June 29, 2022

056 - Performance Based Fire Protection Engineer with David Stacy

056 - Performance Based Fire Protection Engineer with David Stacy

How does being a volunteer firefighter improve your abilities to do Performance-Based Design (PBD) and how your knowledge in PBD may translate to firefighting? That is not a question you can ask to every fire protection engineer, but luckily - David Stacy is one who can answer that fully. Tapping into his unique skillset and career path I try to extract answers on how does one translate firefighting experience into improved design. Where does he see the most immediate gain (duh - communication!), and how does a fire safety engineer seek knowledge.

And knowing that Dave builds his own machines and does his CFD, I would not be myself if we eventually did not venture into world of CPU's, BIM and difficult choices when managing uncertainties in commercial and scientific projects.

Join us in this multi-faceted episode, and hopefully enjoy the talk between two fire safety engineers, who are absolutely passionate about their work.

Oh, and make sure to check Dave's company - Performance Based Fire Protection Engineering webpage. Lots of great resources and more of them coming! 




[00:00:00] Wojciech Wegrzynski: Hello everybody. Welcome to Fire Science Show I'm today with David Stacy, alumni, full blood fire safety engineer, a firefighter, and a man who runs his performance based engineering business. Hey David, great to have you in the show. I'm happy to talk with a fellow fire engineer because, uh, the point of the podcast is to

[00:00:21] David Stacy: Thanks for having me excited to be here.

[00:00:21] Wojciech Wegrzynski: bring stuff that's useful to our community. And, I need a reality check what the community needs and you are, you are my reality check. happy to have this discussion. So, first of all, maybe tell us a little bit how you've ended up in your own company as, uh, you, you were a firefighter, right.

[00:00:40] Wojciech Wegrzynski: And, suddenly a twist in a career.

[00:00:42] David Stacy: Yeah, it was definitely, I have one of the more unique stories. I think most of us that fall into this profession actually, have an interesting story of how we got here. So yeah, I've always been involved with the fire service, you know, even back to, middle school, early high school days, , really involved with the fire service and that's what I wanted to do.

[00:00:58] David Stacy: but was doing good in school, wanted to [00:01:00] pursue, higher education going to university. So. When I was finishing up high school, I literally typed into Google firefighting college trying to find something that was hands on operational side, you know, on the firefighting side. And Maryland came up and Maryland's program, obviously the department of fire protection engineering, as well as the fire station there, uh, College Park Volunteer Fire Department.

[00:01:21] David Stacy: So I quickly realized I was a pretty cool opportunity where, uh, you'd have the fire, suppression side operations, as well as a world, world class, university, and degree opportunity. so got into Maryland, got my, my BS in fire protection engineering. And, yeah, even, even then, uh, when I was graduating, I still really enjoyed the fire service and wanted to go that route.

[00:01:40] David Stacy: had some good internships, with, N uh, whereas where I got by fire modeling startup when I was interning with there. Um, Steve Kerber brought me in there and Dan Madrzykowski was there at the time. So that was

[00:01:51] Wojciech Wegrzynski: Nice. Yeah.

[00:01:53] David Stacy: For sure. Got me on my feet and, also interned with the, then RJA now Jensen Hughes, uh, in their [00:02:00] Arizona office.

[00:02:00] David Stacy: So had some good opportunities. Um, so I, I knew those opportunities were there, but pursued the fire service, got hired as a career firefighter outta college with an engineering degree. And, once I got through the academy who was out in the fields, I, uh, looked back for, employment opportunities with an engineering firm.

[00:02:18] David Stacy: And again, at the time it was still RJA Rolf Jensen Associates in the Raleigh office, Raleigh, North Carolina. And, uh, they took me on pretty much was a part-time full-time position, you know, over 30 hours a week. And, uh, yeah, it's I had two full-time jobs. I still have two, two full-time jobs um, but I enjoyed doing both and, and yeah, I, I gotten, wide range of work types, but really found a niche doing fire modeling, specifically smoke control, performance based design.

[00:02:47] David Stacy: Was there for about seven years. Got my PE just realized that at that point, I had three children and it was a good opportunity to split off and start my firm. And, that's how I got, to where, where we are today. And, yeah, found it performance [00:03:00] based, fire protection engineering, which in the name, our go-to work type and our, our niche is, is fire modeling performance based, but we are a full service, fire protection firm.

[00:03:16] Wojciech Wegrzynski: You must have amazing SEO on your website. with with that, with that name. Yeah. But, uh, yeah, that's a, that's a nice, uh, that's a great story. And, um, You've been very lucky to touch so many aspects of fire engineering, like pursuing, top us one of the best of the world's fire science programs, exposure to Jim Milke and other great, people in UMD, especially that you've ended up being smoke control, experts.

[00:03:35] Wojciech Wegrzynski: So that's like the place to, to get started becoming one and having, for, for years, exposure to real fires. So that's, that is, , very. Rare somehow very rare combination in, in our field. And I don't really know that many, fire experts who would have experience from both.

[00:03:56] Wojciech Wegrzynski: , I'm not gonna lie. I knew that before. And that's one of the [00:04:00] reasons why I, I wanted you on, on the show, because perspective is truly unique in the world where we design systems made for safety. And in many cases made for firefighters. And from my experience with my firefighters around, I sometimes design stuff they don't really like or use or need or want, uh, somehow got in, gets in the code and I have to design it.

[00:04:24] Wojciech Wegrzynski: They don't know why. I don't know why the person who wrote the code probably is that for like 20 years, because it was in 50 years ago. And,

[00:04:32] David Stacy: it,

[00:04:32] Wojciech Wegrzynski: in this, you know, conundrum designing stuff for no good reason. So, going , into serious discuss. My first question is, can you see an immediate effect or immediate benefit of you being a firefighter and working with PBD systems with performance based design systems?

[00:04:52] David Stacy: it definitely is a benefit. I think it's in my day to day life, I may take it for granted more often than not my, uh, my coworkers and, and partners in my [00:05:00] company are, are reminding me like, Hey, Hey Dave, you know, your experience, you could really leverage that. And it goes a long way. the biggest impact, taking a step back and looking at it and seeing how it, impacts.

[00:05:09] David Stacy: And, um, we're able to utilize it to, to our advantage is how we communicate with, 37 jurisdiction with the AHJ's throughout the us. they are used to, I, I feel like, and, and this isn't a knock on other professionals in the field, but there's ways engineers talk, right. And within design teams.

[00:05:25] David Stacy: and then there's ways that you could communicate more effectively with AHJ's with fire marshals, fire inspectors, um, and building code officials. So I think what I've learned is I'm able to kind of flip a switch when I could be in one hour on a design team call talking to architects, mechanical engineers, structural engineers, and then 30 minutes later be talking to a AHJ.

[00:05:46] David Stacy: And I'm able to flip that switch and kind of communicate with them, in a little bit different way than they're used to. for example, if outside of a, a PBD project, let's say a simple, sprinkler design project where we're trying to have a conversation on where we should put the fire department connection.

[00:05:59] David Stacy: I've caught myself. A lot [00:06:00] of times saying things like, oh, you know, your first two engine company is, is not gonna pull in over here. They're gonna take the main address. They're gonna hit the hydrant across the street. So it makes sense for the FTC to be here. And you kind of see, especially if we're doing a video call with the AHJ's they're like, how's this guy know how to talk about that, you know?

[00:06:15] David Stacy: Or, uh, there's probably about very specific fire department operations. It, it gains some, buy-in not that you have to sell yourself, but it gains some buy-in where they're like, okay, this, this guy understands what we're trying to do as a fire department.

[00:06:28] Wojciech Wegrzynski: I loved it because it echoes my last episode where I said the number one skill is communication. And I love how you also put that on the very first place. And I, think any fire safety engineer with, problems, one hand having architects, other stakeholders who are not fire experts on the other hand, having client who is paying in is absolutely not the fire expert.

[00:06:52] Wojciech Wegrzynski: Uh, he's just, they're, just, uh, interested in not spending too much money.

[00:06:55] David Stacy: right.

[00:06:55] Wojciech Wegrzynski: the third hand, having, uh, the jurisdiction, the fireman, the [00:07:00] the code officials and so on, and, and with each of them, you have to communicate successfully. And with each of them, you require a different way of, of, of communication.

[00:07:08] Wojciech Wegrzynski: And do, do you think, um, for those, fire safety engineers who are not. involved in, fire operations because , well, honestly speaking, like not very much people would be actively involved, like you would said, and not many people would have time and, and will, and maybe are just not fit. It's also not smart to go jump into fire if you're not, trained.

[00:07:29] Wojciech Wegrzynski: But do, do you think there is a way how, engineers or, or fire researchers could get at least a touch of that to build up that mindset, to open up their view on, on these issues? Hmm.

[00:07:43] David Stacy: Sure. Yeah. I think there there's several steps that can be performed. the timing of it is one thing. Um, I've been involved in the fire servers for shoot almost 20 years. You know, although I was, I was a very young child, but I was going around the firehouse, hanging out, starting to learn stuff.

[00:07:57] David Stacy: So I've been involved for a long time and I picked up a, a [00:08:00] lot of, experience in history in doing so. But if you're completely green to the fire service, meaning you, you've never, been in a fire station, you never rid in a fire truck, no volunteer fire department experience, which is fine. I think a great first step is, is to reach out to your local jurisdiction.

[00:08:15] David Stacy: Firefighters are one of the most welcoming professions. Um, if you stop by a firehouse, with good intentions, they will gladly open their doors and bring you in. So I think as small, as informal as stopping by a station, telling the crew there, Hey, this is what I do as my profession. I'd love to sit down with you one time and talk about some challenges I've had with working with, building code officials, fire officials, with designing systems, determining if there's a disconnect, you know, Hey, do you guys like standby connections on the intermediate floor level or on the floor level?

[00:08:46] David Stacy: It's a great, I mean, they will talk for hours about stuff like that. , firefighters are very into the job. They're always trying to improve their, working environment and their operation. So they would welcome you into the station.

[00:08:57] Wojciech Wegrzynski: I agree. I love, talking with, firefighters. I [00:09:00] get exposed to them a little bit more. One reason because of the number of professional projects we carry. The second reason is that testing facility testing laboratories, like literally next doors to the regional training center for firefighters.

[00:09:15] Wojciech Wegrzynski: So they often come to our lab as protection for more dangerous experiments.

[00:09:21] David Stacy: yep.

[00:09:21] Wojciech Wegrzynski: then we often have to carry, we cannot carry open air experiments in, in our lab, but they welcome us in, in their lab where They have a permit because they're firefighters, they can do a little more than,

[00:09:33] David Stacy: Right, Right, They have some more

[00:09:35] David Stacy: lenient.

[00:09:35] Wojciech Wegrzynski: that's like this, a relation being built, but, outside of, Building like personal relation with, the local firemen, to my head comes UL as a great source of, of resources and

[00:09:47] David Stacy: Yes. Yeah, I was just gonna bring that up. Wojciech is, is to give a plug for UL and Steve Kerber and his group over there. What they're doing is for sure, the catalyst of, connecting, fire engineering, fire, safety, engineering, fire protection engineering, to the [00:10:00] fire service, um, actually science and data to fire ground operations.

[00:10:04] David Stacy: they've gotten away. And again, this is always very important in university, but from smaller analytical tests, type projects, which, which are great, right. Understanding, um, Flames in different conditions, flames and outer space. Like that's, highly, sought after and, and needed research.

[00:10:19] David Stacy: But what UL is doing is putting the practicality of actual fire around operations. How does a firefighter opening a door and not opening the bedroom window as a ventilation point versus opening the roof as a ventilation point? how, how does Aaron treatment, get affected by ho host stream application?

[00:10:34] David Stacy: guys are going crazy over this research, this data, and the way they deliver it is, is tremendous. And, I think other organizations are taking UL's lead, N has revamped, their database on, uh, heat release rate and, and design fire characteristics.

[00:10:49] Wojciech Wegrzynski: that is

[00:10:49] David Stacy: You know, it's, it's really looking sharp and it's, it's helping, um, get others engaged and, and have buy in on, on that research.

[00:10:56] Wojciech Wegrzynski: we switched the topic. Do you think it is [00:11:00] worth it?

[00:11:00] David Stacy: Absolutely. I think it's been a little bit of a challenge, specifically several years ago, , firefighters and the fire service is, , they don't like things to say the same, but they also don't like change. So, when data was starting to come out, right, there's a lot of, , hesitation and, , oh, that's just lab stuff.

[00:11:16] David Stacy: That's just science stuff. This is how you do it in the field. It took a little bit to break that threshold, break that ice. But now, I mean, I'll see it routinely in the station guys pulling up reading these reports, watching the videos cause we like watching videos versus reading. Um, and they're starting to get it.

[00:11:31] David Stacy: , and you'll, I mean, we've changed some tactics with my career department based on this research and, it's starting to be captured, holistically across, across that field.

[00:11:40] Wojciech Wegrzynski: Based on resources, but are you also, do you also see, in your job as a firefighter, the impact of, of you doing P B D and understanding in buildings more. Again, like compared to your colleagues who would not be PBD engineers or FEC engineers,

[00:11:55] David Stacy: right.

[00:11:55] Wojciech Wegrzynski: that impacting your everyday life? as a fireman

[00:11:59] David Stacy: I think there [00:12:00] there's certain conditions, more so on the training side in educational with, with my crew. I serve as a captain on, on my career department and with, within the department as a whole, we actually have a couple FPE on my department, which is pretty cool that are in operations, not, not prevention.

[00:12:13] David Stacy: So we're kind of looked at towards, some technical guidance, from Highrise, smoke proof, enclosures, stair, press systems, atrium, smoke control, and then, PBD. When we look at, um, we have a lot of vertical growth, a lot of growth going on in our city, decreased fire separation distances between buildings.

[00:12:30] David Stacy: And yeah, you can point out, even some products that I worked on personally, some of these performance based designs popping up in the jurisdiction. so it's a good opportunity to educate and, and teach guys about how that design, how that building was built. the effort that went into making that, condition, equal or improved to the prescriptive code.

[00:12:48] Wojciech Wegrzynski: I ask a lot about it because, you know, at some point I've realized there's a missing link between these two, groups of people, which in essence to succeed, they [00:13:00] need each other, you know, we need firefighters because our strategy is so heavily rely on firefighter intervention. At some point, only if you don't care about interior of the building or like if You're a hundred percent sure your compartmentation is gonna work. You otherwise you rely on firefighter's intervention and, we often take design decisions based on this hidden assumption in the back that it will happen.

[00:13:25] Wojciech Wegrzynski: And at the same time, firefighters need. us fire safety engineers, because in many cases, the fires in the buildings today grow so fast that we without active systems without good passive system strategy, it would be just impossible to fight, fires in a complex building. So, these two professions need, they need a connection and, and, there are connections being built, as you've mentioned, uh, there's many being built.

[00:13:49] Wojciech Wegrzynski: And in this, in this podcast, I would love to build one more. And that's why I'm so, so interested, , in this aspects of how life of a firefighter and performance based, , design [00:14:00] engineer for fire safety systems, how that twists together now, if you may take me to the, to your journey into performance based design, like you, you've made that a name for your company, but I, I would really love to, to hear what it is for you.

[00:14:14] Wojciech Wegrzynski: Like, how would you define what you are doing?

[00:14:17] David Stacy: Sure. Yeah. So, globally, um, and a lot of listeners of your, of your podcasts are familiar with performance based design

[00:14:24] Wojciech Wegrzynski: Hmm.

[00:14:25] David Stacy: in the states. obviously it's a design option. It's it's in international billing code. It's in adopted codes and standards. But what I will say is in again, in the us, it's definitely lagged behind other geographical areas of the.

[00:14:39] David Stacy: So, although , it's been there for quite some time, it's always been an option. Some jurisdictions are more hesitant to the approach. And, you know, again, from my initial experience in my early, portion of my career, I identify that was a, good opportunity. the tools and resources from what I've seen and from what I've been a part of are being developed to further enhance the, approaches and the [00:15:00] acceptance of performance based design.

[00:15:02] David Stacy: And yeah, I mean, from a business model, right. I see it being, more and more prevalent in the us. So I saw it as a good opportunity to say, design teams, architects, right.

[00:15:10] David Stacy: They're , ever, so, often increasing their design goals, their crazy ideas that we need to solve, right. , they wanna have the next best thing in building design, the tallest building, the biggest building, large open spaces. non-ED spaces from atriums in, arenas. And these things are, are coming down the pipe and the prescriptive code makes it clear, you know, right.

[00:15:32] David Stacy: In the introduction to , these codes that it's not meant to hinder, alternative ways of thinking, as long as it meets or exceeds the code. So that's how I jumped into P B D. and it's, quite accepted in the us. However, we do run into certain jurisdictions that are more reluctant.

[00:15:48] David Stacy: you know, when we come in there and say, Hey, we're, we're trying to justify an excess travel distance, um, from 250 feet to 300. And here's why, and here's our approaches. some jurisdictions are, I don't wanna say [00:16:00] plain it safe, but they really wanna rely on the prescriptive code, in this, in this current time.

[00:16:04] David Stacy: but we're, we're getting there.

[00:16:05] Wojciech Wegrzynski: Nice. I, always found based design, like, to me that is the engineering that, that other part is, is code speak or, you , or a cooking book style of engineering.

[00:16:16] Wojciech Wegrzynski: So that's the thing that, that's why I pursued this career. That's what I wanted to do with my life. Not, not apply your codes and standards, which awfully lot of my time is exactly that.

[00:16:28] Wojciech Wegrzynski: And, I know you are dealing mostly with, smoke control projects. there like the main aspect where you employ P B D and you've mentioned travel distances as well. Any other, um, aspects of your, work

[00:16:42] David Stacy: . Sure. Yeah. So with performance based design, as, as you said, smoke control is, is definitely one of our most prevalent work types in terms of, of fire modeling, FDS, Pathfinder and, and CONTAM for Highrise, , smoke group enclosures. We get into and, and technically those design approaches are, are not an alternative means and methods, not a [00:17:00] performance based design approach.

[00:17:00] David Stacy: they're directly allowable in the code. so within performance based design, I would say our, heavy hitters are excess travel distance. Um, fire separation, distance alternatives facing for methods of smoke detection, such as, beam pockets, you know, providing detection, every other beam pocket, maybe some advanced method of smoke detection, some air aspiration as, as an alternative to show improvement.

[00:17:22] David Stacy: tho those are the, some of the common PBDS, and then we get into some, what we have to be careful with performance based design is, is your decision on one aspect of fire protection, life safety can affect others. So, certain projects are more, uh, single lane, right? Solving one issue. But a lot of times we get into that holistic approach, which I know you're familiar with, cuz that's how the whole building is built.

[00:17:43] David Stacy: And that's the one part I think we lag behind here in the states is we have to make sure that what we're changing on one aspect of a project doesn't have an adverse effect on others. So I really enjoy the full holistic, methods of performance based design, where we're looking at sprinkler protection, smoke [00:18:00] detection, fire separation, rating requirements, uh, smoke control is thrown in there.

[00:18:04] David Stacy: fire department access, maybe fire department access is hindered and we need to provide an alternative solution to provide an equal, or greater level of safety the way we discuss it with our clients is basically any code challenge. Now we're not always gonna have a solution, but when, when they are stumped, when they say, Hmm, we never run into this, how can we solve this problem?

[00:18:23] David Stacy: That's when you reach out to a firm like mine and we're not gonna have a solution every time it may be something that we're like, no, I'm, I'm sorry. We, cannot get away from sprinkler protecting this high hazard occupancy. Just by doing a model. Right. But we do try to work with them. Try to come up with a pathway, moving forward for a solution.

[00:18:41] Wojciech Wegrzynski: modeling, access travels, smoke movement in general fire separation. And these all are, are things that you can. Verify through, through fire modeling. you mentioned CFD, uh, FDS software, I guess that's a big chunk of what you do modeling fires, in [00:19:00] buildings. Uh, I wondered as, a professional, what type of resources would you normally seek for this?

[00:19:08] David Stacy: so yeah. in terms of design fires, it's one of the topics I'm really interested in and I try to be involved with, that, you know, you have several committees, uh, through the S FPE doing design fire, database research.

[00:19:20] David Stacy: I was involved in a, in a research project through the S F P E as well as a coupled with Poole Fire Protection and the university of maryland, , where we looked at, a historical look at what information is available to us. , are there any gaps in information and where do we need to go moving forward?

[00:19:35] David Stacy: So I think as a professional, there's a little bit of a lag in, in more modern research coming out that come, that becomes available to the engineers. There's a lot of private, experimental data being developed a little bit, a lag coming out to the field. When you look at, , handbooks, SFE handbook, um, and other resources, you know, UMD has a design fire database on their website.

[00:19:55] David Stacy: N of course. A lot of these are relatively speaking, , dated, right? You have [00:20:00] old televisions, old wardrobes, the classic Christmas tree fire that everyone likes to reference. Right. But at a certain point, when we're going 5, 10, 15 years down the road, when do we have to think about, okay, what am I using as my basis of design my design fires?

[00:20:14] David Stacy: What are my fire characteristics? My soot yield is that appropriate for this building? So , the resources are there. but I just think surely, there's gonna be a framework to, to continually develop that and make it accessible, across all engineers, the, um, with your involvement with SAP as well, and , the standards making, , standards committee for performance based design, right?

[00:20:33] David Stacy: That's one of the goals to kind of globally try to align us all. And through discussions, even on that, it's like, well, do we say you do a five megawat fire in any atrium? That's four stories. And, and the answer is no, because we do need to have some allowance for that engineer to make that decision, or, or what should the soot yield be in that. I think in the end, we always have to have that, area of interpretation and justification for the engineer. Um, with that being said, hopefully we continually [00:21:00] update our database and our resources available to us.

[00:21:03] Wojciech Wegrzynski: And what about like, for me as a, as a researcher, as a scientist, first steps would be towards places like Fire Safety, Journal, Fire Technology, like scientific publications. And give me an honest answer. You, do you think these things are accessible enough for engineers? you didn't mention them, so I guess it would not be your first step to seek them.

[00:21:23] Wojciech Wegrzynski: And I truly wonder how engineers would use this type of resources and if they don't use it, you have any idea why?

[00:21:32] David Stacy: Yeah. great question. I find myself, , within those journals, you know, the fire safety journal and some of. More technical resources when I'm looking for something very specific. So perhaps, design, fire characteristics, or heat release rate from, a certain energy battery or, um, a certain vehicle type within, or, or a certain occupancy.

[00:21:53] David Stacy: That's usually when I get driven to those, and I'll be honest, sometimes , I'm doing Google searches, just trying to gather all my resources.[00:22:00] you know, what you have to be careful of, right. Is you just don't see one number and you're like, okay, that's what I use. But part of my process, uh, again, for a very specific, approach or analysis is find as many resources I can and references, I save them in my project file.

[00:22:13] David Stacy: I, I read 'em all I highlight appropriate sections. I try to, correlate it all together to come up with a conservative, basis of design for that analysis as far as readily accessible. I mean, some of them, are subscription based or you have to, purchase articles, which is fine.

[00:22:27] David Stacy: Some are thesis, , that are defend, which are great to reference and utilize. I think that it's, everything out there that you need as, as an engineer. it is attainable. It's just the, the level that you go to find it. again, for instance, I feel like, you have to be careful where you just don't find one resource and you say, okay.

[00:22:45] David Stacy: Yep. Uh, 550 kilowats is what I'm using for my design fire. You really have to look into the weeds, make sure it's a well vetted, experimental set. And then, and then go from there.

[00:22:55] Wojciech Wegrzynski: And, on your like everyday reading list, I, I would assume you would closer to like [00:23:00] reading fire engineering from SF P than, than just browsing through FSJ, uh, as, I mean, F journal, uh, on a daily basis.

[00:23:07] David Stacy: I I'll be completely transparent. I'm not a, , yeah, I'm not a daily reader of, of FSJ.

[00:23:12] Wojciech Wegrzynski: Don't think it is like as a negative trade because , it is absolutely not. And I am an academic and I would not consider my self, a daily reader. It's just this, assumption that we, as a fire scientist community, we try to, build, solutions, find, make research that eventually is is a utility , for the community.

[00:23:33] Wojciech Wegrzynski: But I also see, there's, and again, a missing link between the worlds. Like, I, love how you. Frame this this searchability or ability to, figure out does a source exist. And if it does where it is and if it is, how can you access it? So there's like this, glass walls that need to be breaking.

[00:23:56] Wojciech Wegrzynski: Like you have to be very intentional to [00:24:00] actually get to a scientific paper and get

[00:24:02] David Stacy: Yes

[00:24:03] Wojciech Wegrzynski: out of it.

[00:24:04] David Stacy: exactly. that a hundred percent that's, that's exactly my point. And, going back to that last group, I was a part of, with the design fire database project, sponsored by the SFPE foundation. Uh, that was pretty much the result is right. The grand goal would be, yeah, a one stop shop, a database of everything and anything from, government research to private research, to just engineers that say, Hey, I justified this based on ABC putting it into one searchable database.

[00:24:29] David Stacy: It sounds great. We would all love that. Right.

[00:24:31] Wojciech Wegrzynski: Yeah,

[00:24:32] David Stacy: the, the effort of both, collaborating, contributing, vetting the information, making a graphical interface, that's searchable. is it achievable for sure, but it's gonna be a good amount of effort, but that was pretty much the result Of our research and, and gap analysis in that project is it would help the community. It's gonna be a lot of work. There's a lot of steps to be taken. And, uh, we're kind of looking for a direction if, if it's gonna move forward to, to pursue that or.

[00:24:56] Wojciech Wegrzynski: what you're saying now is actually amazing because unfortunately, the [00:25:00] things you just mentioned are very uncompatible with, with the journal papers. However, the knowledge could be transferred in, in that way. And that that's something I need to talk with my colleagues. In higher places, the editors and other, who pull the strings, in journals, because if we want to make, science more accessible, it's not about building more walls and more sophisticated knowledge pouring into the, journals, but maybe finding ways how to actually, get this knowledge, to people.

[00:25:33] Wojciech Wegrzynski: And, is something I would love to, to see. Okay. Enough rumbling about, journals and, thank you for your openness and honesty to, to talk about that.

[00:25:40] David Stacy: Yeah,

[00:25:41] Wojciech Wegrzynski: You've mentioned before that, in your communication with authorities, you have to them for a Now you've also told me before that you have some like steps or process or, or your approach, to [00:26:00] communicate with them. So maybe you can, you can share if, if it's not like trademarked and

[00:26:05] David Stacy: no, no, no.

[00:26:06] Wojciech Wegrzynski: Yeah. It would be great patents, a way to convince authorities. I'm right.

[00:26:11] David Stacy: so first it's yeah, it's, it's not so much to convince them that, Hey, you know, you gotta sign off on our solution. It's gonna work. It's fine. Just, you know, sign this doc document. More. So if you wanna use the word convinced on the overall approach to, welcome the analysis and the possible pending acceptance of it.

[00:26:29] David Stacy: So, , no, our process is not proprietary. , what I would say it's definitely following the projective path of, as I mentioned, that the SFP standard making committee on performance based design, where we have different chapters on what's required, from your obviously identifying your scope and your project goals, your performance metrics, having a design brief, having your final report, all these steps , are being developed back a house right now and on.

[00:26:55] David Stacy: And just to be clear that the goal of that standard making committee is to make an annex [00:27:00] material , to the building code structure so that the AJS have a resource. They say, okay, I'm being asked to entertain a performance based design. I have no clue what that is. Here's appendix material to the building code that helps me understand and accept this approach.

[00:27:14] David Stacy: So that is gonna be huge, especially in the states, cuz again, we're we're behind on that front. so in terms of right now, what do I do? Because that isn't necessarily in place yet. our approach is very methodical , and direct with them. So even if there's certain jurisdictions that we work with quite a bit, they're familiar with us as a firm with fire modeling and P B D um, holistically.

[00:27:36] David Stacy: so they, they understand it, but regardless we always, first what we do is called a letter of intent. It may not be a fiscal letter, but it's at least a discussion with them that says, Hey, we're working with so and so client here is their code challenge and here's how we're gonna go about attempting to provide a solution.

[00:27:55] David Stacy: So for instance, it would be, Hey, we have a, building with exterior [00:28:00] openings that exceed 60% and it's eight feet from a adjacent building. And obviously that doesn't meet the extent of the IBC for fire separation distance. We're gonna do a performance based design approach to find an alternative, to prove equal or to, or greater resistance for the specific situation.

[00:28:17] David Stacy: Would you entertain that? That would be the discussion with the AJ, they would say, yeah. You know, we we've seen that before. We we're willing to entertain it. Now we have our buy it, on the approach, not, not the solution, there's some cases where they say, oh no, no, that, you know, fire modeling,

[00:28:32] David Stacy: we we don't

[00:28:33] David Stacy: believe in that, you know?

[00:28:34] David Stacy: Yeah. you know, you're just gonna put, garbage in and it's gonna give you the solution which can happen right. Garbage in, equals garbage out. So at that point, we take a step back. We help to provide some education on our next steps, moving forward. Getting their, buy-in and, collaboration throughout the process, making them feel comfortable with it.

[00:28:52] David Stacy: Usually we're successful with that. What that next step looks like is, is the design brief portion. So internally we're going through, we're looking at our design [00:29:00] documents, getting a method of approach, a methodology on how we're gonna solve this code issue or attempt to solve this code issue. Maybe it's to provide additional sprinkler protection, increase the sprinkler design density, uh, make some architectural changes, whatever it is that we think could prove this solution.

[00:29:14] David Stacy: And we're then gonna develop the design brief and the design brief. Again, it reiterates the code challenge of issue prescriptively. What we're trying to overcome is, again, the us is based on a prescriptive code. So if we can't meet it, we have to provide the alternative. So it would identify what that is.

[00:29:30] David Stacy: It would identify what , our basis is gonna be, how we're gonna go evaluating that condition, what our performance metrics are. And this is where, what we were discussing earlier on design fire. We're gonna explicitly say in this portion of the, of the analysis, we are gonna evaluate an axisymmetric fire with energy based on four sprinklers activating.

[00:29:51] David Stacy: And that's gonna be our design fire, or we have justified two couches burning simultaneously our as our design fire.

[00:29:59] Wojciech Wegrzynski: So here you [00:30:00] would not only say, we follow this generic guidelines or we do it like everyone else, but you would like point to specific choices you've made with providing already providing, explanations for these choices based on engineering knowledge, um,

[00:30:15] David Stacy: Yep.

[00:30:16] Wojciech Wegrzynski: sources, databases, and, and fire science in general.

[00:30:19] Wojciech Wegrzynski: Yes.

[00:30:20] David Stacy: We do that at this step, as well as justify our performance metrics. So what will be the past fail, whether, you know, for tenability or, heat, flux, wall temperature, whatever our performance metrics are. We couple, both of those in this design brief. Now it's not to say they can't change, based on some type of, or, design change moving forward.

[00:30:38] David Stacy: However, if they do change, we better have a good reason and justification for it. What this does is it protects the analysis. , as we've all seen in our professional career, right? there could be cases where someone's designed a smoke control system, , mechanically and architecturally they're limited to only 80,000 CFM and they make the design fire work for them.

[00:30:57] David Stacy: Right. That is what we don't want to do. [00:31:00] And that's how we protect, the city, the AJ, our client, and ourselves as professionals by saying, this is how we're gonna do the analysis this way, when they get our final report, which is the final step after we do the whole approach, they don't see that.

[00:31:13] David Stacy: Okay, well, you modeled a 1200 kilowat fire in your design brief. You said 2,400 kilowatt. What was the change here? Why, was there this reduction. and if we don't have a reason for that, right. It's a flag of, okay, well, did you make this analysis work? Which of course, jeopardizes us as a profession, right.

[00:31:28] David Stacy: And is not a ethical thing to do. So that's overall our approach to P B D uh, that letter of intent, or discussion on what we're gonna do, the design brief, which outlines further details on what we're gonna do. And what's the pass fail criteria. and the HJ, the stakeholders are involved in all of this, so that they feel, and they are a part of it.

[00:31:48] David Stacy: if they say no, you know, yeah, you modeled a fire 10 feet from that exposure, but , what if there's a car in between them? We wanna see the car. . Right. So that gives 'em the opportunity to do that. And then we go ahead, do the [00:32:00] analysis issue, the final report. And by then everyone's been engaged the whole time.

[00:32:03] David Stacy: They understand the concept, they understand what we did, how we got to the conclusion. And it's a, it's a well validated and, smooth approach.

[00:32:10] Wojciech Wegrzynski: And out out of curiosity. And how often would you be like checked by the third party consultants? the culture in, in there? Hmm

[00:32:17] David Stacy: Yeah, I honestly, I feel a third party reviewer is very important and in the standards making committee, it is gonna be a, a component of it. But honestly, again, I'm, I'm always very transparent with any discussion. I would say, , just shy of 50% is our work currently being engaged by a third party.

[00:32:37] David Stacy: the AJ doesn't have to engage a third party currently in the states. I'm, I'm not sure about in your area, but they do have the option to, and it's at the cost of the client. So, , some AJS, they may have a FPE on staff and are well familiar with this and feel comfortable reviewing it. So it's not that it doesn't get reviewed, , smaller cities, smaller jurisdictions.

[00:32:58] David Stacy: That is typically where we see them [00:33:00] say, I don't even know what I'm reading here. I'm gonna hire another engineering firm to, to review this.

[00:33:05] Wojciech Wegrzynski: If you curious how it's in here, we very rarely would have a real third party check I think a lot of responsibility falls down on the firefighters for a common solutions, you just go with the code and, and even if you do like P B D for smoke control, it is a very.

[00:33:26] Wojciech Wegrzynski: Common thing to do in here. So the knowledge is well propagated within the community, and most people can tell assimilation is scrap by looking at it. it's well developed, like, developed thinking here. And if you have a

[00:33:40] David Stacy: Wow. Okay. Right.

[00:33:40] Wojciech Wegrzynski: that exceeds, for example, your Flo or, or, evacuation path length, or between buildings, , you would go , into some sort of irrigation process from the low, which includes gaining opinion of your regional fire service, the state fire service at some point, and these guys are, very experienced.

[00:33:58] Wojciech Wegrzynski: So in a way, they take [00:34:00] the responsibility of the third party on themselves if they like it or not, if they're aware of that or, or not, though I'm tunneling projects in which I'm very active, it happens.

[00:34:08] Wojciech Wegrzynski: and this, I think a nice thing, but it it's difficult and, it adds time to the, to the whole process. And I also had to, in the meantime, when you were talking, I had to recalculate how much 80,000 CFM in human unions is.

[00:34:21] Wojciech Wegrzynski: And that's, that seems to be 130, 5,920, cubic meters per hour.

[00:34:28] David Stacy: Oh, yeah, That's

[00:34:30] David Stacy: funny. Yeah. Yeah. I apologize for my,

[00:34:33] Wojciech Wegrzynski: no, no, it's it's it's okay. it's your problem at ours? sorry. I, I was once forced to, to, to calculate BS and, pressure explained in like, per square inch or

[00:34:47] David Stacy: my English, uh,

[00:34:47] Wojciech Wegrzynski: or

[00:34:47] David Stacy: units. yeah. Yeah.

[00:34:49] Wojciech Wegrzynski: that was, something that, that was absolutely something, in, I was writing down your process because I really like it.

[00:34:55] Wojciech Wegrzynski: And I wrote one word in other color education. So, because you are repeating this [00:35:00] process on and all, is this education still like, individual base, like this client is this, so we prepare special presentation for that. Or you already have like, resources you refer them to. And, if so, how would that database would be billed?

[00:35:17] David Stacy: Yeah. Most of, uh, yeah, as far as the overall process, , it's more individual, where we do have some presentations to, to run them through. , we're actually working right now in a really neat infographic that, that goes through each of these steps that, that I kind of ran through quickly. Um, I think it ends up being it's a little more detailed.

[00:35:32] David Stacy: There's like 12 or 15 steps and, uh, we will be rolling that out soon. So I'll get it up on my website and that'll be available for, for everyone to, to check out and use as a resource. .

[00:35:40] Wojciech Wegrzynski: what would be the website? The address I'm gonna link it.

[00:35:43] David Stacy: So it'll be our, it'll be our firm's address, which is P B F p.com performance based fire protection, engineering.com.

[00:35:50] Wojciech Wegrzynski: Nice.

[00:35:51] David Stacy: uh, it's not up there yet. Um, we're working on rolling it out, making it all, doctored up and pretty. And, uh, but it will be a nice resource that we look forward to

[00:35:57] David Stacy: sharing with people.

[00:35:58] Wojciech Wegrzynski: People in the audience, just [00:36:00] check it every day and get that man. Some Google credibility by a lot of, by an inflow of clicks to his webpage,

[00:36:06] Wojciech Wegrzynski: um, in the end, I, I really wanted to talk to you about

[00:36:09] David Stacy: Yeah.

[00:36:10] Wojciech Wegrzynski: like every everyday job as a fire safety engineer and someone, who's doing modeling a lot. And, , how does your routine or working on the model like I really wonder how the difference from my, I see post your company in LinkedIn, and they're always interesting, and I, I see these amazing models and I'm really cur curious, like, for example, do you work a lot with BIM models and transfer them to FDS?

[00:36:36] David Stacy: Great question. Yeah. Great. Que yeah, I'll be happy to share some of that with you. So as far as I'll kind of walk you through it through a model build, I guess will be the easiest way. I love BIM models. I love Revit models. What I will say is in most cases, we are not directly, , importing those and utilize them as our base model built.

[00:36:53] David Stacy: The approach that we, you can do, through using like P thunderheads M is you can take a bin model, [00:37:00] get it as a IFFC file and import it into M what I've found in my experience is, you know, obviously creating your mesh around your domain, you could take the obstructions and thicken them all to try to snap 'em to a mesh.

[00:37:13] David Stacy: but especially in very complicated projects and buildings, I found that that snapping is, is very difficult to regulate, right? And a lot of times we get engaged pretty early, even what we call schematic design phase or early design development, where that Revit model isn't entirely completed. So, uh, yeah, you may have solved my post just the other day on, on identifying leakages in, in,

[00:37:34] David Stacy: a,

[00:37:35] Wojciech Wegrzynski: that was that's the thing I thought. Wow. Leakage. Like my models don't really leak in fact, I, I didn't like put it in, the context of BIM I hear you. I have the same,

[00:37:47] David Stacy: mm-hmm

[00:37:48] Wojciech Wegrzynski: same issue for years. And, mine is, not leakages. Mine is, I, I don't use structured mesh.

[00:37:56] Wojciech Wegrzynski: I use unstructured mesh, which means that I [00:38:00] try to put my mesh elements in very different fashion, everywhere. if my software, my measure finds, , obstruction next to a wall, which is like 10 nanometers away, like one pixel. In AutoCAT on print. You cannot see that walking through Revit model. You never see that.

[00:38:19] Wojciech Wegrzynski: But if there are two lines, which you see as one, it's gonna try and put a mesh between them, which ends up in, in really bad errors. So it's like the work with this type of operation is 99% cleaning up

[00:38:34] David Stacy: Yep.

[00:38:34] Wojciech Wegrzynski: importing. Yeah.

[00:38:36] David Stacy: A hundred percent, same issue. So yeah, that, that specific video we're talking about, that was a, quick opportunity from a client where they wanted to have a rough order magnitude of exhaust.

[00:38:45] Wojciech Wegrzynski: Mm-hmm

[00:38:46] David Stacy: yeah, to be honest, we, we took their Revit model. We put a mesh on it. I tried snapping obstructions.

[00:38:51] David Stacy: And as you, you could actually see it in the video. there are numerous leaks, so, so very specific instances would we do that most often? good old [00:39:00] fashioned taking floor plans, CAS or PDFs, marking them up, using them as backgrounds and, and building that model. From scratch, by using solid obstructions of the walls, right?

[00:39:09] David Stacy: Floor slab, assemblies, like you said, when I do it that way, I know that model is built correctly with a few exceptions. We may miss a couple overlaps or something, or we misalign our meshes, but that is my preferred approach, even in a larger arena. maybe we just have the model specific portion of that arena.

[00:39:26] David Stacy: Again, taking that rev model one. It's a huge file. It's very cumbersome, difficult to work with. And as you said, in my experience, the time it takes to clean it up outweighs the time it takes. If I just built it individually

[00:39:39] Wojciech Wegrzynski: zero.

[00:39:39] David Stacy: from scratch. Yeah.

[00:39:41] Wojciech Wegrzynski: From from the dimensional role. Yeah. And, and you said you sometimes, like in this project you were asked for , quick, rough So, so that's, that's interesting. I wonder how you deal with that in terms , of the quality of the model , do you run sensitivity studies or you are just okay with, uh, the uncertainties because it's a [00:40:00] rough

[00:40:00] Wojciech Wegrzynski: assumption.

[00:40:01] David Stacy: Yeah, more so the later, , with that disclaimer to the client, you know, Hey one, right? Typically we don't have a design brief, we don't have a basis to design. So we do have to be careful here cuz when we model, say I throw in some sprinkler links and I do a quick sprinkler activation count that that's great.

[00:40:15] David Stacy: And, and that's good initial info, but yeah, no, we're not doing full sensitivity. We're not looking at winter conditions for makeup air, summer conditions, wind mesh, cell sensitivity. We're not going to that extent. , but in general, if we have some level of conservatism in there, we get a general sense of how we expect the system to work, especially a simple smoke control exhaust case.

[00:40:36] David Stacy: We'll get them in the order of magnitude. And I'll, say, Hey, I think you're gonna be between a hundred and 140,000 again, CFM. but, uh, and you need these doors to open again. This is just a quick picture. As you develop your project, we're gonna have to dig into this more fine, more so it's just initial one.

[00:40:54] David Stacy: Maybe the client's like, oh, I didn't know I was gonna have an atrium. What's this gonna look like? They wanna get some quick numbers to get some [00:41:00] pricing together. Uh, cuz atriums are expensive, right?

[00:41:03] Wojciech Wegrzynski: Yeah.

[00:41:03] Wojciech Wegrzynski: they are, and in your, but in your routine, , you would like, assume that you are going to refine this in

[00:41:09] David Stacy: yes. Yeah.

[00:41:10] Wojciech Wegrzynski: and your final product would be like this, but on the timeline, you just have this five days to give a rough assumption or a week or, or two weeks, and then you have like a month to finalize.

[00:41:20] Wojciech Wegrzynski: so ask that because in fire science, what I often observe is, and I hate it. I, I, I hated the most, a lot of people write a scientific paper and they would just drop like, half meter mesh and would say they were limited by the computational capabilities of their laptop or something. And, and just live on with that.

[00:41:37] Wojciech Wegrzynski: And then again, I see the market, I see consultants, which are not okay with such simplification and are like, you are very open about the limitations and our S and I see scientists that are super okay because they had to get the paper pushed. And I, I hate this fully. how do you find like your verification [00:42:00] validation of, of your models, you do that yourself, or you rely on fire science and you use FDS because it's the most validated probably tool we have

[00:42:09] David Stacy: Yeah, we, we definitely do stay pretty much within the FDS framework because of the extensive validation and verification. , but yeah, to fully paint the picture. And in this specific instance, we would, you know, say we're engaged with that client for a full smoke control, rational analysis, right. Of a written document that has all that, uh, incorporate into it.

[00:42:27] David Stacy: We may tell them, Hey, we'll get you an initial idea within a week or two, some rough modeling. We need to refine that. And then yeah, sometimes they're taken aback by how long we say we need, four to six weeks for, a simple atrium kind of seems crazy to them, but that's what it takes to get through.

[00:42:43] David Stacy: Like you said, to do, uh, all the sensitivity on our extreme environmental conditions, atmospheric conditions, pressure, as well as, , mesh sensitivity, you know, most often we're making sure that we're, we're falling within all the parameters. you know, D star QStar that there's been studies where it has been, been found, not be as [00:43:00] detrimental as, as originally thought, but we do try to stay within those and at least do the due diligence to range our cell size.

[00:43:06] David Stacy: See how that affects the results. In most cases, again, for a simple smoke control system, it's usually not gonna throw you off by, by a large order of magnitude, but you may see, see, uh, minor variances.

[00:43:18] Wojciech Wegrzynski: and these performance metrics for the model itself are, is this also in a way communicated with the AJ during the process and with the client? it is in your initial draft. Like we

[00:43:29] David Stacy: Yeah,

[00:43:29] Wojciech Wegrzynski: this to be like that.

[00:43:31] David Stacy: absolutely. Yeah. I mean, so when we look at tenability, , there's been numerous cases where, , internally we like to look at visibility at six feet, through a light emitting sign we'll, we'll increase our visibility factor. for certain occupancies, sometimes we'll keep, we'll maintain it at a more demanding value, but we've had, we have had certain ahas that say, oh no, I would like you to maintain visibility at eight feet because your egres sign is normally at eight feet, you know, it's above a door.

[00:43:55] David Stacy: Yeah. Great. Well, we will do that for sure. So yeah, we do that during the design [00:44:00] brief stage, before we do our

[00:44:01] David Stacy: final models. Yep.

[00:44:02] Wojciech Wegrzynski: That's cool. And, going into the calculation, , process, I know you, you are building computers. I'm also following that on, on LinkedIn. And I love that content , that you provide, but, there's a debate like cloud having in-house computer. I am also in the middle of that decision actually.

[00:44:20] Wojciech Wegrzynski: we were also in the middle of purchasing a new supercomputer for ANSYS, just going fully , into collaboration with another Institute. I've also published that on LinkedIn some time ago, we've done very nice sensitivity studies with them, how fast we can go. And then that's a banker like, I guess you must go through the same, challenges

[00:44:38] David Stacy: Yeah, Yeah, for sure. I mean, it's definitely a cost benefit analysis for us. you know, when I first started my first fire line project yeah. I was using, cloud based programs. And as we grew, we did our first model machine, our second model machine. And yeah, now we're building our, our fourth.

[00:44:55] David Stacy: We're starting to put them into a rack arrangement where we can network them together. , and we're having a lot [00:45:00] of, a lot of fun and success with. so there's two sides of it. one, for the most part, we're able to handle our capacity in-house and with those in-house machines, I'm able to fine tune them and, and put in right.

[00:45:10] David Stacy: The hardware that I, that I need and want, I'll give some plugs. So , we're using AMD, rise, thread, rippers. Um,

[00:45:17] Wojciech Wegrzynski: Uhhuh.

[00:45:17] David Stacy: people have been talking about that in the field. Hey, are, are they working well for FDS? What are, what are limitations to them? I personally love them. I, I think Ryzen is starting to get away from the thread ripper platform.

[00:45:28] David Stacy: , cuz they're, they're improving their, their more baseline, , processors a little bit. So I don't know how long they're gonna support or keep that, product line going. But I mean we're getting four, 4.2 gigahertz of, of processing speed on these they're pumping, you know, they're moving quite well. Yeah. So I like to keep 'em in house, we're running models quick. we're able to do, do our validation sensitivity. That being said, like just these past two weeks, all three model machines are at a hundred percent capacity. So we still leverage those cloud computing, servers. Um, we use [00:46:00] Sabalcore quite a bit.

[00:46:01] David Stacy: Um, it's a great platform. You know, the limitation is they to be honest, they are a little bit slower. but they're

[00:46:06] Wojciech Wegrzynski: Hmm.

[00:46:06] David Stacy: They're doing the maintenance on them. Uh they're on standby power. They meet certain, federal regulations with security standards. So there, there is a lot of benefit to it.

[00:46:15] David Stacy: And, we're cyclical. When we get really heavy, we, we put, I think I have 12 iterations going right now on stable core. So yeah, we, we use a combination of both.

[00:46:24] Wojciech Wegrzynski: and that's probably the, choice we're gonna follow, , as well, like with the in-house beast ready on demand. And I also like the versatility to run my own scientific projects on it. Whenever I like without like asking for more money to, pay the, cloud, fee I usually have.

[00:46:40] Wojciech Wegrzynski: I love how this, computational power and, capabilities cheaper and easier than ever before. again is against that. What I've meant, what I had most seeing like, oh, I was limited with my, with my computer. No, one's limited with your computer having [00:47:00] Amazon service or sub or, or other cloud services out there is just a matter of budget and, and termination and people would spend like thousands of, of thousands of dollars on, on fire tests to publish a paper. And, why are we justifying, um, bad work in here?

[00:47:18] Wojciech Wegrzynski: Ah, just, I'm sorry. I'm ranting,

[00:47:19] David Stacy: Yeah,

[00:47:19] Wojciech Wegrzynski: annoys me. I annoys the hell of me.

[00:47:21] David Stacy: no, no, I understand what you're saying. Yeah. I mean, there should be no reason that someone's trying to run, a scientific and a technical, model on a simple, you know, processor on their laptop, you know, first. Yeah. Some models it'll work, but you shouldn't limit, you shouldn't.

[00:47:35] David Stacy: Not utilize the right model inputs just to get it to run. Right. I guess is what I'm saying. Right. You shouldn't

[00:47:40] David Stacy: expand your mesh

[00:47:41] Wojciech Wegrzynski: Exactly.

[00:47:41] David Stacy: validation. So it run if you do a one meter mesh, you'll be able to make a very large volume run on your laptop, but are the results valid, you know, versus if you don't have the computing power, I, I feel like the cloud service are, are pretty reasonable.

[00:47:54] David Stacy: , you know, they're usually based on, price per core hour. So if you have a four process model and it [00:48:00] takes three days to run, I mean, you're, you're looking at, I can't do the math in my head. You're looking at like under $20 us. So it's, it's not,

[00:48:07] Wojciech Wegrzynski: Yeah.

[00:48:07] David Stacy: I understand cost is a, is an issue, but it's not like these are, uh,

[00:48:12] David Stacy: killing the thing.

[00:48:13] David Stacy: Yeah.

[00:48:13] Wojciech Wegrzynski: Okay. David, David, , thank you so much, for this in interesting discussion. Thank you for your openness to talk about the processes in your company and how you deal with P B D.

[00:48:24] Wojciech Wegrzynski: Half of the audience of the podcast is scientists who, who probably never done engineering.

[00:48:29] Wojciech Wegrzynski: So I, I think it's quite refreshing for them to hear about how the engineering world, and what the issues are in here. Actually may maybe you have a message to fire scientists out there. How can they help engineers? you, can you craft a message? What comes to your head first?

[00:48:48] David Stacy: Yeah, I think, you know, we just need to continually work , on our connection , between the fields and the parties. obviously , we could leverage a lot off of each other. , but there surely are disconnects, at a very high technical level, it kind of [00:49:00] goes downhill. Right? You have your very high technical at your scientific level engineers.

[00:49:05] David Stacy: HJS firefighters. It all goes downhill. And, but we're all in the same. Like we, like we discussed we're all for the common cause, which is to improve, you know, life safety and fire protection. , to citizens across the globe and, as well as property conservation. So if we're not all in the same playing fields, it's gonna be difficult to achieve that.

[00:49:22] David Stacy: So yeah, we just all need to work together, , connect with one another, talk to each other on, on a professional level to understand where we can compliment each other , and work towards that.

[00:49:32] Wojciech Wegrzynski: Thank you so much for, for, for coming here. Thank you so much for sharing and I hope to, to see you soon.

[00:49:38] David Stacy: Absolutely. Yeah. Thank you.