02:18:10 now mostly text slides anyway and so do you have already
02:18:33 that's a yes all right presentation mode
02:18:44 mm-hm yep away thank you yeah this reflects the building regulations yeah and this is what you've just been telling guys we could probably
02:18:55 just been telling guys we could probably go on yes so that's that's the one of that means of escape yeah and this is the diagram of the layout you're showing the various points I mentioned mhm under
02:19:06 the various points I mentioned mhm under server I'm saying is that these are the what I'm trying to determine and I will talk a bit about the stair the reason I'm interested in the stair is because my mission if you like is to consider
02:19:19 my mission if you like is to consider the effects of exposure to toxic smoke one place you can be exposed to toxic smoke is in the stair and whether or not you are able to get down the stair without collapsing depends partly how
02:19:30 without collapsing depends partly how long it takes you to get down the stair and so if for example we assume that there are approximately two hundred and ninety three persons in Grenville tower
02:19:41 ninety three persons in Grenville tower on the night of the fire let's suppose that around about one o'clock they'd all simultaneously attempted to get into the stair and come down the building how long would have
02:19:52 down the building how long would have taken them to do so if that would have taken an hour and that smoke I filled the stair then that's a long time to be exposed so how long would it would have
02:20:03 exposed so how long would it would have taken well I've done a lot of work on evacuations and drills and things like that so for a building designed for simultaneous evacuation approved
02:20:14 simultaneous evacuation approved document b assumes in its calculations would healing within the document a standing density on the stair of four persons per meter squared so the idea is that the population could move into the
02:20:25 that the population could move into the stair for such a building stand on the steps and on the landings in the stair and be in a protected space but that would be very dense packing and you wouldn't be able to move you have to wait for the building to clear from
02:20:37 wait for the building to clear from below you now in practice when I would carried out experiments of this kind I found that people will not pack to that level of density and it typically will
02:20:48 level of density and it typically will crowd if you like to the extent of two persons per square meter now that density you would still be have to move be moving quite slowly came down in a group but you'd be able
02:21:00 came down in a group but you'd be able to move reasonably well now at the packing density of two persons per square meter there would be room for about four hundred and sixty persons in the ground falls there and we've got two
02:21:12 the ground falls there and we've got two hundred and ninety so you can see that that would be twenty persons before if the 293 at Grenville 20 and that's thirteen per floor which is one person roughly per meter so even in the extreme
02:21:25 roughly per meter so even in the extreme case in where everybody went in at once there'd be plenty of space and free movement available physically in the ground for stay now my colleague professor Galya who haven't heard from
02:21:37 professor Galya who haven't heard from yet but it's working for Phase two he will be doing an in-depth analysis of this but I'm just pointing these basic things out so even the extreme case this there'd be plenty of room in a stair for
02:21:49 there'd be plenty of room in a stair for people to move freely now how long does it take to come down well when I was at Grenville I I tied myself coming down stair and I was wearing protective
02:22:00 stair and I was wearing protective clothing heavy boots sort of respirator we are very restrictive clothing and the time I was 73 years old and I found I was able to descend at a rate of 9.3
02:22:14 was able to descend at a rate of 9.3 seconds per floor which represents time to get to the bottom nominally of 23 floors in the very top of three and a half minutes so that's a person on their
02:22:25 half minutes so that's a person on their own in an empty stair descending on their own now but evacuation time of a crowd in a building we've got a 1 meter
02:22:36 crowd in a building we've got a 1 meter wide stair the maximum flow rate of people down the stair is calculated according to a fairly standard formula and for a 1 meter wide stair that would
02:22:47 and for a 1 meter wide stair that would be about 42 persons per minute could flow down out of the bottom of that stair and so if there were 293 people in the building that would represent a if
02:22:58 the building that would represent a if you like an ideal nominal evacuation time of the whole population to the lobby in seven minutes if they all suddenly went into the stair quite a short period of time now of course in
02:23:10 short period of time now of course in practice we have children elderly people someone disabled and that can they won't be slower and also they may block the stair to something but I confirmed it was able to
02:23:23 something but I confirmed it was able to pass somebody on grandpa stair and indeed many occupants report virtually the slow ones people coming past and on the stair so there was possible to overtake it was also possible they reported going past fire officers who
02:23:35 reported going past fire officers who really stairwell so although the single stare at Gretel was quite narrow there was a good handrail and the physical capacity was sufficient for all occupants to
02:23:46 sufficient for all occupants to evacuated safely within minutes if there had been some means of alerting them to evacuate such as for example a general tower alarm system which of course we didn't have so what do people do in
02:24:00 didn't have so what do people do in practice well it despite the lack of a general simultaneous alarm system in the tower
02:24:08 tower the majority of tower occupants became aware of the fire at a very early stage I get this from my studies of the Britnie statements um and they picked up
02:24:21 Britnie statements um and they picked up from a variety of cues which I've listed here but I won't read them all out this things like noises fire engines smelling smoke meat in some cases there are detectors going on and they all many
02:24:32 detectors going on and they all many many people are on all floors even right at the very top realized at a very early stage there was something serious going on and many of them decided to evacuate at that point and some of them decided
02:24:48 at that point and some of them decided to go down just to investigate because they were worried about what might be happening below others made the decision that was serious and to get out and I've tried to summarize this and depict it in
02:25:00 tried to summarize this and depict it in this slide here on the right now one thing I realized when I started to read these statements and study the evacuation times that were recorded was
02:25:13 evacuation times that were recorded was that there was a very different set of behaviors on the top sixth floors of the tower floors 18 to 23 and they was a lot of interaction between
02:25:25 they was a lot of interaction between people Oh within and on between those floors so it makes a kind of group a little community if you like about doing certain things and so on this graph here
02:25:37 certain things and so on this graph here I've plotted the number of people who are in those top plus this red line here the top six floors and their evacuation from the tower and then because I've
02:25:49 from the tower and then because I've done the top six floors I then went down the tower in groups of six floors so the next chunk the next group is floors twelve to seventeen which is the black
02:26:00 twelve to seventeen which is the black line and then flaws six to eleven which is the brown line that left me with two floors towards the bottom the fire floor for four and the floor above that floor farm it is the blue line and these two
02:26:13 farm it is the blue line and these two vertical lines here are quite important because the red line is the point in time when from studying the witness statements I believe that most lobbies
02:26:25 statements I believe that most lobbies became filled with dense smoke that people couldn't see through now obviously this is not a point in time it's a process but this provides a good
02:26:37 it's a process but this provides a good sort of anchor point from whence conditions smoke conditions became serious in the lobbies and what you can see here is that very very many now
02:26:48 see here is that very very many now these the times on here and not the times people exited the building there the times I've estimated from those times that they started so when they entered the stair wherever they were and
02:27:00 entered the stair wherever they were and I've done that using a very simple calculation so it's only an estimate where I've assumed that you descend at a rate of twelve seconds per floor so from that from the exit time allowing twelve
02:27:13 that from the exit time allowing twelve seconds per floor I can calculate the slightly earlier time at which the person entered the stair whatever floor they were on okay that's what's depicted here and what this shows is that many
02:27:24 here and what this shows is that many many people started to evacuate very early on and indeed nearly all these people here on these floors started to evacuate before
02:27:35 evacuate before there was significant smoke in the lobbies and they were able to make a effective at safety scent because there was virtually no smoke in the stair at that time but after that time the stair
02:27:50 that time but after that time the stair is still relatively clear of smoke but the lobbies are full of dense smoke so now we have a period where people are opening their flat doors and either deciding to brave going through the
02:28:02 deciding to brave going through the smoke or they or they state to dangerous lung and stay put people who did venture out into the lobby had great difficulty finding their way to the stair and a bit like Professor Jin's work they were
02:28:14 like Professor Jin's work they were there feeling their way and they described along the walls and some of them had several attempts had to go back to their flats maybe have some fresh air from a window and then they try again and eventually found their way to the
02:28:27 and eventually found their way to the door they did to stare opened it got into the stair and this is this period here and when they got into the stair they found there was some smoking stair but they could see several meters and it
02:28:38 but they could see several meters and it wasn't it wasn't too onerous and they were also able to descend safely but on floors top floors here there was a different kind of pattern of behavior
02:28:50 different kind of pattern of behavior that emerged which is something I'm I need to get into in a lot more detail to understand what was going on but basically a lot of these people did this did decide at a very early stage to
02:29:02 did decide at a very early stage to evacuate the tower and I believe what's actually happened here is that crucial in this was the behavior of people on floors 8 18 and 19 quite a lot of those
02:29:15 floors 8 18 and 19 quite a lot of those people decided to evacuate they started to come down and then for some reason they just turned back and went back up and they went back up to the 23rd floor
02:29:27 and they went back up to the 23rd floor most cases and so instead of coming out of the tower they took refuge in in in other flats within the tower also affected were other people particularly
02:29:39 affected were other people particularly on floors 20 to 23 who had made a decision very early on I'm talking about before Oh 130 they decided things were getting bad they've been alerted by people probably
02:29:50 they've been alerted by people probably from flat-six who are having fire coming into their flats and they decided we ought to get out but when they went to the door to the stair to decide to come
02:30:02 the door to the stair to decide to come down they were confronted by this knot of people ascending whoo-hoo and and they said well there I've got some statements here they were saying oh I was going to go down the stair but these
02:30:14 was going to go down the stair but these people are coming up saying it's not possible to go down and anyway they were blocking the stairs so I was unable to do so
02:30:19 do so so quite a lot of those people also ended up staying either on their own floor or different floor taking refuge in flats who otherwise probably would have descended at that time this is just
02:30:36 have descended at that time this is just a summary of some accounts from different witnesses who described the conditions in the stair how they were able to overtake and various things like that I won't read these out but I just
02:30:47 that I won't read these out but I just want to like this this question of why people turned back and didn't come down is so crucial I think that we need to spend a little time thinking about it and so I forgive me I'd like to read out
02:30:59 and so I forgive me I'd like to read out a couple of statements and this is from Aaron mechons statement she was in flat 163 on the 19th floor now she left her flat I
02:31:10 19th floor now she left her flat I estimated approximately Oh 1 27 when conditions in they'll both the lobby and the stair were reasonably good but she ended up going back and then tried again a few minutes later so I just read this
02:31:23 a few minutes later so I just read this out Amar's relative had remained on the landing and started to follow me in my children down the stairs we had not gone far down the stairs though I do not
02:31:34 far down the stairs though I do not remember which floor we'd reached when we met a group of approximately 10 people on the stair world they all seemed to be other residents the tower someone below us shouted out go back go
02:31:46 someone below us shouted out go back go back the group including me my two girls and a MPH relative all started moving back up the stairs ie up the tower I got to the top of the stairs on my floor I did not want to go
02:31:59 stairs on my floor I did not want to go back into my flat so I decided to ignore the advice that had been shouted in the stairwell to go back up and I headed back down the stairs with my daughters the next bit is also very important there was no one on
02:32:12 also very important there was no one on the stairwell at this point so this knot of people had gone and the stair was now empty or relatively empty after we were walking down the stairs the smoke was becoming thicker and thicker so this may
02:32:24 becoming thicker and thicker so this may be a factor it was dense and dark gray but I could see through it I was able to breathe without any difficulty now there may be a number of reasons why this group of people turned back and of
02:32:36 group of people turned back and of course but as you if you're near the top of the stair or the tower and you're coming down towards the fire it's a very frightening situation you don't really know what's going to be happening below
02:32:48 know what's going to be happening below and this may be why particularly the upper part people were more reluctant to come down but it could also be that they were starting to encounter a little bit of smoke in the stair and thinking where it's going may be a lot worse lower than
02:33:00 it's going may be a lot worse lower than but what for whatever reason this was a crucial event in the incident this is a statement of doctor named Ely we immediately went to the staircase and opened the emergency door at that point
02:33:13 opened the emergency door at that point we intended to walk d'azyr again at about Oh 1:27 part of me at that point we intended to walk down the stairs and leave the building we saw a lot of people walking up the stairs I can't
02:33:24 people walking up the stairs I can't remember how many people were walking up it was a lot enough to me we could not go down stairs it was people constantly walking up there was hazy smoke in the
02:33:36 walking up there was hazy smoke in the stairwell at that point they looked normal walking up stairs not screaming and running or anything unusual we didn't talk to anyone I was a bit stunned at that point people walking up stairs wasn't something I expected to
02:33:49 stairs wasn't something I expected to see at this point our lady comes out of flat 193 and invites her know I think so cousin to take refuge with them in one flat 119 of course with smoke from that
02:34:01 flat 119 of course with smoke from that time they wait they stayed there for some time and then eventually you know cousin came down 0:03 you know some a long time later so from oh one thirty now so this is
02:34:15 so from oh one thirty now so this is this is appear before oh one thirty but from oh one thirty most lobbies are filling with dense smoke but much less in the stair the snare was increasing that people were still able to descend
02:34:26 that people were still able to descend safely if if they were able to reach the stair but they had to go through the lobby first which was very dead badly smoke from Y 132 Oh 147 a further 31
02:34:37 smoke from Y 132 Oh 147 a further 31 persons entered the stair and evacuated from different floors up to the 20th up to about oh 149 and the last person to come up from that height at this point was Petra to Oliver
02:34:49 was Petra to Oliver so what her statement is quite interest portent in this respect then there was a period of about 29 minutes I'm just going to go back to my previous there
02:35:06 going to go back to my previous there right this period here see everyone is coming down and suddenly there's appeared when nobody's leaving for about 29 minutes straddling the two o'clock
02:35:17 29 minutes straddling the two o'clock point and then people come down in ones and twos at intervals over the rest of the period of up to actually up to 8 o'clock or the last person came up
02:35:35 so further 31 people came down at small numbers and they were all though they were smoking stare they were able to
02:35:47 were smoking stare they were able to come down safely but the stood the smoke in the stairs increasing all the time and there's one very useful account where somebody describes at some point coming into the
02:36:00 describes at some point coming into the stair which was relatively smoke-free and seeing people coming in to the stair up floors above and below and as they were opening the door from the lobby so the smoke is coming in to the stair all
02:36:12 the smoke is coming in to the stair all levels so after this period occupants after this period so we're now past two o'clock and I'm sort of put a line on my graph of two o'clock and I'm saying
02:36:25 graph of two o'clock and I'm saying basically that up to somewhere just before around two o'clock the stair itself was reasonably safe to come down they was smoking it but it wasn't too
02:36:37 they was smoking it but it wasn't too bad and people quite successfully came down during that time after two o'clock sometime after 2 o'clock when the next people start to come down by this time
02:36:48 people start to come down by this time the stair is really quite hazardous and it has much denser smoke but also high concentrations of asphyxia gases so from
02:36:59 concentrations of asphyxia gases so from about 2:00 o'clock the stair is now much more hazardous as well as the lobbies
02:37:11 so grenfell occupies descending in dense smoke after two o'clock so they were built they were able to progress rapidly by holding the handrail for a few people
02:37:23 by holding the handrail for a few people so yes it's a bit this slide I'm addressing once I've talked about speed of descent in the stair when it's clear but one of the problems going back to Professor Jean is that if the stair gets
02:37:36 Professor Jean is that if the stair gets full of smoke we'd expect people to slow down load and that was certainly the case when people trying to find their way through the lobbies but in the stair itself we found in experiments that if
02:37:47 itself we found in experiments that if you have a guide like a handrail you can still progress quite rapidly even if you can't see hardly anything and people reported that and indeed for some of these people we can make an estimate of
02:38:00 these people we can make an estimate of how long it took them to descend where we have the end of their last nine nine nine called timed and we have the time they got to the lobby so we know the
02:38:11 they got to the lobby so we know the time between the two and this tells me that released for a few of these people that we have that those two bits of information they were descending generally quite rapidly in the stair at
02:38:22 generally quite rapidly in the stair at this time now I want to go back to so that's the situation with the stair all right up to up to i-130 both the lobbies
02:38:34 right up to up to i-130 both the lobbies and stair reasonably clear Navigo between Oh 113 Oh 200 very bad conditions than lobbyists but reasonable conditions in stair after 200 you've got
02:38:46 conditions in stair after 200 you've got hazardous conditions both in the stair and in the lobbies I now want to talk go back to what's happening in the flats and this is a sort of brief example I'm looking at flat 16 and I don't think
02:38:59 looking at flat 16 and I don't think I'll read all this but basically flat 16 is just an example of a simple basic domestic fast scenario typical of the sort I described with my previous lecture so mr. kabiri realized earlier
02:39:13 lecture so mr. kabiri realized earlier there was a fire I think his smoke alarm went off he got people out he closed the door he warned the neighbors everybody evacuate and call the fire brigade everything was alright but what happened
02:39:26 everything was alright but what happened next well you then got this big plume of smoke coming out of his flat and flowing up the side of the tower and here of it I've got some pictures from Professor
02:39:38 I've got some pictures from Professor Bisbee's presentation showing all this smoke now this smoke is is important I was interesting because as smoke flows up the outside in a clue as you can see
02:39:50 up the outside in a clue as you can see there it entrains air air mixes with it and it becomes extremely diluted so although it looks a bit unpleasant if you like it's not particularly hazardous
02:40:01 you like it's not particularly hazardous and some of that smoke coming from fires low in the tower is going to find its way through gaps penetrations open windows whatever into flats are finished
02:40:12 windows whatever into flats are finished there so people were reporting smelling smoke some didn't let smoke alarms were going off and people were being kind of warned if you like becoming aware the fire partly because of this but at this point it may be causing a slight haze in
02:40:24 point it may be causing a slight haze in your flat but nothing terribly dangerous apart from flying up the outside there may be some smoke coming in inside and some of it may be coming from flat 16
02:40:36 some of it may be coming from flat 16 into the lobby and then into the stair but it all may be moving through other kinds of penetrations between floors and I think other experts are going to be
02:40:47 I think other experts are going to be talking about these those in more detail there are a number of routes for smoke spread but I believe that on in the most the lobbies at this early stage the main source of smoke was coming from flat six
02:40:59 source of smoke was coming from flat six on each floor finding its way into the lobby
02:41:06 okay now we get to the point where flames ignite the exterior cladding and insulation outside flat 16 so this is at about oh one fifteen hours and then it
02:41:18 about oh one fifteen hours and then it as professor Bisbee has described it rose goes rapidly up a side reaching the 23rd floor Oh 124 and the exterior fire
02:41:29 23rd floor Oh 124 and the exterior fire then penetrates most of the kitchens of flat six in each on each floor in in sequence and this spreading plume is shown in these professor Bisbee's
02:41:40 shown in these professor Bisbee's photographs here
02:41:44 so what then happened at each flat as the fire rose outside to it right the
02:41:55 the fire rose outside to it right the first thing that's happened is that smoke is generated that is generated mainly outside the flat it's not thin smokers are described because it's near the source it's dense and undiluted so
02:42:07 the source it's dense and undiluted so it's thick dense smoke and it will have contained a significant amounts of toxic yeah a six unit gases there are two possible main routes of dense smoke entry and flame penetration into flats
02:42:20 entry and flame penetration into flats as the exterior fire reaches each floor from below one is from the exterior fire plume involving the cladding and insulation and smoke from that cut and
02:42:33 insulation and smoke from that cut and flames coming through open windows the kitchen ventilator openings which have been mentioned by a number of witnesses and through sort of gaps and holes in windows and especially where you could
02:42:46 windows and especially where you could early partial glazing failure and that's reported by a number of people they say the flames camp outside and then part of my window further out when one because I think they said the whole window
02:42:58 secondly from an insulation fire burning in the void behind the column as I mentioned earlier and spandrel cladding entering the flat through penetrations around the window frames and you'll
02:43:10 around the window frames and you'll remember prefer dr. Lane describing that is a diagram from her report showing the room
02:43:17 room by which this happened and this Denson is dense smoke with highly toxic gases the next stage is dense smoke from
02:43:29 the next stage is dense smoke from combustible materials structural material still not the contents of the flat of the window surround adding to the flame and smoke development inside the flats around the windows especially
02:43:41 the flats around the windows especially the flat six kitchen and possibly the eastside lounge windows and this picture here from dr. lanes report shows how the
02:43:52 here from dr. lanes report shows how the fire has come in around the window and started to involve the PVC and other materials of the window around the window frame and that's going to be a source generating more toxic gases and
02:44:04 source generating more toxic gases and smoke into the enclosed flat and then finally the flames the fire may spread to involve the flat contents starting
02:44:16 to involve the flat contents starting with combustible contents close to the window such as blinds and curtains and that was reported by a number of people and then spreading and this is where it gets really serious to involve things
02:44:28 gets really serious to involve things like upholstered furniture and other items I haven't seen that particularly described by people so once you get to this point you have the danger of having
02:44:39 this point you have the danger of having a serious fire in the room that's been penetrated and what happens next depends a lot on what happens to the glazing and
02:44:50 a lot on what happens to the glazing and whether that windows fall out or whether remain intact particularly where the windows fall out there is a danger this fire will progress rapidly to flashover
02:45:02 fire will progress rapidly to flashover or at least a very serious fire and I think I've captured this on this this is an image 3 from professor business presentation and you can see here this
02:45:15 presentation and you can see here this is at us this is taken between 156 and 223 closer to 223 according to his slide and it's taken looking at the east face
02:45:26 and it's taken looking at the east face of the tower and so at this point the I was already gone all the way up the flat-six column here and it's now moved laterally to more like the flat one
02:45:37 laterally to more like the flat one location this bright bright flames here and here are basically the cladding and insulation burning outside those flats but here most of that has stopped
02:45:49 but here most of that has stopped burning has gone till you see these dark marks here then you've got these bright outlines of windows so this looks to me very much like we have serious fires
02:46:00 very much like we have serious fires inside these flats involving the flat contents by this time in the fire but I mean you know this is something that the other experts are going to be very
02:46:12 other experts are going to be very knowledgeable interested in and will be looking into much more detail in in stage 2 of the inquiry so from first
02:46:24 stage 2 of the inquiry so from first again from first becoming aware of fire the flat occupants were repeatedly faced with this difficult decision stay or go I mean live affected by different considerations and experiences but the
02:46:36 considerations and experiences but the expense extent of exposed to smoke or flames would be an important factor at some stage in some cases encouraging people to get out others stages preventing it so if we think of what's
02:46:50 preventing it so if we think of what's happening in flat 6 as the early stages of development as fire penetrates flat 6 on any floor it's likely if it's still going to be similar to these domestic growing fire scenarios I've already
02:47:01 growing fire scenarios I've already described to you except that instead of the fire starting in an armchair or sororal clients it's now starting in the window surrounding the external materials so the pattern though the
02:47:15 materials so the pattern though the pattern of penetration did well look that so the flat six occupants were alerted by a rare variety of cues in some cases their smoke alarms went off
02:47:26 some cases their smoke alarms went off so the fire has just started to penetrate and now they're aware most people in flat 6 became aware quite quickly there was something very bad going on if you read their account there
02:47:39 going on if you read their account there was some
02:47:41 was some variation it's a lot of variation between different flats in fire development and this shows up in the witness report so some people described
02:47:52 witness report so some people described flames appearing at the window as their first thing that happened when they came into the kitchen to look to see what was going on other people woke up to find the flats full of smoke before there was
02:48:04 the flats full of smoke before there was any fire penetration from the outside there's a variety of different experiences you're partly dependent upon what happened to this ventilator assembly partly on whether or not they had their windows open it was warm
02:48:15 had their windows open it was warm weather and various other factors but the general pattern is of rapid smoke filling of flat-6 people being aware of it from an early stage and realizing they were in all the
02:48:28 stage and realizing they were in all the way up the tower though they're in a very serious situation and so what did they do well they all evacuated sometimes with no shoes on partially
02:48:39 sometimes with no shoes on partially dressed they got out very quickly and they were able to do so now the important thing here is the flatstick
02:48:50 important thing here is the flatstick documents left their flats before there was any significant smoke in the lobbies and a large number of them just carried
02:49:01 and a large number of them just carried on and evacuated the tower but others as we heard didn't come down the tower they took refuge elsewhere in power in other flats sometimes on other floors where
02:49:14 flats sometimes on other floors where some flat-six document stated they left their flat six doors open and an open door would be a route for smoke flow into the lobbies I'm looking to find out when and how all those lobbies became
02:49:28 when and how all those lobbies became filled with dense smoke at about oh 130 which prevented other people from evacuated and so I believe that flat-six was probably the main source now obviously if the flat-six door is open
02:49:40 obviously if the flat-six door is open it's an easy route for smoke to flow from the flat into the lobby and so there are questions then about how those doors performed and the self closes
02:49:52 doors performed and the self closes whether whether the those doors were shut after people had just come out and left me but there are a lot of accounts of these doors remaining open and smoke flowing out I'm
02:50:03 remaining open and smoke flowing out I'm quickly filling the lobby from the ceiling down with dense smoke now some people actually stated that they did in fact close their flat doors before they left and that we would hope that that
02:50:16 left and that we would hope that that would reduce the speed of filling of the lobbies with smoke and I'm in the process of analyzing to analyze these statements but my impression is that
02:50:27 statements but my impression is that even where they lobbied where the flat doors were shut there was still significant leakage of smoke that filled those lobbies with quite dense smoke quite quickly so I've been necessary in
02:50:40 quite quickly so I've been necessary in Phase two to look more closely into it
02:50:46 of course after they left the flats the fire was continuing to develop in each flat and so some of these flats were completely burned out now of course during the later parts of this fire as
02:50:57 during the later parts of this fire as we come to more towards two o'clock its these interior fires are getting very serious and most of the smoke and toxic gases are generated in those flat fires and finding their way partly out through
02:51:08 and finding their way partly out through the windows through the open window plume but partly into the lobby are coming from the flat contents burning increasing proportion and some of these
02:51:19 increasing proportion and some of these are going to reach very high temperatures and and to flashover so when we look at the pattern so this table 6 from my report shows the number
02:51:31 table 6 from my report shows the number of fatalities in each flat and the way I've kind of organized this is that this is the sort of west side of the tower and this is the east side of town and
02:51:42 and this is the east side of town and the thing that really leaps out at you is that nobody died there are no remains no recovered from any flat 6 so all these people were confronted with fire
02:51:55 these people were confronted with fire coming in through the windows all the way up the tower rapidly deteriorating conditions in their flat but they were able to evacuate the flat not this sort of the tower but they evacuate the flat into a relatively smoke-free law
02:52:07 into a relatively smoke-free law in many cases they came down fire also spread quite rapidly to flat one and in general most people left flat one apart from flat 201 which is a case where a
02:52:21 from flat 201 which is a case where a lot of people were with some time and then that what also shows in this analysis is that ironically it's the
02:52:32 analysis is that ironically it's the least affected flats that then become the most dangerous because when people took refuge typically in flat 3 which is in the southwest corner of the block was
02:52:45 in the southwest corner of the block was the last place to be affected by fire spread around the town and so they remained there often for an hour or so before they were forced to evacuate or before the fire got to them and so they
02:52:59 before the fire got to them and so they were in the situation where they stayed and then got exposed so up to o1 30 most
02:53:13 and then got exposed so up to o1 30 most flats up in flat 6 on each floor and possibly flat one were generally smoke-free from Row 1 30 to 35 we have lobbies of various floors filling with dense irritant smoke reports of almost
02:53:24 dense irritant smoke reports of almost zero visibility could not see hand in front of face difficulty breathing a note in smoke some people then try to go through this smoke feeling their way around the walls I've mentioned and this
02:53:37 around the walls I've mentioned and this is like I've had high concentrations of in the lobbies of high concentrations but nothing in the stairs but fortunately it doesn't take very long to
02:53:48 fortunately it doesn't take very long to get across the lobby evening so some people did report feeling dizzy while they were in the lobby occupants who then entered the stair between o1 thirty and forty nine found much clearer
02:53:59 and forty nine found much clearer conditions though in the lobby not totally smoke-free I'm variable to descend safely without without collapsing and I put a few examples in here but one person in
02:54:10 examples in here but one person in particular I want to talk about is Abram a BB and his wife because this is an example of a couple who came down only from the seventh floor at O 148 exited
02:54:24 from the seventh floor at O 148 exited over 148 eventually but in his statement he recounts coming down the stair in a very early stage in reasonable conditions but then finding thick black
02:54:36 conditions but then finding thick black smoke in the stair between the fourth and fifth floor and an open door to the stair with a hose going through it the smoke is flowing out from firefighting activities from a flat into a lobby and
02:54:47 activities from a flat into a lobby and then into the stair and he saw this big cloud of thick black smoke in this area and he said something along the lines of as he was frightened to continue down
02:54:59 as he was frightened to continue down the stair but he was kind of preparing himself to go through he knew he only had a couple of floors to go down but his wife who was a little bit higher up called him back
02:55:10 called him back Sohyun his wife then ascended back up to their flat until their firefighters came up and encouraged them to leave and so they came down again the second time they came down the stair is now got more
02:55:24 they came down the stair is now got more smoke in it but they were kind of more confident because the firefighters had told them they could come down so they came down and but he does say that by the time he got to the fourth floor by
02:55:35 the time he got to the fourth floor by now the smoke this smoke as he'd encounter before it now cleared somewhat so maybe but this point the firefighting operation and there had ceased in the door being closed branislav flute kicker
02:55:49 door being closed branislav flute kicker was one of the last people in this group to come down with his flatmate at OU 149 thick smoke in the lobby relieved to find less smoke in the stairwells as his Oh 149 20 could see through it more gray
02:56:04 Oh 149 20 could see through it more gray than black and he was more as carrying clarita Gavi me so which requires a lot of physiological effort and yet he was able to do it through the conditions at
02:56:16 able to do it through the conditions at that time so this demonstrates to me that although there was some smoke in the stair at this time you could still descend in reasonable safety after a 130 many occupant stay
02:56:27 safety after a 130 many occupant stay put at least a fact affected flats are those in the three position mostly smoke three conditions at first but then gradually filling and the flat Occulus
02:56:40 gradually filling and the flat Occulus then took first measures to try and limit smoke entry and it seems at this time that most of the slow smoke filling is coming from the lobby so again we've got this issue of smoke penetrating
02:56:53 got this issue of smoke penetrating partly around possibly partly around the flat entrance doors so at one stage you've got smoke coming from flat-six around the flat six entrance door even
02:57:05 around the flat six entrance door even if it's closed and as sister described bust up somebody into the lobby now we've got the lobby full of thick smoke clear conditions in a flat but smoke coming in the opposite direction from
02:57:16 coming in the opposite direction from the lobby into the flats so obviously there was some leakage going on also people some people described smoke coming through pipe penetrations between their platinum lobby and various other routes but they anybody trying to leave
02:57:33 routes but they anybody trying to leave now in difficult so so this is now a scenario where they're stuck in the flat and they have something very like the people in the closed rooms at Rose Park slowly taking up carbon monoxide over a
02:57:44 slowly taking up carbon monoxide over a period of an hour or two and because the conditions of constants are very low I don't believe that cyanide would have been a significant factor in this slow buildup of the co
02:58:02 now after 2 o'clock if occupants attempted to evacuate into the lobby they were exposed a very high concentration of smoke co and possibly cyanide in the lobby and stair also
02:58:15 cyanide in the lobby and stair also capable of causing collapse within minutes the outcome for these people I believe depended on the dose accumulated while in the flat so if you were in a flat that had low smoke or you left
02:58:28 flat that had low smoke or you left within a short period you would be able to descend the stair within a few minutes without collapsing and some people certainly described being in
02:58:39 people certainly described being in trapped in a flat and but being able to open the exterior windows and keep some of the smoke out the flat because it's before the fires come around to them so
02:58:50 before the fires come around to them so the conditions in the lobby were definitely hazardous so the escaping occupant summit them experienced zero visibility breathing difficulties in pain and as they descended they reported
02:59:01 pain and as they descended they reported being affected by this fixing gas is feeling weak and dizzy in some cases collapsing on the stair but as the descent of people at various time shows
02:59:12 descent of people at various time shows it was not impossible to descend the stair far as I could see at any time since some oculus succeeded in doing third intervals from all floors up to almost 8 o'clock I want to talk a little
02:59:28 almost 8 o'clock I want to talk a little bit now about the blood toxicology now this image on the right here is not in my phase 1 report but these these are objective data from the toxicologists
02:59:41 objective data from the toxicologists that it will not change so I feel we can have a look at it now I haven't identified any individual people here but again I think this is very useful
02:59:52 but again I think this is very useful because it confirms again that people were being overcome by smoke and toxic gases rather than by heat because as you can see all these numbers are in the
03:00:04 can see all these numbers are in the very high range apart from this one who was in this very low range but that was an individual who was alive rescued alive and taken to hospital
03:00:15 alive and taken to hospital and of course would have been given oxygen on the way to hospital she washed out see her from his blood also there was a problem with the sample a toxicology report it uncertainty about whether that is a true reading then you
03:00:28 whether that is a true reading then you have two people who may have fallen from the tower who had but they had a significant dose so we can tell these two people had been exposed to quite significant smoke not enough to make
03:00:39 significant smoke not enough to make them think capacitated but they were exposed to some time before they fell and then crucially the purple bars here are from bodies in flats and you can see
03:00:53 are from bodies in flats and you can see that these are all in this high range where death is occurring due to inhalation of toxic smoke one exceptionally high in the 90 milli 90%
03:01:06 exceptionally high in the 90 milli 90% carboxyhemoglobin before that person died from the smoke and the black bars are from fatalities in the lobby or stair and you can see they also all well
03:01:19 stair and you can see they also all well up into this death from carbon monoxide essentially group so they've died from collapse and died from exposure to asphyxiate gases in the smoke if these
03:01:33 asphyxiate gases in the smoke if these persons found inside the flats had been overcome by heat and burns before they had time to collapse them as fixing gases I would have expected to see much lower blood levels than we actually are
03:01:45 lower blood levels than we actually are are seeing right I think in view of the time I will I will stop at that point that's a convenient point yeah is it right but this is still further to go on
03:01:59 right but this is still further to go on this part of the presentation I think we can leave that move on to the third one when when you're ready yes well should we stop now then and take time for lunch and I can say we will resume at 2
03:02:11 and I can say we will resume at 2 o'clock right it just gives you just as a yeah and again please don't talk to her on about your evidence break and she'd go to the air show Shula coffee
03:02:21 coffee okay all right thank you very much
03:02:41 thank you I took off the please