July 2, 2025

208 - The basics of fire water supply with Szymon Kokot

208 - The basics of fire water supply with Szymon Kokot
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208 - The basics of fire water supply with Szymon Kokot
208 - The basics of fire water supply with Szymon Kokot
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Water might seem like the simplest part of firefighting – just point and spray, right? Well, as you can imagine, the reality is a bit more complex. In this conversation with veteran firefighter and CFBT instructor Szymon Kokot, we pull back the curtain on firefighting's most critical resource to reveal the intricate science and logistics behind effective fire suppression.

Did you know a standard fire truck carries just 10 minutes' worth of water for a typical residential fire? Or that a water-filled fire hose can weigh up to 45 kilograms per 20-meter section? These physical realities shape every aspect of firefighting operations and explain why building water supply systems are absolutely vital for effective emergency response.

Szymon walks us through essential concepts that every fire engineer should understand – from critical flow rates (2 liters per minute per square meter of fire area) to tactical flow rates (4 liters per minute per square meter) that provide both effectiveness and safety margin. We explore how water's cooling capacity works primarily during evaporation, why cooling burning materials is more important than extinguishing visible flames, and how different water application techniques serve different tactical purposes.

The conversation demystifies hydrants versus standpipes, dry versus wet systems, and the specialised requirements for different building types – especially the unique challenges of high-rise structures where external water supply is virtually impossible. We also confront the all-too-common reliability issues that plague these systems, from maintenance problems to vandalism.

Whether you're a fire engineer looking to design more effective systems, a firefighter interested in the science behind your craft, or simply curious about this intersection of physics, engineering and emergency operations, this episode delivers valuable insights into how water – our oldest firefighting tool – continues to shape modern fire safety design and operations.

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The Fire Science Show is produced by the Fire Science Media in collaboration with OFR Consultants. Thank you to the podcast sponsor for their continuous support towards our mission.

00:00 - Introduction to Water Supply Discussion

08:36 - Physics of Water in Firefighting

17:06 - Flow Rates and Critical Water Needs

28:22 - Building Hydrants and Supply Systems

42:11 - Dry vs Wet Pipe Systems

48:27 - Fire Engineering and Firefighter Collaboration

54:41 - Closing Thoughts on Water Supply

WEBVTT

00:00:00.542 --> 00:00:02.448
Hello everybody, welcome to the Fire Science Show.

00:00:02.979 --> 00:00:17.750
When I told you before that if you want to know what firefighters want from your fire engineering and how can you support firefighters and their operations with your fire engineering, the best way is to ask a firefighter.

00:00:17.750 --> 00:00:20.106
And that's what I'm trying to do today.

00:00:20.106 --> 00:00:25.789
In this episode I have invited once again my firefighting friend, shimon Kokot.

00:00:25.789 --> 00:00:40.701
Shimon is a local or perhaps even a global legend of combatant fire behavior training and he is my go-to person to consult the matters of the interface between fire safety engineering and firefighting.

00:00:40.701 --> 00:00:49.548
And when I was thinking about the topics or questions that I could ask the Shimon, one was very obvious to me and that is the water supply.

00:00:49.548 --> 00:00:59.841
I had privilege to learn a lot about the water supply because I was doing my master's at a fire academy where we learned it alongside the firefighters.

00:00:59.841 --> 00:01:04.731
So actually I had enough luck to learn this as a firefighter would.

00:01:04.731 --> 00:01:17.090
But I have a feeling a lot of us fire safety engineers do not have in-depth understanding of how water supply works in case of a fire, how impactful it is for firefighting.

00:01:17.090 --> 00:01:28.123
It's obvious it's impactful, but exactly how does it work and how we as fire engineers can support our firefighting colleagues by designing better water supply systems for the buildings.

00:01:28.123 --> 00:01:38.253
So in this podcast episode, water Supply 101 with firefighting instructor Szymon Kokot, let's spin the intro and jump into the episode.

00:01:42.760 --> 00:01:44.364
Welcome to the Firesize Show.

00:01:44.364 --> 00:01:47.813
My name is Wojciech Wigrzyński and I will be your host.

00:01:47.813 --> 00:02:17.352
The Firesize Show is into its third year of continued support from its sponsor, ofar Consultants, who are an independent, multi-award-winning fire engineering consultancy with a reputation for delivering innovative, safety-driven solutions.

00:02:17.352 --> 00:02:31.051
As the UK-leading independent fire risk consultancy, ofar's globally established team have developed a reputation for pre-eminent fire engineering expertise, with colleagues working across the world to help protect people, property and the planet.

00:02:31.051 --> 00:02:47.191
Established in the UK in 2016 as a startup business by two highly experienced fire engineering consultants, the business continues to grow at a phenomenal rate, with offices across the country in eight locations, from Edinburgh to Bath, and plans for future expansions.

00:02:47.191 --> 00:02:55.433
If you're keen to find out more or join OFR Consultants during this exciting period of growth, visit their website at ofrconsultantscom.

00:02:56.721 --> 00:02:57.846
And now back to the episode.

00:02:57.846 --> 00:03:00.146
Hello everybody, welcome to the Fire Science Show.

00:03:00.146 --> 00:03:04.129
I am joined today by my good friend, szymon Kokot.

00:03:04.129 --> 00:03:06.967
Hey Szymon, hi Wojciech and hello everyone.

00:03:06.967 --> 00:03:14.671
Good to have you back in the podcast and very glad that you took my invite for this non-trivial episode.

00:03:14.671 --> 00:03:28.408
The reason I brought you here some weeks ago I recorded a podcast episode about fire safety engineering with firefighters in mind, and, of course, the first thing I said in that episode if you want to know what firefighters want, talk to them.

00:03:28.408 --> 00:03:32.106
Therefore, here we are you are my firefighter of choice.

00:03:32.106 --> 00:03:48.008
But the second thing was I was contemplating what is something that could be very important to firefighters that we fire engineers do not really appreciate or have not had a chance to really learn, and then it struck me that it could be water.

00:03:48.340 --> 00:03:59.866
So let's have a wet episode of Fire Science Show and I hope you will tell me all the interesting stuff about how you use water, why you need water and how it works in firefighting.

00:03:59.866 --> 00:04:02.747
I'll try to do my best, of course.

00:04:02.747 --> 00:04:06.915
Yeah, so what are you using water for in the firefighting?

00:04:06.956 --> 00:04:07.157
job.

00:04:07.157 --> 00:04:11.570
Yeah, so Physics 101, I guess everybody knows.

00:04:11.570 --> 00:04:18.666
I assume that everybody listening to your show should know that if we use water, we use it for cooling.

00:04:18.666 --> 00:04:21.649
A fire is a phenomenon that produces heat.

00:04:21.649 --> 00:04:30.711
Therefore, one way of combating it is to cool it down below a certain point in which the fire propagation is no longer possible.

00:04:30.711 --> 00:04:34.680
So we of course, use the cooling capacity of water.

00:04:34.680 --> 00:04:45.767
Now, as firefighters fire engineers, educated firefighters we know that water takes the most, the biggest amount of heat when it evaporates.

00:04:45.767 --> 00:05:13.005
So we will try to use water in a way so that it turns into steam and by using the characteristic called the latent heat of evaporation or phase change, we take probably six times as much heat as it is necessary for the water to be heated from the average 15 or 18 degrees to 100 when it evaporates.

00:05:13.005 --> 00:05:16.252
So yeah, so that will be our main goal.

00:05:16.252 --> 00:05:20.845
To use water is to cool down to extinguish.

00:05:20.845 --> 00:05:33.004
Then, when we produce steam, we also dilute the oxygen and therefore it's another joint mechanism of extinguishing.

00:05:33.906 --> 00:05:34.708
By cooling?

00:05:34.708 --> 00:05:39.694
Is it primarily cooling the hot gases products or?

00:05:53.910 --> 00:06:00.574
you care also about cooling the structure itself, like the walls and other elements work.

00:06:00.673 --> 00:06:24.973
That was for me very instrumental in understanding that we may combat the gases which are the effect of the phenomena that are occurring inside the compartment, but it's because of the heat stored in the solids by conduction is why these solids are thermally decomposing and producing gases.

00:06:25.033 --> 00:06:39.447
Therefore, the larger part we say like the two-thirds of the cooling capacities is actually necessary in the fuels to extract the heat from them and stop producing flammable gases.

00:06:39.447 --> 00:06:46.591
And therefore, by understanding this, of course, we will combat any threat from the flammability of gases.

00:06:46.591 --> 00:07:06.935
When we travel to the seat of the fire, when we dive into the smoke, we want to cool and dilute the atmosphere so that we have a safe journey, let's say, so that we cool the gases so they don't ignite but also they don't carry the heat behind our back, to heat the fuel behind our backs.

00:07:06.935 --> 00:07:13.653
And by doing this we limit the possibility of having, let's say, an escape route cut off.

00:07:13.653 --> 00:07:27.767
But the goal is to travel to the seat of the fire and put the water on the burning fuel so that it stops producing smoke but also heat, because it's a self-propelling mechanism, as everybody probably is well aware of.

00:07:28.420 --> 00:07:35.189
So if you had a fully developed fire, a flash-over fire, you come in, you spray, disperse water spray.

00:07:35.189 --> 00:07:45.050
I guess it's, let's say, easy I'm not sure you can call it easy, but easy to put down the flames down, but if you stop applying water at that point, it all evaporates.

00:07:45.050 --> 00:07:49.959
You did not, you did not take away the heat from the structure yeah, so it may just well reignite very soon.

00:07:49.978 --> 00:07:51.122
Yeah it's it's.

00:07:51.122 --> 00:08:00.925
There's a couple of mechanisms combined here, but first of all we always teach because I'm also an instructor for cfbt compartment, fire behavior training.

00:08:00.925 --> 00:08:12.170
We teach that gas cooling, as it is originally called by the Swedes and then applied globally, gas cooling is not an extinguishing technique.

00:08:12.170 --> 00:08:18.574
It's a technique to secure your passage to a place where you can effectively extinguish.

00:08:18.574 --> 00:08:23.228
So it has a specific goal, it has a specific way of application and so on.

00:08:23.870 --> 00:08:52.351
We will rather normally in European countries where we use sprays because we need to conserve water more and we are, generally speaking I hope nobody will be offended by this but generally speaking we are less aggressive in our approach to interior firefighting compared to our American colleagues who use a smooth board which don't have such possibility to disperse water into fog.

00:08:53.520 --> 00:09:05.712
There is a possibility, of course, by halfway opening of the bale or rapid movements in the inverted U or O pattern and so on, to create some droplets.

00:09:05.712 --> 00:09:10.152
They will rather focus on cooling different surfaces and producing steam.

00:09:10.152 --> 00:09:30.190
There isn't a lot of steam produced in this way, but when we use sprays we rather avoid applying water to the structure, especially the ceiling, because of the amount of heat generated will turn everything into steam and if we don't cool the gases, the gases will not contract.

00:09:30.190 --> 00:09:36.423
If we evaporate the water on the ceiling, it will produce steam but will not contract the gases.

00:09:36.423 --> 00:09:45.210
Still, in 100 degrees Celsius, water turns into steam in the ratio of 1 to 1 to 1700.

00:09:45.210 --> 00:09:50.900
In 200 degrees is 1 to 2100 or 2600, and so on and so on.

00:09:50.900 --> 00:09:54.931
It just according to Clapeyron's rule.

00:09:54.931 --> 00:10:02.866
The same amount of water will produce more volume of steam if it's heated to a larger temperature yeah.

00:10:02.947 --> 00:10:09.284
Yeah, so we must avoid what we call the water trap or the steam trap With this method of application.

00:10:09.284 --> 00:10:12.020
This is a concern, so yeah.

00:10:12.020 --> 00:10:22.731
So then we travel and then when we see, or maybe have an idea that this might be the room of origin, well, normally we can't see anything.

00:10:22.731 --> 00:10:29.788
But let's say, we use the thermal imaging camera and we see that there's a piece of furniture burning in the corner.

00:10:29.788 --> 00:10:42.345
So we switch to our solid stream, we make use of the reach of the stream and we direct water to the seat of the fire and then therefore stop production of heat fantastic.

00:10:42.365 --> 00:10:56.609
So we're just a few minutes into the podcast, but I've already learned something new and I think a lot of listeners already learned something new that there is way, way more science into spraying water on stuff than you would think after watching a few of Hollywood movies.

00:10:56.609 --> 00:11:07.384
Okay, this is brilliant because there's a lot of choices and, of course, this means having a quick access to water is something that's absolutely critical for you.

00:11:07.384 --> 00:11:15.697
Um, another question, and I I guess this goes also back to to paul greenwood's research how much water do you actually need to to take down the fire?

00:11:16.139 --> 00:11:23.009
yeah, well, it depends, as professor spenson often says, but you know you can never answer.

00:11:23.009 --> 00:11:27.600
It depends, and be happy with yourself, because then you have to expect.

00:11:27.600 --> 00:11:28.222
I mean come on.

00:11:28.423 --> 00:11:34.601
Yeah, five buckets is not enough, and uh, and an air tanker is probably too much so.

00:11:35.243 --> 00:11:45.187
look, we approach firefighting just like, I guess, the engineering world in a in a manner that takes into consideration the factor of time.

00:11:45.187 --> 00:11:55.309
Yeah, because if the heat is produced over time, so joules over seconds, giving us watts, we also apply water over time.

00:11:55.309 --> 00:12:03.373
Therefore, when we say about flow rate, we say, let's say, 100 liters per minute, or gallons, or whatever.

00:12:03.679 --> 00:12:07.346
We say liters in this podcast, please, Okay, yeah, okay, I will.

00:12:07.466 --> 00:12:11.062
I will, but I already gave praise to the American firefighters.

00:12:11.062 --> 00:12:13.323
They do fight more aggressively.

00:12:13.323 --> 00:12:24.981
Perhaps that's why they have to use gallons instead of liters, that's also true, but they have more lightweight constructions, they have bigger roads, bigger trucks, and it's just another reality.

00:12:24.981 --> 00:12:25.822
So we don, and it's just another reality.

00:12:25.822 --> 00:12:28.269
So, we don't really want to compare anything.

00:12:29.059 --> 00:12:32.229
Yeah, but Prince was trying to say which is better or worse.

00:12:32.229 --> 00:12:32.811
No, no, of course not.

00:12:33.421 --> 00:12:34.181
But okay.

00:12:34.181 --> 00:12:36.264
So the late Paul Greenwood.

00:12:36.264 --> 00:12:45.113
In his early work, I guess around 90s I think his book Fog Attack was published in 1990 or 91.

00:12:45.113 --> 00:12:53.629
He referred to something that was called critical, tactical and optimal flow rates.

00:12:53.629 --> 00:12:57.277
This applies to residential areas.

00:12:57.277 --> 00:13:11.015
We differentiate this from industrial area basically because of the fact of the height of the ceiling and normally larger floor plans, resulting in a bigger volume.

00:13:11.015 --> 00:13:26.033
Therefore, in a bigger volume, the dynamics of the development of fire may differ from the smaller room, as you probably mentioned already a couple hundred times in your over 200 episodes.

00:13:26.779 --> 00:13:31.392
When there's a flashover it's like a game over for this compartment.

00:13:31.392 --> 00:13:35.191
But not every compartment has the ability to flashover.

00:13:35.191 --> 00:13:43.410
Basically, first of all because of the geometrical aspects and secondly, if there's not enough air it will suffocate.

00:13:43.410 --> 00:13:49.503
If there's not enough air, it will suffocate.

00:13:49.503 --> 00:13:59.107
So for residential, we can say that there is probably a limit or a spectrum of limit of the heat release rate, peak heat release rate that can be achieved by this particular compartment.

00:13:59.107 --> 00:14:06.480
Let's say we are now in a room that has, like what, four by three meters and probably two and a half to the ceiling.

00:14:06.480 --> 00:14:15.842
So you know as much as you can put stuff here, the the size of this door will will dictate the the piece release rate.

00:14:15.842 --> 00:14:19.431
So let's say it will be like let's give it four.

00:14:19.431 --> 00:14:20.312
Yeah, let's ask.

00:14:20.312 --> 00:14:22.884
I was gonna say let's give it a good six or seven.

00:14:22.884 --> 00:14:24.426
Yeah, it's also possible.

00:14:24.866 --> 00:14:38.914
Well, normally, if you calculate the number of the amount of heat you can take away, if you use one liter of water, it will be enough to combat, I think, 2.5 or 3 joules.

00:14:38.914 --> 00:14:48.772
If you apply this over a second, then you will use kilojoules, no megajoules, megajoules, of course, of course.

00:14:48.772 --> 00:14:56.980
Yeah, yeah, thank you for correcting me, but you can almost never use one liter of water perfectly.

00:14:56.980 --> 00:15:19.004
So this was actually the work that Paul Greenwood did in his doctoral thesis, where he applied different factors to understanding one word used in a British legislation which is adequate, what is adequate water supply?

00:15:19.004 --> 00:15:32.268
And it's interesting how one word can mean a vast reality of knowledge which is sufficient to write a doctorate and probably not even one doctorate.

00:15:32.750 --> 00:15:37.731
And the revolution yeah exactly, and so he came up with different formulas.

00:15:37.731 --> 00:15:50.687
But starting with his earlier formulas, let's say if we have what will be easy to calculate a 50 square meter flat that is fully developed fire.

00:15:50.687 --> 00:15:52.903
So there's fire everywhere.

00:15:52.903 --> 00:16:05.649
Every square meter is on fire and the flames are shooting out of every window, so there's enough surface for exchange of gases hot gas going out, well ventilated.

00:16:05.668 --> 00:16:07.113
It's Well-ventilated yeah.

00:16:07.779 --> 00:16:15.678
It's still under-ventilated in a way, because this fire could consume more air, just if it had the possibility.

00:16:15.678 --> 00:16:20.511
But by this let's say it's 50 meters of fully developed fire.

00:16:20.511 --> 00:16:31.245
If we apply two liters per minute per square meter we can probably start to be effective against combating this fire.

00:16:31.245 --> 00:16:37.520
So two liters per minute times 50 meters is 100 liters per minute.

00:16:37.520 --> 00:16:57.041
It's not a lot in firefighting reality, but we must take into consideration that this is a compartmentalized area, so we cannot apply with one nozzle this 100 liters to every you know square meter of this area.

00:16:57.581 --> 00:17:00.986
So there comes different factors into play.

00:17:00.986 --> 00:17:23.094
If, for the same fire, we apply 4 liters per minute, that gives us the result of a necessary flow rate of 200 liters per minute, we will have a tactical flow rate, which means that we will be already well protected and have good efficiency of extinguishing.

00:17:23.134 --> 00:17:27.309
So kind of what is necessary, plus all the margins of safety that you would apply yeah, yeah.

00:17:27.309 --> 00:17:30.949
Allowing you to be less efficient in the application, perhaps.

00:17:30.949 --> 00:17:31.470
Yeah, yeah yeah.

00:17:32.481 --> 00:17:36.875
Then he said something like 1.86, if I remember correctly.

00:17:36.875 --> 00:17:39.522
Therefore, for easier calculation, two liters per minute.

00:17:39.522 --> 00:17:50.508
You cannot go below that and hope that you will be effective below that and hope that you will be effective.

00:17:50.508 --> 00:17:56.044
If you aim at four, then you are both effective and have good protection for your firefighter, because then you have to put a human being inside or close to it.

00:17:56.044 --> 00:17:57.248
Then it's not fun.

00:17:58.281 --> 00:17:59.226
But this is for residential.

00:17:59.226 --> 00:18:01.423
For residential, yes, for residential.

00:18:01.423 --> 00:18:20.991
But then if you move to six, so that gives you 300 liters per minute, then there is no more gain in efficiency, but then you'll start losing water and it will be turned into water damage rather than efficiency of extinguishing.

00:18:20.991 --> 00:18:24.886
And then it's a simple formula.

00:18:24.886 --> 00:18:38.025
Now, if you take five as a factor, which is between four and six, that gives you easy calculation, because whatever is your area, you divide it by two and you add one zero.

00:18:38.025 --> 00:18:40.930
It's a very simple way of calculating.

00:18:40.930 --> 00:18:48.626
But then let's say, if you want to extinguish a residential fire, you don't have to really go into all these calculations.

00:18:48.626 --> 00:19:10.729
You can be based on your experience and also keep in mind that you have a 500 liters per minute nozzle, so that should give you a decent 250 square meters of area fully engulfed that you should be able to extinguish with this, provided that you can apply water perfectly.

00:19:12.021 --> 00:19:15.711
So that's one stream of water could be 500 liters per minute.

00:19:16.741 --> 00:19:22.371
Yes, or four or five, depending, but normally the nozzles apply this kind of flow rate.

00:19:22.371 --> 00:19:37.113
But then, okay, first of all you're not able to apply this to the whole surface, so you have to give more nozzles, and more nozzles means more time of preparing, more equipment, more people.

00:19:37.113 --> 00:19:49.126
Then, if there isn't discipline and there isn't knowledge in your team, everybody will turn to full power and then after four minutes you're empty with one tanker.

00:19:49.126 --> 00:19:51.592
Now comes into play your water source.

00:19:51.592 --> 00:19:53.000
Water supply, you know.

00:19:53.000 --> 00:20:09.551
But here you can see how very important and crucial is education, because they will not achieve more efficiency by standing in this one place and giving your full power inside, let's say, through a window, or maybe they are trying to already approach the door or whatever.

00:20:09.551 --> 00:20:15.732
So there's this whole education and then tactical game that you have to play.

00:20:16.900 --> 00:20:18.404
In terms of the timeframes.

00:20:18.404 --> 00:20:21.011
How long does it take?

00:20:21.011 --> 00:20:23.426
How long does the structural cooling take?

00:20:23.426 --> 00:20:23.888
Actually?

00:20:23.888 --> 00:20:25.442
Like do you plan this for?

00:20:25.442 --> 00:20:25.824
I don't know?

00:20:25.824 --> 00:20:28.832
Five minutes for an hour, for more than an hour?

00:20:28.832 --> 00:20:34.695
I assume you also probably would reduce the amount of water you use for the cooling phase the cooling of the structure.

00:20:34.695 --> 00:20:42.833
Yeah, yeah, yeah, you mean like the… you came in, you took the flaming combustion out, but your structure is superheated.

00:20:42.833 --> 00:20:48.503
So let's say this 50 square meter room, but do you mean combustibles or construction elements.

00:20:48.703 --> 00:20:50.945
Well, I guess you have to cool all of them.

00:20:50.945 --> 00:20:56.029
Yeah, but some of them with water, so you don't have the re-ignition.

00:20:56.029 --> 00:21:01.394
But if you have heat in your concrete walls, you just open the windows and let it cool down.

00:21:01.453 --> 00:21:05.957
It's not a threat, okay, okay, so for combustibles, I guess, how long would it take?

00:21:11.132 --> 00:21:12.236
So in that case, not that very long.

00:21:12.236 --> 00:21:20.788
No, no, I mean as long as it first of all releases gases, which means that it has, on average, more than 200 degrees Celsius of temperature.

00:21:20.788 --> 00:21:25.566
Then it continues to produce steam, so it's over 100.

00:21:25.566 --> 00:21:32.990
But if it's over 100 and it produces steam, theoretically you don't have really a good way of stating this.

00:21:32.990 --> 00:21:37.779
So as long as you can see some vapor, you continue to fight the problem.

00:21:37.779 --> 00:21:43.034
But from some moment it's not pyrolysis anymore, it's just evaporation.

00:21:43.034 --> 00:21:50.865
It's not pyrolysis anymore, it's just evaporation, and there's over 100 degree Celsius difference between those two thresholds.

00:21:51.330 --> 00:21:58.449
Do you and your colleagues already have some expertise in applying those rules for full exposed timber compartments like mass timber?

00:21:59.872 --> 00:22:13.613
I don't have such experience, and it's still rare experience in many people because of the relatively low frequency of occurring of these structures and them catching fire.

00:22:14.221 --> 00:22:24.461
I mean it's another obvious thing for mass timber that is going to participate in the fire, so therefore your consideration does it burn or not is gone because all surfaces would burn.

00:22:24.501 --> 00:22:39.521
I mean, I mean, look from a perspective of a firefighter, is is something I don't really even want to think about yeah it's just like, uh, you know, lithium-ion batteries or any kinds of new technologies that you know it's, it's nice.

00:22:39.521 --> 00:22:44.368
I I don't get me wrong, I mean I'm, I'm also a human being.

00:22:44.368 --> 00:22:51.528
I have a cell phone that uses batteries, a laptop and uh, you know and and you would not mind, living in a nice timber house.

00:22:51.627 --> 00:22:57.491
Yeah, and the cool, how you care about the environments and so on, but I I always say I'm sorry.

00:22:57.491 --> 00:22:59.126
I'm very straightforward about this.

00:22:59.126 --> 00:23:07.684
Firefighters are the guinea pigs, the experimental rabbits of any industry that produces anything for the world.

00:23:07.684 --> 00:23:09.329
You know, because it's being pushed to the market.

00:23:09.329 --> 00:23:20.851
Then something goes wrong, then we intervene and we are mostly the first ones to find out systemically what the hell is wrong with this or the other technology.

00:23:21.119 --> 00:23:29.869
Okay, I don't want to debate too much to Mustin but, it was just a curiosity, and if I'm curious then there's definitely plenty of listeners who are curious about this as well.

00:23:29.869 --> 00:23:34.351
In K, let's change the environment from residential.

00:23:34.351 --> 00:23:51.603
Let's say you're fighting in a shopping mall, perhaps an industrial building, so much larger spaces perhaps is less chance that you'll have an, a flashover in the classical way of understanding flashover, but you may have also many, many hundreds of square meters burning at the same time.

00:23:52.483 --> 00:24:03.006
similar principles apply, like 200 liters per minute, per no no, normally it's way more and it's not and it's not increasing linearly.

00:24:03.006 --> 00:24:11.053
But you know, you just take another formula and kind of exponentially increase the amount of water you need to apply.

00:24:11.053 --> 00:24:14.342
Then you also change your methods of application.

00:24:14.342 --> 00:24:24.720
The thing is that in a residential fire, as we said, there's first of all some limit of the heat that can be generated.

00:24:24.720 --> 00:24:27.148
It's limited by the geometry.

00:24:27.148 --> 00:24:43.263
So probably by using walls, hiding behind the walls, getting away from a straight line of radiation and so on getting away from a straight line of radiation and so on, you can.

00:24:43.263 --> 00:24:56.732
You can try and sneak up on the fire and, you know, apply some water, like maybe bounce it from the ceiling, create this sprinkler effect, or bounce it off the door frame from 10 meters before you actually are at this place.

00:24:56.833 --> 00:24:57.594
I saw those tricks.

00:24:57.594 --> 00:24:58.496
They're ridiculous.

00:24:59.200 --> 00:25:08.566
And it's not so easy to be applied during a large fire, where you know normally large constructions are also more lightweight.

00:25:08.566 --> 00:25:28.261
Therefore they are prone to collapse, and there is a certain point which is a gut feeling really at the fire, that you don't commit firefighters inside anymore unless there's obvious signs of people you need to rescue, other than that you don't risk life of your firefighters for rescuing property.

00:25:28.763 --> 00:25:35.337
And car parks, like how much water you need to take down a car or multiple cars so, yeah, so like a car.

00:25:35.417 --> 00:25:40.548
Well, again, it depends on the car parks underground, or or?

00:25:40.769 --> 00:25:42.343
yeah, let's go half open.

00:25:42.343 --> 00:25:43.125
No, no, no.

00:25:43.125 --> 00:25:48.488
Well, let's make it difficult underground or very large open plan car parks, like airport car parks yeah, then you.

00:25:48.587 --> 00:25:53.603
Then you enter through a chimney, which is not the pleasure in itself, yeah, you know.

00:25:53.603 --> 00:25:59.691
But I'd say, look, there are majority of fires, as far as I know, in car parks.

00:25:59.691 --> 00:26:09.032
They end with a couple of cars being burned, but every now and then all the cars burn like hundreds or thousands of them.

00:26:09.032 --> 00:26:17.606
We heard about some cases in England, in Norway, I guess, or Sweden, I don't know one of these Scandinavian countries.

00:26:17.646 --> 00:26:18.529
Yeah, in Norway there was Stavanger Airport.

00:26:18.529 --> 00:26:19.594
Don't know one of these Scandinavian countries.

00:26:19.594 --> 00:26:20.557
Yeah, in Norway there was Stavanger airport.

00:26:20.577 --> 00:26:21.078
Yeah, near to the airport.

00:26:21.078 --> 00:26:36.089
Yeah, yeah, but we can also estimate the peak heat release rate and the time of fire for a single vehicle, and then it's probably compared to one compartment in the house.

00:26:36.089 --> 00:26:38.894
So, if you can really access this car.

00:26:38.894 --> 00:26:51.868
Well, extinguishing a car is easier, in a way that it burns inside the car, but what's burning it's your seats, it's your rubber, plastic, whatever's inside, unless it's a battery.

00:26:51.868 --> 00:26:55.909
But then it's another, a little bit of a different situation.

00:26:55.909 --> 00:27:00.030
But then if the battery burns, really what can you do?

00:27:00.030 --> 00:27:02.608
First of all, this car is already lost.

00:27:02.680 --> 00:27:05.329
You will not resell it, not even in Poland.

00:27:07.743 --> 00:27:09.729
Well, it sounds like a challenge.

00:27:09.729 --> 00:27:13.432
Yeah, I'm glad People are saying and they don't try that.

00:27:13.432 --> 00:27:15.480
Yeah, yeah, let's not give people ideas.

00:27:15.500 --> 00:27:15.942
Don't try that.

00:27:15.942 --> 00:27:36.019
Yeah, yeah, let's not give people ideas, but let's say I would say, you know, like, if you take what's the English term for this Hose reel, so like a 90 millimeter in Poland or 22 or 25 in different countries Rubber 60 meter long hose line with the Water attached to it.

00:27:36.442 --> 00:27:39.296
Yeah, with high pressure that you can apply.

00:27:39.296 --> 00:27:43.646
It's normally possible to extinguish one car with this.

00:27:43.646 --> 00:27:57.148
So sometimes it depends when you see or know there's still cameras working maybe or something and you see it's one car, or you see it just by arriving and you understand it's one car, then well, well, whatever works.

00:27:57.148 --> 00:28:00.154
If it's more cars, then it's problematic.

00:28:00.154 --> 00:28:10.586
What is problematic is really the obscured vision, the heat you need to take into your body before you are able to understand where you are, what you are applying water at.

00:28:10.605 --> 00:28:15.290
So again, so in the end we're all again in the region of hundreds of liters per minute.

00:28:15.351 --> 00:28:17.205
Yeah, and you probably can work with that.

00:28:18.221 --> 00:28:28.269
I really wanted to understand the numbers of how much water actually you would need and you come in big red fire trucks.

00:28:28.269 --> 00:28:29.652
They have their own water supply.

00:28:29.652 --> 00:28:32.387
That's usually a few cubic meters of water, right.

00:28:32.709 --> 00:28:32.970
Yeah.

00:28:33.140 --> 00:28:35.182
So at like 200 liters per minute.

00:28:35.202 --> 00:28:42.914
So at like 200 liters per minute, 2,000 liters to two and a half is the, let's say, the most popular.

00:28:44.859 --> 00:28:49.250
It's what we call the medium vehicle, so at 200 liters that's 10 maybe minutes of extinguishing action right yes.

00:28:49.531 --> 00:28:54.251
Okay, so it's obviously you need water in the building that the building provides.

00:28:54.251 --> 00:29:04.048
And here comes the fire engineer, who is right about to design a building, and one of their duties is to design that water supply for firefighting.

00:29:04.048 --> 00:29:12.327
So perhaps let's talk about different ways of delivering water to the perimeter of the building and to the interior of the building.

00:29:12.327 --> 00:29:22.546
We call them hydrants, but what kind of the devices are used for that and how much water they actually can get I'm really curious about it.

00:29:23.166 --> 00:29:31.371
Let's say to some extent technicalities, but probably mainly about your experience, experiences in using those devices.

00:29:31.371 --> 00:29:32.874
Because it's easy.

00:29:32.874 --> 00:29:35.785
You know, to draw a line right is a pipe.

00:29:35.785 --> 00:29:41.442
Hundred mil five bars of pressure go, but in reality it verifies the drawing.

00:29:41.481 --> 00:29:42.463
Sometimes very different.

00:29:42.463 --> 00:29:53.957
Yeah Well, so I'll start by saying that I've been a firefighter for 25 years, so it's a way different story right now than it was 25 years ago.

00:29:53.957 --> 00:29:59.311
And also, what I can speak about from experience is Poland.

00:29:59.311 --> 00:30:20.471
But there's so many different countries that have so many different realities, and even you know things like we use a 52 millimeter hand line for interior attack, and the Spain will use 42 or 38, which is more maneuverable but has more pressure loss and applies less water.

00:30:20.471 --> 00:30:27.989
So probably they can go longer, but they cannot extinguish as efficiently as we do, unless we really waste water.

00:30:28.380 --> 00:30:30.627
So you know, variables can really kill you.

00:30:30.627 --> 00:30:33.346
But okay, in general.

00:30:33.346 --> 00:30:41.403
We have a code in Poland that says that there should be a liter per second or a liter and a half per second.

00:30:41.884 --> 00:30:44.307
Which translates to 60-90 liters per minute.

00:30:45.221 --> 00:30:45.542
Yeah.

00:30:45.923 --> 00:30:46.866
My math checks out.

00:30:46.866 --> 00:30:47.849
Yeah, yeah, I'm good.

00:30:49.042 --> 00:30:49.664
If I'm correct.

00:30:49.664 --> 00:30:50.848
Yes, Is that correct?

00:30:50.950 --> 00:30:51.873
I think yeah.

00:30:52.821 --> 00:30:54.689
Which is not really a lot of water.

00:30:55.781 --> 00:30:57.079
We're just talking about 200-400.

00:30:57.180 --> 00:30:58.547
Yeah, if you compare that.

00:30:59.721 --> 00:31:04.237
But this is per single line or overall to the building Per hydrant.

00:31:04.397 --> 00:31:04.878
Per hydrant.

00:31:04.878 --> 00:31:09.672
Okay, now, water cannot be squeezed and water cannot be stretched.

00:31:09.672 --> 00:31:12.378
It's almost as solid.

00:31:12.378 --> 00:31:27.768
So I'm saying this to say that if you have a building and it has an external hydrant well, it used to be the case that hydrants were just valves on the ground you have to first prepare the hydrant.

00:31:27.768 --> 00:31:36.075
So you have to take your hydrant I don't know stand or appliance from your truck, find the hole in the ground, open it.

00:31:36.075 --> 00:31:40.430
Sometimes it's, you know, rusty, or it's under grass, or whatever.

00:31:40.430 --> 00:31:41.412
It takes time.

00:31:41.412 --> 00:31:49.009
That's why we always say that as soon as we arrive on the scene, one team goes inside, the other team prepares water supply.

00:31:50.102 --> 00:31:53.645
You're sure that the truck will last a few minutes and after those few minutes.

00:31:53.645 --> 00:31:54.548
You want to have something.

00:31:54.548 --> 00:31:59.188
Exactly, exactly, and the hydrant is connected with the truck.

00:31:59.188 --> 00:32:00.551
I assume because the truck has the pump.

00:32:02.103 --> 00:32:04.550
Yeah, but the hydrant should have some pressure itself.

00:32:04.579 --> 00:32:07.690
Yeah, but it's not that you can put a hydrant directly to a nozzle and apply.

00:32:09.082 --> 00:32:10.888
Well, you could probably do that.

00:32:10.888 --> 00:32:13.669
There will be limited.

00:32:13.669 --> 00:32:36.290
I mean, if you are, let's say, uh, still uh urban area and have a grass fire, yeah, then you can probably find a hydrant and maybe just go if it's like within the reach, but but then yeah, the thing is that you can place your truck anywhere, but you cannot pull out the hydrant from the ground to make it closer to the fire.

00:32:36.994 --> 00:32:40.945
So you have to really be lucky to use this kind of scenario.

00:32:40.945 --> 00:32:43.711
So we opened the hydrant.

00:32:43.711 --> 00:32:46.084
Hopefully it works, hopefully there's nothing missing.

00:32:46.084 --> 00:32:57.146
It used to have aluminum valves, so they were stolen by the gentlemen that collect Collectors, collectors that sell them later.

00:32:57.146 --> 00:33:00.192
Now they are plastic, so there's less problem.

00:33:00.192 --> 00:33:06.936
Hopefully it was dehydrated, dewatered if it was used before winter.

00:33:06.936 --> 00:33:12.232
So nothing froze, nothing exploded underground and it's still operational.

00:33:12.232 --> 00:33:25.107
Actually, we as firefighters very often go to our protected area and simply check the hydrants If they're working and we have frequent updates about them Not in an action, but just outside of action.

00:33:26.363 --> 00:33:36.131
Yeah, just between them, and sometimes it's done by the firefighters from the fire station, but sometimes it's done by the prevention, by the prevention, but probably less and less.

00:33:36.131 --> 00:33:43.406
They have more and more work in buildings, in auditing buildings and making sure everything's okay.

00:33:44.931 --> 00:33:49.049
Yeah, and so you described the exterior perimeter hydrants.

00:33:49.049 --> 00:33:50.705
How about the interior of the buildings?

00:33:51.384 --> 00:33:56.549
So why I said about the water cannot be squeezed and cannot be stretched?

00:33:56.549 --> 00:34:10.989
Because there's some pressure in the hydrant network and if you take water from a hydrant by one outlet, one hydrant from the hydrant network then obviously the pressure will drop.

00:34:10.989 --> 00:34:24.992
If you want to have more water you can take another hydrant and another, but at some point you'll have not enough pressure, so that will turn into less flow rate yeah in.

00:34:24.992 --> 00:34:28.398
In certain circumstances it's all hydraulics.

00:34:28.398 --> 00:34:32.327
I won't go into it, but there there's a limit yeah, there used to be.

00:34:32.427 --> 00:34:39.599
there used to be, uh, less effectiveness, incorporating with the hydrant network management.

00:34:39.599 --> 00:34:42.971
Now it's a way better situation.

00:34:42.971 --> 00:35:00.704
I've been a deputy fire chief responsible for operational activity of the headquarters in Nijica and I was able to have frequent meetings with these guys and whenever we wanted to have pressure boosted by them, we just said that, boost the pressure, and so on.

00:35:00.704 --> 00:35:12.030
Sometimes they would tell you back in the days we cannot do this because somebody's toilet will shoot out Stuff, like that happened before the renovation of these networks.

00:35:13.221 --> 00:35:19.612
I mean we've seen in those wild and urban interface fires when large area.

00:35:19.612 --> 00:35:31.454
Wildfires approach the cities, how hydrogen networks can get overwhelmed, because I mean you design this network to secure you for a fire of a single building maybe two three buildings.

00:35:31.880 --> 00:35:43.327
But if there's a hundred buildings burning at the same time in the neighborhood and you want to get the water from all ends of the network, you eventually cap out the ability of that network to provide pressure.

00:35:43.327 --> 00:36:05.451
So I think many of us have seen recollections of firefighting in some of those wild and urban interface fires where you basically run out of the water and it's not that there was insufficient water, it's just that the flow rates at every single outlet of that system were compromised because too many outlets were open at the same time.

00:36:05.451 --> 00:36:18.659
I'm luring you into the building because the question is why do you even bother us engineers with designing an internal hydrogen network inside the building?

00:36:18.659 --> 00:36:24.811
How much that internal uh network of of water pipes really changes the battlefield?

00:36:24.811 --> 00:36:27.224
Yeah, for you, perhaps I you know what.

00:36:27.224 --> 00:36:28.969
I'll ask you a different question to start with.

00:36:28.969 --> 00:36:36.487
Yeah, how much does the 52 water hose stretched fully full of water wave like?

00:36:36.487 --> 00:36:39.192
What is the, the mass of that hose?

00:36:39.231 --> 00:36:45.387
because the water in it weighs 42 kilograms and itself weighs another two or three.

00:36:45.489 --> 00:36:51.161
So 45 ish per 25 meters per 20 meter, so you have like 200 meter line.

00:36:51.161 --> 00:36:51.442
You have?

00:36:51.442 --> 00:36:56.025
Yeah, you have like 200 times for 45 kilos.

00:36:56.125 --> 00:36:57.065
It's half a ton.

00:36:57.365 --> 00:36:58.065
Half a ton.

00:36:58.786 --> 00:37:12.976
Good luck pulling that behind you and moving with that, but you already also have 500 liters water in it from your pump, so that's a quarter of your water that you brought on wheels just to fill in the water.

00:37:20.059 --> 00:37:21.262
And now you can start extinguishing.

00:37:21.262 --> 00:37:23.065
But this 500 went to and this is the, the 52 which I.

00:37:23.065 --> 00:37:26.333
I've attended the brilliant polish main school fire service, the fire academy today.

00:37:26.333 --> 00:37:29.204
So you understand, that's your end hose.

00:37:29.204 --> 00:37:31.731
You should go with 75s yeah, from the truck.

00:37:31.771 --> 00:37:38.833
so that's how much like six, eight hundred eighty eighty eight think 88 kilos per section.

00:37:39.800 --> 00:37:42.449
Yeah, that's why you need water points inside the building.

00:37:43.882 --> 00:37:44.885
Yeah, that's one thing.

00:37:44.885 --> 00:37:50.280
And also, look, I mean there's a variety of systems.

00:37:50.280 --> 00:37:52.989
There's dry and wet pipes.

00:37:52.989 --> 00:37:57.351
Even dry pipes are useful, provided that they are maintained.

00:37:57.351 --> 00:38:01.550
The biggest problem is always that you always that somebody will throw trash inside.

00:38:01.550 --> 00:38:02.804
Can you define the?

00:38:02.864 --> 00:38:07.289
difference between dry and wet pipe, outside of the fact that one is dry and the other is wet.

00:38:08.260 --> 00:38:19.032
Well, there's already water in those wet ones, and sometimes this water comes from an internal water source with pumps.

00:38:20.302 --> 00:38:23.831
So at the end of the outlet you open it, there's already water in it like a tap in the kitchen.

00:38:24.521 --> 00:38:27.168
And you just take whatever hydrant is there.

00:38:27.168 --> 00:38:29.681
So basically you don't have to bring any of your equipment.

00:38:29.681 --> 00:38:33.992
You just enter and, from a certain point, take it and use it.

00:38:34.561 --> 00:38:35.603
And the dry system.

00:38:35.603 --> 00:38:39.614
Do you have to fill it with water on both ends, or it's just yeah?

00:38:39.673 --> 00:38:46.666
yeah, it's like you don't have to do your stretch inside the building.

00:38:46.666 --> 00:39:03.090
You just put water to the inlet by the entrance or whatever point normally by the main entrance and you push water inside and then by fixed pipes it arrives at a certain floor and then you open it and just continue from there.

00:39:03.090 --> 00:39:12.068
But you basically you conserve time and you conserve your energy because you don't have to carry so much equipment.

00:39:12.219 --> 00:39:13.927
So it's like pre-stretch hose in your building.

00:39:14.139 --> 00:39:15.505
Yeah, yeah, exactly that Okay.

00:39:15.505 --> 00:39:16.849
Exactly that.

00:39:17.159 --> 00:39:19.476
And the biggest challenge with them is maintenance.

00:39:19.476 --> 00:39:19.980
Yeah, yeah.

00:39:20.139 --> 00:39:24.552
We would like to think they work, but many, many cases they don't work.

00:39:24.552 --> 00:39:28.840
They're like couplings missing or valves missing.

00:39:28.840 --> 00:39:32.992
So you want to have water on the third floor but it's already leaking on the second floor.

00:39:32.992 --> 00:39:35.969
Somebody put trash candy paper inside.

00:39:35.969 --> 00:39:38.811
It's stuffing your nozzle, or somebody put trash candy paper.

00:39:38.811 --> 00:39:40.239
Inside it's stuffing your nozzle.

00:39:42.199 --> 00:39:49.570
Normally we should use a smooth board then, because it can shoot out any garbage that it takes into the nozzle, and so on, Of course, like if it's a wet pipe and there's a hole in it, you'll know.

00:39:49.570 --> 00:40:00.590
Another question is what kind of flows and pressures are present in those hydrogen networks inside the buildings?

00:40:01.539 --> 00:40:14.985
Oh, really, here I don't have a very good orientation, but from what I remember, those inside hydrants we don't speak about standpipes, but inside hydrants they should have, I think two bar pressure.

00:40:14.985 --> 00:40:15.465
They should have.

00:40:15.465 --> 00:40:17.728
I think two bar pressure.

00:40:17.728 --> 00:40:25.434
They are tested for two bar pressure and probably a liter or a liter and a half per second.

00:40:26.496 --> 00:40:28.760
Okay, and how?

00:40:28.780 --> 00:40:30.708
about space, then it's for the incipient stage.

00:40:30.708 --> 00:40:36.170
So that should be more than enough If there's somebody that will actually take the hose and extinguish it.

00:40:36.170 --> 00:40:38.623
It's like you take this.

00:40:38.824 --> 00:41:10.204
It's like you have eight garden hoses for a bonfire you just you can do whatever you want with this comparison, which which translates into 30 showers overkill yeah basically, or 100 buckets, yeah, and buckets, 100 buckets, I love it and how many of those you would need, or how often would you like them to be in the building to make sense, like every third floor, every floor, every 50 meters, every half a kilometer?

00:41:10.204 --> 00:41:10.686
I don't know.

00:41:12.161 --> 00:41:20.630
Well, these are governed by prevention laws, the fight prevention and I'm not really well versed on these.

00:41:20.630 --> 00:41:30.813
I haven't been engaged in this, I was an operational firefighter, but from what I know well, basically we have to differentiate.

00:41:30.813 --> 00:41:35.251
These are for the public, to have an immediate action.

00:41:35.251 --> 00:41:38.449
Well then they can be used by a firefighter.

00:41:38.449 --> 00:41:46.925
If a firefighter knows there's a hydrant inside and the commander assesses okay, there's a good chance you can access this point and use the hydrant.

00:41:46.925 --> 00:41:54.748
So maybe you go now while we prepare backup, while these guys are stretching and preparing, another attack team is entering.

00:41:54.748 --> 00:41:56.246
You may go and try to see.

00:41:56.246 --> 00:42:06.983
It's a different story with uh, with uh standpipes, because standpipes you don't count on what's there, but standpipes, if they have a, be there wet.

00:42:06.983 --> 00:42:11.112
If they're wet, then then your pump can be used from the building.

00:42:11.112 --> 00:42:13.123
Then you have to have some operational knowledge.

00:42:13.123 --> 00:42:15.250
It's not like you go and there you know nothing.

00:42:15.250 --> 00:42:16.961
You should be there before the fire.

00:42:16.961 --> 00:42:17.603
You know.

00:42:17.623 --> 00:42:21.152
Can you please explain the difference between the hydrant and standpipe?

00:42:21.152 --> 00:42:24.730
It may be ridiculous for you, but for engineers it's not.

00:42:26.081 --> 00:42:37.887
Well, I would rather expect that it's for firefighters because, maybe it's not so obvious, so I'm hoping I'm not making a fool out of myself and the whole world is listening.

00:42:38.061 --> 00:42:39.320
The whole world is your time, simon.

00:42:39.320 --> 00:42:41.414
Tell me what is the finest stand.

00:42:45.804 --> 00:42:46.684
Well, a standpipe for me.

00:42:46.684 --> 00:42:57.536
In my understanding, a standpipe is a system of pipes fixed to a building that serves the purpose of extinguishing a fire by firefighters.

00:42:57.719 --> 00:42:59.224
So it's not that the public can access it.

00:42:59.224 --> 00:43:10.141
You have to have the special hose you have to have a special key to it special key to it.

00:43:10.161 --> 00:43:11.606
Yeah, I mean I have no idea how it works in different countries.

00:43:11.606 --> 00:43:15.135
I mean there could I I envisage the possibility that it's used by the general public, you know.

00:43:15.135 --> 00:43:24.141
But I would imagine that the capacity, extinguishing capacities of these are comparable to firefighting extinguishing capacities.

00:43:24.141 --> 00:43:36.347
Therefore, it may be too much for a regular person who's not ready, let's say, to have a nozzle that gives six bar of pressure and with the resulting reaction force.

00:43:36.387 --> 00:43:42.387
You know Newton's law action and reaction firefighter knows he should be he or she.

00:43:42.387 --> 00:43:44.244
They should be down on their knees.

00:43:44.244 --> 00:43:52.539
You know maneuvering their hips, you know kind of a sexy dance, rock and roll, but not to get knocked over by the opening of the nozzle.

00:43:52.840 --> 00:44:02.688
I think a lot of people are very, very surprised the first time they feel the force of a full firefighter's equipment Like it's way more than eight garden hoses.

00:44:03.059 --> 00:44:04.987
Yeah, it's definitely way more.

00:44:05.168 --> 00:44:16.112
Yeah, and the hydrons would be something accessible to public and sometimes they would also have like a hose on them, a hose with some sort of device at the end, nozzle at the end.

00:44:16.300 --> 00:44:25.101
It's either like a flat lay, that is, a hose that does not have a reinforcement inside, so it's flat.

00:44:25.101 --> 00:44:29.532
So you have to stretch it, then go to the valve, open it.

00:44:29.532 --> 00:44:30.922
It will fill with water.

00:44:30.922 --> 00:44:38.065
Therefore it will grow and from flat it will have a cylindrical shape and then water starts going.

00:44:38.065 --> 00:44:39.670
Normally the nozzle should be closed.

00:44:39.670 --> 00:44:45.525
Yep, but there's also stiff what we call stiff hoses.

00:44:45.525 --> 00:44:47.871
That is like a is like in a hose reel.

00:44:47.871 --> 00:44:50.246
It has already a cylindrical shape.

00:44:50.246 --> 00:44:54.429
This one can be wet inside the other one.

00:44:54.429 --> 00:44:57.041
For them to be stored, they should be dry.

00:44:57.041 --> 00:45:01.349
The wet one will be able to give less water.

00:45:02.663 --> 00:45:16.811
So presence of those standpipe systems that are meant for firefighters simply allow you to skip those sections of early operations and then, eventually, if that's not sufficient, you will add more and more and more to them.

00:45:16.931 --> 00:45:30.467
Yeah, correct a hydrant placed in a specific location that was assessed.

00:45:30.467 --> 00:45:39.898
It's a good place to put a hydrant, because maybe this entrance to a storage place or something In the same manner let's say, an outlet from a standpipe is in a vestibule that leads to a corridor.

00:45:39.898 --> 00:45:50.067
Yeah, so it's still a safe place, maybe separated by fire separation so that you can approach as close to the fire as possible and then start your firefighting from there.

00:45:50.501 --> 00:45:51.204
I think a lot of.

00:45:51.204 --> 00:46:06.320
Actually, this part I think a lot of fire engineers would be familiar with, because I'm not sure about all the places in the world, but we are doomed about calculating the range of the hose and does it reach the most remote part of your building?

00:46:06.320 --> 00:46:11.192
Because the law requires you to place them in such locations that you can reach them.

00:46:11.192 --> 00:46:18.748
So we're drawing those hose lines in our AutoCAD drawings you know the plans of the building to make sure that it's reachable.

00:46:18.748 --> 00:46:27.646
We're narrowing on time, but I really wanted to ask you some questions about your feelings and feel free to say whatever you like.

00:46:27.646 --> 00:46:30.663
You're retired, so they cannot fire you anymore.

00:46:31.304 --> 00:46:32.286
Your feelings about.

00:46:32.286 --> 00:46:37.523
Look, I'm a fire engineer, I want to do good job.

00:46:37.523 --> 00:46:39.286
There are some law requirements.

00:46:39.286 --> 00:46:42.981
They can tell me I need a hydrant every this and this meters.

00:46:42.981 --> 00:46:45.146
It shall provide one liter per second water.

00:46:45.146 --> 00:46:46.851
You know, there's a clause in my law.

00:46:46.851 --> 00:46:48.706
I can just take it and I'm done.

00:46:48.706 --> 00:46:50.927
But what if I want to do a good job?

00:46:50.927 --> 00:46:56.012
What if I really want to try and make a difference in my engineering?

00:46:56.012 --> 00:47:04.565
First, is this water supply a place where I can make a difference, Like by designing it better?

00:47:04.565 --> 00:47:08.333
Can I help you in any capacity?

00:47:08.333 --> 00:47:12.570
Or it's meaningless and I should find some other things to do?

00:47:13.460 --> 00:47:18.612
Well, I'm not sure if I'm the proper person to judge somebody's work.

00:47:18.612 --> 00:47:39.206
There's been so much knowledge and experience put into writing fire codes that, well, as long as the fire codes, then well, as long as the what I have a saying that, as long as the conversation continues between the operational firefighters and the prevention officers or fire engineers, we're on the, we're on the safe side, because the environment will be constantly changing.

00:47:39.206 --> 00:47:57.512
Yeah, but really I mean, our biggest challenges and concerns are outside of the scope of the work of fire engineers Vandalism, you know like somebody will just mischievously break something or steal a.

00:47:58.226 --> 00:47:59.000
Capsules or whatever.

00:47:59.059 --> 00:48:03.411
Yeah, whatever is necessary to operate it, you know, without loss of time and so on.

00:48:03.411 --> 00:48:19.003
So sometimes we keep in the back of our heads that we would like to be able to use the hydrant, but just for any case, because our lives are on sake, we will still refer to the traditional way of firefighting.

00:48:19.545 --> 00:48:26.387
And, in places, more of those hydrants, those tentpipes, to improve your chances.

00:48:26.387 --> 00:48:27.554
What would that change?

00:48:27.554 --> 00:48:38.661
That would probably change the amount of time you need to get water at the location where you want it, Because it's not that I can increase the outflow because of the pressure considerations that you've already mentioned.

00:48:38.661 --> 00:48:38.943
Right?

00:48:38.943 --> 00:48:41.309
So it's all about saving time in the end.

00:48:41.641 --> 00:48:43.925
Well, for me, yes, it is.

00:48:43.925 --> 00:48:48.153
But for me, as I said, you know, I have a philosophy.

00:48:48.153 --> 00:48:57.630
I mentioned it partially in the beginning and I will, let's say, say the full phrase Nobody builds anything with certainty it will catch fire.

00:48:57.630 --> 00:49:05.614
But firefighters know that whatever was built by human beings will sooner or later catch fire and we will intervene.

00:49:05.614 --> 00:49:08.759
Sooner or later catch fire and we will intervene.

00:49:08.759 --> 00:49:14.414
So in a way, you know, we have very little allies in the world of firefighting, because we are always the guinea pigs.

00:49:14.434 --> 00:49:30.771
You know, when shit hits the fan I'm not sure if I can say this Then we are the ones to intervene and it rarely causes anything to improve, other than when there's tragic loss of life, avoidable loss of life.

00:49:30.771 --> 00:49:56.590
So if we could really convince everybody that please be sure this will catch fire and then make sure that by saving the investors money, you are putting firefighters in danger because you can fulfill some requirements, but you can also build a better system that will protect the building better, you know, because then you know, I see there's many factors in play.

00:49:56.590 --> 00:50:01.251
There's insurance money, there's, you know, cost of running the building and so on and so on.

00:50:02.001 --> 00:50:07.679
I think it also the role of those systems also would depend on the scale of the building really.

00:50:07.679 --> 00:50:16.971
So if it's like two-story tall residential building that you can access from any external location you want, probably it's less of a trouble.

00:50:16.971 --> 00:50:24.228
But if you you have a 200 meter tall skyscraper, the reality of you having any any chance to to fight fire at the 50th floor is, yeah, it's really zero.

00:50:24.228 --> 00:50:25.510
So, first of all, the building shall defend itself, I guess.

00:50:25.530 --> 00:50:27.554
So sprinklers and stuff and have any chance to fight fire at the 50th floor is really zero.

00:50:27.574 --> 00:50:44.326
So first of all, the building shall defend itself I guess sprinklers and stuff and have wet standpipes and have good pumps, because in that case reliability of that water supply is really everything, because there is virtually zero chance that you can bring your own water up there right.

00:50:45.682 --> 00:50:47.068
Yes, it's very problematic.

00:50:50.452 --> 00:51:22.586
I mean you have to combat gravity and in this case the engineer has some sort of tools like pump systems, additional water supplies also those water tanks and for external firefighting, in terms of we've already mentioned wildfires and those areas and those fires which would have extreme large areas, not necessarily, you know, 50 megawatts in a 50 square meter of an apartment, but let's say 50 megawatts spread across a half a kilometer of a fire line.

00:51:22.586 --> 00:51:30.487
How different is water logistics in that case, and is there anything engineers can do to support that kind of operations?

00:51:31.659 --> 00:51:32.824
You mean like wildland?

00:51:32.824 --> 00:51:33.045
Yeah.

00:51:34.061 --> 00:51:36.085
Wildland or just large fires.

00:51:36.085 --> 00:51:43.643
When the wildland fires reach the neighborhoods, I mean we're lucky in Poland we didn't have those yet in that scale.

00:51:44.043 --> 00:51:44.264
Yeah.

00:51:44.344 --> 00:51:45.304
But yeah.

00:51:46.025 --> 00:51:58.610
I mean then the problem is that we have to choose between the amount of water and the weight of the hose, because in these fires you really have to make your steps.

00:51:58.610 --> 00:52:03.692
You know like you make your steps every day 9,000, 10,000, there you just go back and forth.

00:52:03.692 --> 00:52:08.192
So then you take a lighter hose or you take some water on your back.

00:52:08.192 --> 00:52:20.887
It's very straining and fatiguing, but what comes into play are airdrops, you know, like from bambi buckets, from helicopters or from planes.

00:52:20.887 --> 00:52:23.632
You know there's there's a variety of ways.

00:52:23.632 --> 00:52:26.150
I mean in in the united states and probably also in different countries where the there's a variety of ways.

00:52:26.150 --> 00:52:31.431
I mean in the United States and probably also in different countries where there's a huge problem with low-idle and fires.

00:52:31.480 --> 00:52:33.969
They also upright some dry chemicals.

00:52:33.969 --> 00:52:37.650
You know they just try to come up with different ideas.

00:52:37.650 --> 00:52:39.347
Just one correction.

00:52:39.347 --> 00:52:46.836
I just quickly checked these one liter per second are correct, but for internal hydrants and for external would be like 10 times that.

00:52:46.836 --> 00:52:48.938
So 10 liters per second, yeah, but for internal hydrants and for external would be like, uh, 10 times that.

00:52:48.978 --> 00:52:49.882
So 10 liters per second.

00:52:50.001 --> 00:52:51.887
Yeah, yeah, okay.

00:52:52.650 --> 00:52:53.373
Good, good, good.

00:52:53.373 --> 00:53:02.403
Uh, I remember quite clearly when there was a fire of the Notre Dame cathedral and president Trump tweeted like send the air tankers to take it down.

00:53:02.403 --> 00:53:08.914
So he was probably he was probably the pioneer of compartment fire tactics with air tankers.

00:53:10.463 --> 00:53:15.132
Look, surrounded by water, yeah, the Notre Dame.

00:53:15.132 --> 00:53:20.148
But the problem is that this water can just make the whole building collapse.

00:53:20.148 --> 00:53:24.889
You know that's not good for architectural monuments, historical buildings.

00:53:26.043 --> 00:53:31.068
Okay, shimon, thank you very much for for giving a water one-on-one to fire safety engineers.

00:53:31.068 --> 00:53:51.974
I always say that there are rules to be followed and you obviously show a huge respect to those rules, uh, and people who are writing them, and I also think it's a great achievement that we have codes and standards and and some ways to to really, you know, standardize the way how we apply stuff, but there's also huge benefits of people understanding what's the purpose of them doing so.

00:53:51.974 --> 00:54:00.579
You know you can apply those liters per second on your drawings in AutoCAD for your entire life, but not know how much a hose weighs.

00:54:00.579 --> 00:54:19.181
And I think having conversations like this, which bring this craft of firefighting closer to the fire engineering audience who are designing those systems for you, I think there's a huge benefit for that and I'm sure everyone who listens to to this episode enjoyed that and learned something new I definitely did so.

00:54:19.282 --> 00:54:23.932
So thanks, uh, once again for for joining me in this in the podcast well, thanks for having me.

00:54:24.000 --> 00:54:38.489
It's, I don't know, the third or fourth time, so I'm really honored and the message to everybody look, it's summer and since we're talking about water, don't forget to hydrate yourself okay, yeah, keep hydrated, okay, shimon.

00:54:38.530 --> 00:54:41.804
Thank you so much, and see you around see you and that's it.

00:54:41.844 --> 00:54:42.666
Thank you for listening.

00:54:42.666 --> 00:54:47.721
How much water do we need to find fires and how do we get that in the location where fire is?

00:54:47.721 --> 00:54:55.565
That were the main questions I had to Shimon, and I think he answered them both fully to my satisfaction.

00:54:55.565 --> 00:54:59.172
It was a pleasure to discuss Water 101 with Shimon.

00:54:59.172 --> 00:55:00.740
I hope you've learned something new.

00:55:00.842 --> 00:55:14.346
I hope that fire engineers, who never had a chance to view these elements of fire safety design through the eyes of firefighters, had a chance to view these elements of fire safety design through the eyes of firefighters, had a chance to actually think about those matters differently than they did before.

00:55:14.346 --> 00:55:21.090
In the end, what supply system is something we design precisely for firefighting, precisely for firefighters?

00:55:21.090 --> 00:55:29.119
We really need to make sure that these systems work in such a way that they benefit from them in the maximum way.

00:55:29.119 --> 00:55:36.012
So no space for wishful thinking, no space for us doing the design in a void.

00:55:36.012 --> 00:55:40.166
We need to talk to firefighters, and that's what happened in this podcast episode.

00:55:40.166 --> 00:55:45.547
Uh, shimon, thank you once again for appearing in the fire science show.

00:55:45.547 --> 00:56:05.288
You are a brilliant connection between the world of fire safety engineering and firefighting and I am so grateful that you allow me to tap into this connection and and join our beautiful groups together, and I think only good stuff can happen from more discussions and more podcast episodes like this one.

00:56:05.909 --> 00:56:07.371
I'll be wrapping up quickly.

00:56:07.371 --> 00:56:08.333
I'm on vacations.

00:56:08.333 --> 00:56:14.983
I try to stay hydrated, as Shimon asked, so I hope you're having a good time in your summertime.

00:56:14.983 --> 00:56:25.621
I hope you are resting a little bit with your families and if, in that time, you feel like learning some more fire science, there will be another episode next Wednesday waiting here for you.

00:56:25.621 --> 00:56:27.728
Thank you very much for being here with me.

00:56:27.728 --> 00:56:28.480
Cheers, bye.