Fire Science Show

Imagine if we had a tool that we could use to design a design fire. Instead of simply assuming fire growth characteristics by slapping the alpha-t2 function, use a tool that could tell us which items in a compartment burn and what the characteristics of that fire are. I would say this dream is shared among many fire safety engineers - I think we can all agree that we could use such a tool.

Today's guest, Dr Greg Baker, has shared this dream and built a tool like this within his PhD at the University of Canterbury. The skeleton was a zone model, and the tool developed has played with it well.  Actually, feel free to try it out in here.

In the episode, we talk about how Greg built up this tool and how it decides on the growth, plateau and decay of the fire. We also discuss how such a tool may be critical in a probabilistic approach to fire safety engineering and general performance-based design. Who knows, perhaps in the near future, such an approach will also help us run our CFDs. 

If you enjoyed this, you perhaps would like to read more:

• Benchmarking the Single Item Ignition Prediction Capability of B-RISK Using Furniture Calorimeter and Room-Size Experiments
• Ignition of secondary objects in a design fire simulation
• Developing probabilistic design fires for performance-based fire safety engineering

And a bonus:

• Ranking the Level of Openness in Blind Compartment Fire Modelling Studies

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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.

In today's fire fundamentals episode, I have chosen a difficult job: explaining how CFD modelling works without the ability to put a single equation out there! It's much tougher than I thought! I hope I've done a decent job, though.

I am trying to fill out this niche of talking about CFD at an approachable level. I've noticed there is a ton of 'introductory' level resources about modeling. Still, they usually very quickly go into mathematical formulations instead of explaining in plain language what is the purpose of specific models or modelling approaches.

In this episode, you will learn about:
- what is Computational Fluid Dynamics modelling;
- what is the role of conservation laws of mass, energy and momentum;
- what is turbulence, and why it impact our calculation so much;
- what are the common families of turbulence models (RANS and LES), and how do they differ from each other;
- what are sensitivity studies, and how does one choose an appropriate mesh for their problem?

If I had one book to recommend, it would be this book by Bart Merci and Tarek Beji.

If I had one paper to recommend, it would be this paper by Kevin McGrattan (open access).

Fire Science Show is produced in collaboration with OFR Consultants. Thank you for your ongoing support, that allows me to create content like this!

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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.

If the word 'uncertainty' sounds extremely boring to you, this episode will prove you wrong. I have invited David Morrisset from the University of Edinburgh to discuss his research on the subject. Whereas in fact David is establishing standard deviations, means and other statistical means of quantifying uncertainty in core fire measurements, the really impactful and important part of his research is on explaining WHY those uncertainties are there. Through physical explanation of processes happening in fire we may grasp a really good understanding why two HRR-time curves of the same object burned in the same lab, in the same way may be so vastly different.

These findings are fundamental for practical fire engineering. The establishment of design fires and their relation to the experiments is discussed in depth. We also talk about how we could establish better design fires for future engineering practice.

Some excellent further reading:

• Repeat Fire Tests of Upholstered Furniture: Variability and Experimental Observations - the upholstered chair paper
• Statistical uncertainty in bench-scale flammability tests - the PMMA paper 

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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.

This week, I am meeting up with Imperial Hazelab's Harry Mitchell, who is finalizing his PhD thesis on mass timber fires and, quite uniquely - including the smouldering phenomena in those fires.

As a part of Code Red experiments run by Arup, Imperial College London and Cerib (which you can learn more about from episode 111 with Panos Kotsovinos)  Harry has performed observations of formation, growth and decay of smouldering "hot spots" for up to 2 days after the fire. Based on that, conclusions were formed on the occurrence and persistence of the smouldering in large, open-plan mass timber compartments. This is precisely what we cover in this podcast episode - what is the smouldering fire of timber? Where can we expect it to happen? What are the potential consequences to the structure and people who need to enter it (firefighters and investigators?)

If you would like to learn more, please follow to these resources:

• Structural hazards of smouldering fires in timber buildings
• Flame spread characteristics in large compartments with an exposed timber ceiling
• Review of fire experiments in mass timber compartments: Current understanding, limitations, and research gaps
• Fire dynamics inside a large and open-plan compartment with exposed timber ceiling and columns: CodeRed #01
• Impact of ventilation on the fire dynamics of an open-plan compartment with exposed timber ceiling and columns: CodeRed #02
• The Effectiveness of a Water Mist System in an Open-plan Compartment with an Exposed Timber Ceiling: CodeRed #03

And other mass timber experiments covered in the Fire Science Show.

Fire Science Show is produced in partnership with OFR Consultants.

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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.

Tests in the world of reaction to fire are supposed to be representations of real fire scenarios, allowing us to grasp the characteristics of building products against them. While for the worst scenario (flashover fire) or the smallest ignition source (small flame), the definition is pretty straightforward. However, creating the intermediate method that the entire Europe would agree on was a bumpy ride. Our latest episode is a treasure trove of knowledge detailing the birth and maturation of the Single Burning Item (SBI,  EN 13823 ) test standard.  With the CEN SBI group  Convenor - Rudolf van Mierlo, we discuss the history and background of the standard, the background for some not-so-easy technical decisions and perhaps even tougher political ones. 

In a project of this magnitude, everything matters - how do you ensure the method is reproducible and repeatable? How do you convey the exact amount of information in the technical standard? Will one of the measures eventually be the one that defines the final classification, and what does the classification reflect?

Towards the end of the episode, we try to put those lessons from the creation and implementation of SBI into brainstorming a pathway for a new intermediate test we really need. An intermediate testing method for facades, as an effort for the Dutch government and a likely update to the existing ISO standard.

Link to the conference we have discussed: https://dgmr.nl/en/sign-up-for-dgmr-conference-fire-safety-in-an-sustainable-future/

Reading material:
- The Rise of Euroclass by Angus Law et al. - a more detailed description of the politics behind the standard
- The Single Burning Item (SBI) Test Method - A Decade of Development and Plans for the Near Future by Rudolf van Mierlo and Bart Sette
- KRESNIK: A top-down, statistical approach to understand the fire performance of building facades using standard test data by Matt Bonner et al. - a more detailed description of how the Polish method handles different facades

Also, if you enjoyed this episode, you will like this one too: https://www.firescienceshow.com/089-designing-law-by-disasters-or-not-with-birgitte-messerschmidt/

Cover image - Effectis press release on changes to the SBI standard in 2020 - also a valuable source to see how the standard is evolving.

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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.

I've finished my first large research grant! I guess that makes me a 'real' scientist now. Came here today to share some most interesting aspects of this project with you. Not going to bore you all about the wind and fire interaction physics (hey, there is an entire episode 50 devoted to that!), but rather talk about challenges and stuff that perhaps will matter if you would like to engineer a case similar to one we have studied.

So in this podcast episode, we will go into:

• How our framework for wind and fire coupled modelling worked out in practice (read more about the framework here Wind and Fire Coupled Modelling part 1 - Literature Review and here Wind and Fire Coupled Modelling part 2 - Best Practice Guidelines )
• How we had to go miles to modify the ABL profile so our wind predictions at the location of the fire are spot on 
• A bit on design fire choice, but plenty more in here: 135 - Contemplating a design fire for car parks
• And most importantly, how we handled the mass amount of data generated in 336 CFD simulations within the project. Our unique approach to statistics, indexing and risk.

The promised webinars will be uploaded soon, and you will find the link here.

Badania przedstawione w odcinku podcastu przeprowadzono w projekcie realizowanym an podstawie umowy UMO-2020/37/B/ST8/03839 do projektu badawczego nr 2020/37/B/ST8/03839 pt. Skutki oddziaływania wiatru na pożary budynków w wieloparametrycznej ocenie ryzyka z wykorzystaniem metod numerycznych.

Grafika autorstwa P. Jamińska-Gadomska (ITB) oraz P. Prusiński (NCBJ) w ramach współracy pomiedzy ITB a NCBJ w projekcie EuroCC (No 951732)

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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.

It is interesting to see changes in our profession that happen directly in front of our lives. Climate change and in consequence the changes in the wildfire patterns are one such obvious shift. In Poland, we do not ever have a ‘wildfire’ season, and I was kind of surprised when I discovered this is a thing in the South or in other parts of the world. Unfortunately, we do not have it *yet*. Some years ago devastating wildfire season happened in Sweden. There has been an emergency in northern parts of Russia as well. The summers are more dry – I thought that this is the driver of challenge, however, as with almost everything in fire science, the answer is more complicated.

I have invited Nieves Fernandez-Anez from Western Norway University of Applied Sciences  to discuss what is the ‘north’ doing to get ready for the coming threat. Nieves told me we do not need to reinvent the wheel – a lot of solutions, methods, approaches and policies do already exist. However, the wheel has also not been tested on all roads… Some things that can work in Spain or Greece won’t ever be feasible in the Scandinavia. Cultural and societal differences must be understood and accounted for when transposing solutions. The same comes to our models – they need to account for local vegetation, and its growth patterns. A challenge in itself, as we need a rapid increase in the amount and quality of information we have at hand.

I was a bit naïve coming to the episode, and the issue seems significantly more complicated. This is obviously an issue that a single researcher won’t handle. But here, another reason why I have invited Nieves. She is one of researchers who really get a lot out of collaborations in the COST network. Previously in COST Action Fire Links and now in the COST action on extreme wildfires. These networks connect scientists from different backgrounds and different regions, to create a thriving environment for knowledge exchange and crafting new ideas that respond to the new problems.

If you would like to learn more about changes in wildfires in Europe, refer to this paper.

COST Action Fire Links

COST Action european Network on Extreme fiRe behaviOr (NERO) (just started and open!)

Cover image - picture of wildfires near Ljusdal in Sweden, 2018, NASA Earth Observatory images by Lauren Dauphin and Joshua Stevens, using MODIS data from LANCE/EOSDIS Rapid Response and the Level 1; after Wikipedia: https://pl.wikipedia.org/wiki/Po%C5%BCary_las%C3%B3w_w_Szwecji_(2018)

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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.

This episode of the Fire Science Show welcomes once again Adam Barowy from the Fire Safety Research Institute to shed light on the pressing issue of fire hazards in electric mobility devices.

In this episode, we give a follow-up to ep. 085 with Adam, which was published one year ago. One year in the world of e-mobility is a lot of time, so we have a lot of catching up to do!

We tackle the complexities of standardizing explosion protection for large-scale energy storage and the implications of toxic smoke on human health. We delve into real-world case studies that underscore the urgency of our quest for safer battery usage and regulation. We also discuss the aftermath of an electric scooter fire on the Toronto subway, unravelling the potential danger these incidents pose in congested spaces and the evolving role of safety standards and research in keeping our communities safe. As we also discuss the role of certifications like UL 2272 and the promise of new standards such as UL 1487, join us in this episode to equip yourself with the knowledge to navigate an electrified world responsibly.

I promised Adam to plug in the https://batteryfiresafety.org/ - a public campaign focused on spreading knowledge in the safe use of batteries. 

Photo credit - a still frame from FSRI excellent video at https://batteryfiresafety.org/

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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.

In this episode of Fire Fundamentals, we dive into the life-saving choreography of fire detection and building automation systems that must work together in case of a fire. We discuss the roles and challenges related to:

• fire detection and signalling;
• control panels and fire scenarios;
• smoke control and compartmentalization;
• power and water supply and management.

We also discuss the sources of potential delays in device operation, and how some of those are consciously built into the system as a means for false alarm mitigation.

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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.

In episode 48, my guest Mike Spearpoint said that in mid '90s, he participated in experiments on vehicle fires, as at that time, there were doubts if the design fires of that time (developed in the '80s) were representative of modern cars. Fast forward 30 years ahead, and we seem to be in a very similar situation. We have limited knowledge on vehicle fires, most coming from very old studies that have used even older vehicles... And we have a fleet that consists of larger vehicles, gravitating to alternative fuels and batteries. We urgently need a new design fire, and in my opinion not just that - we need a new design fire paradigm for the car parks.

In this episode, I'm explaining the struggles we had choosing a design fire for our NCN OPUS grant on the multiparametric study of fire risk in wind conditions financed by the National Centre of Science in Poland. We have went through the literature, and looked through all of the available data, to figure out some data points we could implement in our studies.

In the episode, I will share those data points (and you may refer to a paper which I will link as soon as it is published), but also cover my ideas related to:

• how do we carry out experiments on vehicles, and how does the experimental setup change the outcome;
• what is the design fire, and why do we need one?
• what are the goals of our design and why design fire should start with the goals in mind.

The design fire is not a representation of a real fire. It is a test scenario that allows us to carry useful engineering judgement. This episode is all about this idea, and how I am making sure that my current assumptions reflect the changes in the modern car fleet. Enjoy!

Some additional resources:

• Mohd Tohir's PhD thesis that gives the best overview of data up to 2014
• Our paper from 2014 which explains some assumptions for the car park smoke control design and summarizes experiments (in Polish)

Badania przedstawione w odcinku podcastu przeprowadzono w projekcie realizowanym an podstawie umowy UMO-2020/37/B/ST8/03839 do projektu badawczego nr 2020/37/B/ST8/03839 pt. Skutki oddziaływania wiatru na pożary budynków w wieloparametrycznej ocenie ryzyka z wykorzystaniem metod numerycznych.

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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.