The Future of Fire Safety

GURU MADHAVAN

What does the British national anthem have to do with fire safety? Curious? Let's go back to May 1911. The famous vaudeville headliner Great Lafayette was billed to play for an audience of 3000 at the Edinburgh Empire. The show was underway, with his usual cast of horses, acrobats, fire eaters and stunning special effects. When, suddenly, something went very wrong as a stage lantern caught fire. Unaware of this disastrous diversion, the audience remained in their seats, awestruck. Backstage, the fire engulfed Great Lafayette's onstage crew. To make things worse, the distrustful Lafayette had locked the backstage door to block others from stealing his tricks. Ten people lost their lives, along with Lafayette, his mysterious body double,his horse, and his lion. Miraculously, though, not a single member of the audience was harmed. After the iron fire protection curtain fell, the conductor ordered the orchestra to play God Save the King, to signal the show's end and rouse the people to exit. Legend suggests that everyone evacuated in the two and a half minutes it took the orchestra to play the British national anthem. This theatrical tragedy of 1911 unintentionally created a design standard or a magic number. The presumed exit time from most built environments. In many ways, this is the key episode for modern day fire safety. So what better way to unpack its legacy than in Edinburgh with two leaders in Fire Safety Engineering: Luke Bisby and Jose Torero.

PROFESSOR JOSE TORERO CULLEN

If you look at the headlines…for example, a plane crash landed. You always find those headlines that say, you know, the people in the plane were very lucky because they managed to get out on time without recognizing that actually the whole evacuation of an airplane, you know, even the way in which the fuselage is designed, the way in which the chairs are treated and designed, all that is fire engineering.

PROFESSOR LUKE BISBY

How much do we care about fire safety in the built environment? How much do we value it, potentially, over and above other things? And so if we value fire safety engineering in the built environment, if we really mean it, then we are going to have to devote public resource to educating the people and we're going to have to change the way that we regulate the profession and start regulating individuals.

GURU MADHAVAN

Welcome to Create the Future. I am Guru Madhavan, your host for this Queen Elizabeth Prize for Engineering podcast. Join me in an exploration of our past and present toward building a more reliable and responsible future of fire safety. Luke and Jose, welcome to Create the Future. You both have something in common. You both play with fire. But fire is many things, you see, I mean, it's from a warm cup of tea and toast to James Watt's steam engine. Luke, let's start with you. What does fire mean to you?

PROFESSOR LUKE BISBY

It's a bit of a loaded question. I mean, fire obviously consumes a lot of my professional life these days. And, you know, I was born a structural engineer but now I spend most of my life, as you say, playing with fire, although not necessarily playing with it at all times. Most days, most of the time being an academic and having this sort of slight mental defect that I can't stop thinking about work, fire is on my mind all the time in different ways. It is my profession. It is what consumes me intellectually. It's what causes angst and worry and what motivates me to do the things that I do in my professional life.

GURU MADHAVAN

That’s a fiery start indeed, And Jose, what goes through your mind when you see fire?

PROFESSOR JOSE TORERO CULLEN

For me, fire tends to always be a concern. Not only from the perspective of what are the potential negative impacts that a fire can have on people and property and so forth. But also, I think one very important aspect is all the things that we put in place to try to avoid those negative impacts and how many times those things are not necessarily done in the most appropriate of manners. So, yeah, you walk into a building and my kids, my wife will go and say, well, you're always obsessing about where the doors are. You know, what the risks are. So, yeah, so fire for me is mostly a concern I will say.

GURU MADHAVAN

Now, how exactly does fire work?

PROFESSOR JOSE TORERO CULLEN

Well, I mean, you know, you can take the sort of technical standards and, you know, fire is…effectively starts with a chemical reaction that generates a lot of energy and has all sorts of negative products that come out of it. And in essence, you know, there’s the physics, you know, behind it. But fire is mostly a social problem. You know, it is something that tends to affect people, you know, many times in a fairly unfair and uneven way. And when we use the terminology fire as opposed to flames, you know, we always think of the negative side of it, which is sort of this unintended generation of this chemical reaction that can be so destructive.

GURU MADHAVAN

And what do we mean by Fire Safety Engineering?

PROFESSOR JOSE TORERO CULLEN

Yeah, I mean, Fire Safety Engineering…every single thing that we do involves, in one way or another, Fire Safety Engineering. So, from the buildings that we inhabit, the objects that we use on a regular basis, our computers, our lamps. You know, you will turn your computer upside down and you will see a marking that basically tells you to somebody has looked into how to make that computer safe so it doesn't burn in a fire. The clothes that you wear tend to be worked in a way or treated in a way that they actually prevent you from getting significant burns. And it is fire safety engineers who actually, technically speaking, should be devising, you know, all these mechanisms by which we actually master the potential negative impacts of fire. So we put all the technical knowledge to try to make sure that we do this in an efficient, effective manner and at a reasonable cost that enables things to be done without the hazards associated to the fire.

PROFESSOR LUKE BISBY

And, keeping in mind that I think the context of Fire Safety Engineering will change depending on the context that one is is working within, fire,F safetySengineering E isi the process of using whatever information you have to hand or can get your hands on in order to try to ameliorate the outcomes or mitigate bad outcomes - if you like - due to the effects of fire. We have people who work in Fire Safety Engineering who are focused on wildfires or forest fires and what they do and the things they think about is going to be different to the kinds of things that I would think about. You know, the world that I work in is largely buildings that are used by the general public. I have a particular set of concerns that I would think about in that context. And then you have people who might work in industrial settings, you know, on oil rigs or people who work in the marine industry on boats. People who work in the nuclear industry. People who work in very, very high end scientific physics facilities like CERN and places like that. And all of us are just essentially trying to make sure we're thinking about and mitigating the potential adverse outcomes that might arise if there's an unwanted fire. So, it ranges over a whole number of things. For me, as I said at the outset, I was born, if you like, as a structural engineer. So, I came into academia thinking about the way that structures react to fire and more recently that's extended into thinking about, you know, how people react to fire, how combustion happens, how the dynamics of fire manifests in a given scenario. And all of those things come into play in different ways, to different extents, for different people in different contexts. It's a really large, diverse discipline that requires you to somehow become comfortable with a range of topics. Everything from the social, the deeply social, right the way through to the deeply technical. And not necessarily to be expert in all of them, but to be able to have conversations, you know, thoughtful, careful conversations with people about all of them. That's one of the things that I find really exciting about it, is that diversity of thought that it requires. You know, you're not just doing one little thing.

GURU MADHAVAN

Luke, while you're at it, what are some everyday examples of Fire Safety Engineering that might surprise us?

PROFESSOR LUKE BISBY

When we're teaching Students, I often say, you know, who has interacted with Fire Safety Engineering today, which is a nice way of asking that question of undergraduate students. And they kind of look at you confused and they sort of say, “well, none of us have.” And I say, you went through a door, didn't you, to get into this building? And you'll go through a door to get out of this building. Did that door open inwards or outwards? And the answer is going to be influenced or probably dictated in a public building by the potential need to evacuate that building in case of fire. So the doorway probably opens outwards so that if there's a fire in the building, people get out rather than pushing against the door and staying closed. Right. So that might seem like, you know, a little irrelevant piece of the building to most people. But it's actually really important if a lot of people are trying to get out of that building in a hurry. And so we go through our lives experiencing engineering all the time, and rarely do we think about the choices that have resulted in the world that we're moving through. And that's true… that's true of all engineering, right? That's not just Fire Safety Engineering. Every time you use a car or get on an airplane or flush the toilet. It's absolutely everywhere. It's pervasive in our world.

GURU MADHAVAN

And as is the nature of it, I mean, engineering comes to the forefront only when there's a failure, and I think we'll get to that. Jose, why aren't we talking about Fire Safety Engineering more, given how critical it is as Luke just described? I mean, are there any misconceptions about it, particularly?

PROFESSOR JOSE TORERO CULLEN

Misconceptions? Yes, there's many. And I think they're very much related to the reason why we don't talk about Fire Safety, because the reality is that in areas of engineering, like Fire Safety, when you do your job appropriately, then everything works properly. I use an example quite regularly - if you look at the headlines of a scenario where, for example, a plane crash landed. You always find this headline that says, you know, the people in in the plane were very lucky because they managed to get out on time without recognising that actually the whole evacuation of an airplane, you know, even the way in which the fuselage is designed, the way in which the chairs are treated and designed, all that is Fire Engineering and it’s all Fire Engineered to give you one minute to get out of the plane. And when everything works out okay, then effectively everybody is safe. But we don't really recognize what is behind that and the reason why people are safe. If we didn't put all these provisions in place and we didn't put these provisions in an appropriate way, then we will have taken a much, much longer period of time to evacuate people. The fuselage would have failed a lot earlier. The fire would have grown a lot faster in the plane. So it is not about luck. You know, it is about the fact that it is engineered in an appropriate way. And I think that's where the misconception is. When things work out well and therefore they don't make the headlines, you know, we almost ignore the fact that there was an enormous amount of technical knowledge that was put in place to make those things work. And that ignoring the fact that this technical knowledge is put in place to make things work is where the misconception is. We take it for granted. If I walk into a room and ask people, “do you feel that you're safe?” They will look at me puzzled because everybody more or less feels that they're safe. They don't want any change, they don't want improvement, and they have no recognition of all the input that went into the design of that space for them to feel safe.

GURU MADHAVAN

Historically, most fire safety concepts of the Western world seem to be linked primarily to 17th century London, especially the Great Fire of 1666. You know, it gutted most public buildings and tens of thousands of dwellings and there's the city literally rose from the ashes. So Luke, do you want to talk about how, perhaps, Fire Safety Engineering grew from that episode ?

PROFESSOR LUKE BISBY

The Great Fire of London, what it did is it helped us, unfortunately by disaster, by example. And incidentally, the great fires of San Francisco and Edo and Baltimore, the same lessons at different times in slightly different ways…you shouldn't have a lot of combustible materials on the outside of buildings. You shouldn't have thatched roofs. You should make sure that buildings have a certain separation distance associated with them. You should try to make sure that they have stone or brick exterior façades. You should insert party walls, what we call party walls, which is perhaps a slightly weird name. But, essentially you fire harden the boundaries between individual buildings so that if a fire is in one building, it's contained within that building, it doesn't spread to neighboring buildings. So, you know, some of the fundamental ideas in fire safety are about separation distance because the heat can spread because bits of building on fire can float through the air to ignite neighboring buildings and because radiation depends on the view factor and hence the proximity of the fire source to the thing that's receiving the radiation. So, you don't have buildings in close proximity to each other and you try not to build them out of things that will burn where those things are likely to be exposed. And so if you walk around Central London, you are walking through what is literally the consequence of the Great Fire of London.

PROFESSOR JOSE TORERO CULLEN

Yeah, I mean, I think there is one very important thing that I think needs to be added to that is… So, we always talk about building regulations and the reason why we talk about building regulations when it comes to fire is because of the Great Fire of London. And it changed the problem from the urban conflagration to the building. So, in essence, everything that we learned from the London Fire, you know, was that if we managed to contain the fire into one building, then the fire brigades and, in general, the building itself can respond appropriately and therefore the fire becomes a manageable event. The moment that you lose the control over the fire and it starts involving other buildings, then it becomes an urban conflagration. Then you have very, very little capacity to control and during a scenario more like what happens in forest fires, responders can do as much as they possibly can but nevertheless they have very little capacity to change the outcome of such an enormous event. So, what we really, really learned was that we had to transform by means of urban planning an urban problem into a building problem. And hence we talk about building regulations. We don't talk about urban regulations. We talk about building regulations when it comes to fire

GURU MADHAVAN

From what we have talked about so far, could you please tell us who exactly is responsible for Fire Safety? I mean, is it architects, policymakers, engineers, residents?

PROFESSOR JOSE TORERO CULLEN

This is really a very, very good question. I think the first part of the answer is definitely not the residents. I think it’s one primary assumption when you talk about fire safety is you have to design buildings and you have to design aircraft and you have to design furniture and you have to design everything in a way such that you are excluding the user from any responsibility. I mean, obviously, you know, we all behave in a civil manner and we should be behaving in a civil manner, but we should have no expectations of competency from the user. So, the user in itself is not responsible for fire safety. The user is responsible, you know, for behaving in a civil manner. That's really all we can ask from the user. Now who is responsible? That is a real big question because, in essence, the responsibilities are divided. You know, you have the responsibility of designing, delivering and maintaining buildings and that is a technical responsibility that should be in the hands of engineers and competent professionals that really understand the technical intricacies of delivering a building that is inherently fire safe. Now, obviously, like all safety systems, we need to have redundancies and the fire brigades are the redundancy, you know, to the building design. So, in case something goes wrong, then firefighters can come in and try to support the safety of the occupants of the building and, you know, safety of the building in itself. But in essence, the responsibility of delivering an inherently safe building relies on competent professionals, in this case, competent fire safety engineers.

PROFESSOR LUKE BISBY

When we use this word responsibility, there's kind of two parts to the question. One is, you know, kind of like an ethical, moral responsibility question. And my answer to that question would be anyone who participates in any way in the design, delivery, maintenance of the built environment has, in my view, an obvious moral and ethical responsibility to try to make sure that the provision of fire safety is adequate for the people who are using the built environment. And then you have the question of who actually takes responsibility in terms of the law. And that's also a very interesting question because that question can only be answered within the context of the legal and regulatory systems, in any given jurisdiction, that support that delivery of fire safety. So, the extent to which and manner with which we might regulate the practice of professional engineering or architecture or fire safety engineering specifically are going to influence the question of who actually is taking that legal responsibility. And the associated liability is something that people should be thinking about quite hard in every jurisdiction because it has profound implications for the way that fire safety is or is not delivered.

PROFESSOR JOSE TORERO CULLEN

If I may, to add something briefly, I mean, I think that that is a really important point. The one that Luke made, because, you know, while I will always insist that it is the Fire Safety Engineer who has the responsibility for fire safety, what happens in many regulatory frameworks is that their responsibility gets delegated to others. So, if a problem, for example, is just a home - a very simple problem - the architect might take that role of the Fire Safety Engineer. They still have to be competent to be able to deliver that and they still have to have the technical knowledge that enables them to deliver Fire Safety Engineering but, because the problem is simple, then that competency might be delegated to them. And the same thing happens in many places with the Fire Service that we end up delegating the role of the fire safety engineer to others and that sometimes creates a little bit of a confusion of who is responsible. But the reality is, technically speaking, it remains the Fire Safety Engineer who is responsible but, depending on the regulatory framework as Luke said, it can be delegated to others.

GURU MADHAVAN

Luke, let's talk about magic numbers. What are they, in relation to Fire Safety Engineering?

PROFESSOR LUKE BISBY

Okay, magic numbers, I mean, I suspect, Guru, that this question relates to a conversation that you and I had many years ago. One of the examples that I think I used with you back then was obviously the example of the two and a half minute, kind of, presumed safe evacuation time that gets used in a lot of contexts in Fire Safety Engineering, which finds its way back to the time that it apparently took to evacuate a very specific theatre subject to a very specific fire, actually, here in Edinburgh, where Jose and I are sitting. And it kind of became this number, this two and a half minute evacuation time, that many fire regulations around the world sort of got, I wouldn't say bound to, but kind of thought about within the context of that two and a half minutes. So, that's one example that's been written about and talked about quite a lot. So, maybe that's a less interesting one. The other one that I think I mentioned to you back then, was this idea that in London specifically there was, and this is sort of legend within the fire safety community, there was a rule, I don't think the rule exists anymore, that there was a certain dead end distance that you were allowed to have in a street that was a cul-de-sac. So, if you had a dead-end street between two buildings, that went in between two buildings, it was only allowed to go in so far, however many yards. And if it went in further than that, you had to have a turning circle at the end of it so that you could get a fire appliance, a fire truck, if you like, down that dead end street, turn it around and drive out forwards. You wouldn't have to drive out backwards. And if you looked back at where the specific distance had come from and you traced it back through the regulations over the decades and centuries or whatever, what you found the distance was the, and I'll try to get this right here, I think it was the maximum distance that it was judged you could humanely coax a horse backwards in whatever date. Right? So, I guess you could inhumanely coax a horse backwards if you wanted to. But they didn't want people to be inhumanely coaxing horses backwards out of dead-end lanes. So, they insisted that you have a turning circle at the end. Now, whether that is true or how true that is, I don't know. It's certainly an interesting story. But that's one example of, you know, you end up with maximum dead-end lane distances in the city of London where you have, you know, shining glass 50-story tower blocks, the footprints of which and the road layouts around which are dictated by, allegedly, the maximum distance you can humanely coax a horse backwards. And that one, you know, particularly sort of silly example. But, fire safety engineering, and I know it best because it's the discipline that I work within but I suspect all engineering disciplines, have similarly strange historical magic numbers that underpin many of the decisions that are made and that many people who practice in those disciplines don't really know or think about or understand why they're making the choices that they make. My colleague Angus Law has this wonderful expression: “We make the regulations. We the engineers, we make the regulations, and we make the codes. And thereafter they make us.” And I think that's a brilliant quote.

PROFESSOR JOSE TORERO CULLEN

I think the context of Fire Safety Engineering is a very unusual one. And it relates very much to, you know, innovation and changes that we introduce in our society. The reality is that Fire Safety Engineers don't create our problems. The problems get created for us. So, in essence, what happens is that as we've been innovating in any aspect of our sort of regular lives, new problems get created for us. And as those new problems get created for us, you know, then we have to respond and many times the way in which we respond is not necessarily based on full technical knowledge, but there is a lot of intuition and sometimes just purely observations and unfortunately, many times, as you say, even superstition because we have to respond to problems that we really do not know how to solve. So, you know, we've been talking about regulating, for example, the compostability of materials before we even understood fluid mechanics, heat transfer or combustion. So, we didn't understand any of the underpinning physics behind those problems. Nevertheless, we still needed to make buildings in which fires behaved appropriately. So, what we tended to do through centuries is to come up with solutions that were based on some sort of experiential knowledge. And that experiential knowledge translated itself into these magic numbers. And Margaret Law represents one of the most significant individuals in the profession because I was in the room when she delivered, you know, this famous paper, Golden Rules and Magic Numbers. And basically she was one of the first individuals who managed to actually harness an enormous amount of knowledge that got generated in the 1950s and 1960s, you know, and convert that into answers to all these magic numbers. You know, what she basically did was try to explain them and, whenever they could not be explained, she actually showed what the limitations of these magic numbers and these golden rules were. Giving sort of technical credibility to the way in which we regulated and the way in which we did things. So, in essence, I mean, she is the first true Fire Engineer because she's the first one to really use technical knowledge in support of decision making. And for the first time, in the period of Margaret Law, we found ourselves in a position in which we actually caught up with the problems that were being generated for us. Now, after that, we probably have lost a little bit of control over the situation and innovation has moved way too fast and we're falling behind again. And we are once again creating magic numbers and golden rules, you know, to try to respond to questions that we really, truly do not have answers. And, you know, examples of that are lithium-ion batteries, you know, tall timber buildings, photovoltaics in walls and roof spaces. You know, all these new technologies that are being pushed at an extraordinary speed are forcing us once again, you know, to start answering those questions with things that are potentially not fully based on technical knowledge.

GURU MADHAVAN

Luke and Jose, for a final question for this conversation. What do you think based on your research experience, professional experience… the future of Fire Safety Engineering, as you see from this point?

PROFESSOR JOSE TORERO CULLEN

I mean, I think that the one thing that we have to recognize is the world of technology, the world of knowledge is evolving extraordinarily fast. And the future of fire safety is very, very, very clear. We have to move away from static regulations. We have to move away from this sort of confusion of competency that we have in this space into a space in which we make the professionals responsible for the design. So, in essence, we have to start regulating people. You know, we have to start making sure that those who are exercising the profession of Fire Engineers or Fire Safety Engineers are competent enough to be able to deal with these challenges. We don't have time to change regulations constantly. So, what we need to do is guarantee that we have competent people doing the job. This is something that we've struggled enormously through decades or centuries of existence of Fire Safety Engineers. It’s that we don't manage to professionalize the discipline to the point that we can fully rely on the competency of those delivering fire safety. There's too much confusion of competency and we need to move away from that.

PROFESSOR LUKE BISBY

Then we need, I think, to shift from the situation where we regulate the artifacts of the engineering work to regulating the engineers themselves. And what that means is that we have a bit of a chicken and egg problem because, you know, I could argue that we need Fire Safety Engineers across the industry to be much more competent and therefore we need to educate large numbers of Fire Safety Engineering graduates from programs like the one I operate. You could absolutely accuse me of being self-interested in that, as someone who runs a program, but I don't want to generate those people unless there is a vibrant, interesting, transforming industry to send them out into. To do that would be to send people out into a world that doesn't need their skills and I'm not interested in doing that. But, if the world changes and those people aren't there to deliver the necessary skills, then we get into a situation where, you know, we just can't deliver on that change in approach because we don't have enough competent people. So, we find ourselves in a chicken and egg problem. And so what we need to ask ourselves is how much do we care about fire safety in the built environment? How much do we value it, potentially, over and above other things? And then we have to be honest about our delivery of that value. And so if we value Fire Safety Engineering in the built environment, if we really mean it, then we are going to have to devote public resources to educating the people and we're going to have to change the way that we regulate the profession and start regulating individuals.

GURU MADHAVAN

The history of fire safety made me realize two things. First, in engineering, problems can occasionally be solved by superstition as in the duration of the British national anthem informing international evacuation rules. Second, absolute safety doesn't exist and safety judgements aren't always objective. It comes down to how safe is safe enough. Even, how fair is safe enough? That's why Fire Safety Engineering necessarily involves a blend of technology, psychology, sociology, and maybe a little bit of magic.

Thanks for listening to Create the Future, a podcast from the Queen Elizabeth Prize for Engineering and Peanut and Crumb. Look out for new episodes every two weeks and tell your friends and follow QEPrize on social channels: Instagram, Facebook and X, formerly Twitter. This show was produced by Tess Davidson. And, until next time, this is your host Guru Madhavan.