Archive for May, 2015

by: Binyamin Besser

Fire Protection Code ConsultingTo be honest, fire protection engineering was not my first career choice. Before going to college I had not known that there was such a thing simply because it never crossed my mind. I fell into the major and profession due to some odd circumstances that made it more financially wise (because a bachelor’s degree costs an exorbitant amount of money in the first place). I was apprehensive coming into the profession since I had known so little about it, and since the little I learned in the beginning was just referencing books. That first year, I mostly heard about NFPA codes and standards. I do not find, literally, pounds of reference material and code books to be particularly enthralling.

I thought that I might go into the research and testing side of fire protection, being impressed and mystified by the videos and images of massive glowing flames consuming fuel in a complex test apparatus. However, as with most things, ads do not properly represent the market. Though large tests and complex, creative apparatuses exist, they are not as prevalent or accessible as one might think. I did do some testing in the Department of Fire Protection Engineering’s Fire Testing and Evaluation Center (FireTEC) and was exposed to the tedium of repetitive small testing.

After trying my hand at some testing, I thought I should look into that which I dismissed off hand, code consulting. For most of my peers, building consulting is a large part of our profession that we are not excited about doing. The task of knowing the extensive volumes of codes for the plethora of building types, occupancies, and specific area usages with their associated hazards seems like it would generate mental sloth. Since my first year in fire protection engineering, I had only some design work with the building codes in class, but became more interested in that side of the field only recently. I realized my interest was in puzzles.

Designing and fitting a building with a fire protection system is much like a puzzle. Not a 1000 piece puzzle with an obscure picture on it. Fire protection system design is a mental puzzle like Sudoku, but perhaps closer to a board game as well. The board changes for every project but the rules stay constant. The rules obviously are the codes and standards and the “game board” is the building. The rules are rigid and complex, but orderly, and the puzzle is just fitting the rules to the board. This is not the first time that professionals have used a game to solve a serious issue. The game “Foldit”, which is used to make protein structures and was played by non-scientists, has a set of rigid rules in how bonds could be formed. The game was created by scientists, but played and used by non-professionals to solve the structure of an enzyme involved in the reproduction of HIV. I am not suggesting that the fire protection profession should make an online game, but we should try to remove the mundaneness from working with fire protection codes. Code consulting and building design is such a large part of our profession, but it seems that novices in fire protection shy away from it to a degree.

There is something to be said about the draw of the more intriguing aspects of fire protection, including testing, research, and fire and explosion investigation. But we cannot forget our roots. Fire protection began with building design and the safety of people occupying those buildings. All of these aspects are aimed at the goal of safety. Testing materials allows us to determine how long it is safe for different constructions, materials, and systems to be burning. The plethora of research opportunities are used to invent new testing procedures, safety methods, and to pinpoint the science and behavior of fire. Fire and explosion investigation is used in the pursuit of justice and to insure that what has happened will not happen again.

We students tend to gravitate to the more flashy (or flashover) side of fire protection, as it can be more enticing to be entertained by mystifying fires nearly out of control, but still being managed by the experiment or apparatus that contains it. More appropriately, this representation of that side of our profession, I think, is not authentic of either the type of work done or the prevalence of that work. I feel that students are given this imagery as a “hook” to be excited, but to be better prepared for the “real world” there should be an effort to make the code consulting side more interesting to learn. I suppose time will only tell whether I am correct in my thoughts. I am, after all, only starting out.

by: Jason A. Sutula

In 1923, the Great Kantō Earthquake struck Japan with devastating force. Mountains moved, buildings crumbled, and people watched helplessly as one of the most powerful earthquakes on record stole their villages, towns, and loved ones. Adding insult to injury, the earthquake hit at midday as many people were preparing meals at the family hearth within their homes. Small fires erupted throughout the countryside and quickly spread into devastating wildfires. Firestorms and fire whirls were also recounted in tales told by the survivors. One fire whirl in particular claimed the lives of 38,000 people who had taken shelter in a building in downtown Toyko.

Fortunately, fire whirls are extremely rare. These swirling pillars of fire can be formed within naturally occurring wildfires or post-disaster fires. Certain conditions must exist for a fire whirl to develop. In particular, there must be an organized source of angular momentum to produce the swirling velocities necessary to create the whirl.

Emmons and Ying [1] were two of the earliest researchers who attempted to quantify the fire science behind the development of a fire whirl. Using a flaming pool of acetone, they spun a cylindrical screen around the resulting fire in order to produce a measurable vorticity. Two conclusions were reached. First, the radius of the fire whirl will shrink as it spins faster. Second, as the fire whirl spin increases, the temperature within the fire plume also increases.

Researchers at both the Department of Fire Protection Engineering at the University of Maryland and the Building Fire Research Laboratory at the National Institute of Standards and Technology have expanded on the foundation laid by Emmons and Ying. Battaglia, McGrattan, Rehm, and Baum [2] conducted a large-eddy numerical analysis and mapped out the flame-stretched structure of a fire whirl. Through computational fluid dynamics, they demonstrated that the rotation of the velocities surrounding the fire will structurally change the shape of the flames and bend them to its will.

In an effort not to be outdone, Assistant Professor Michael Gollner created his own fire whirl in his laboratory at the University of Maryland. The youtube video in this post was shot with a 300 frame per second high speed camera that captured a fire whirl created from a burning heptane pool situated within a specially designed compartment that added the necessary vorticity.

[1] Emmons, H.W. and Ying, S.J., Proc. 11th Int. Symp. on Combustion, Pittsburg, PA, Combustion Institute, pp 473-88, 1967.

[2] Battaglia, F., McGrattan, K., Rehm, R., and Baum, H., “Simulating Fire Whirls,” Combustion Theory Modelling, Vol. 4., pp. 123-138, 2000.

Last fall, I challenged the students in my ENFP 405/621 Structural Fire Protection engineering class in the Department of Fire Protection Engineering at the University of Maryland to compose blog postings related to their experiences in Fire Protection Engineering. This post kicks off an ongoing series of posts created by those very gifted students. Without further ado, I am pleased to present the first post in the series.

Nuclear Fire Protection, A Student Starting Off

by: Alex Chacinski

Alex C nuclear photo

Fire protection engineering sees its use in many fields. When you are new to the fire protection field, you are never really sure what it is you will be doing. Choosing a direction to take your fire protection engineering degree is difficult when all you hear is the opinions of others. As a student, all you have to go by is what you hear from professors and the occasional guest speaker. Some might say that code consulting is where the money is, or others might say fire research is the most interesting work to do. When you have minimal work experience and need that experience before you can truly carve out your own path, your best move is to take whatever job is given to you. Whether the job is something you like, or not, may not even be considered.

I found my first fire-related work in the summer of 2013 as a student intern, where I was fortunate enough to be assigned to a myriad of projects. Some work involved fire research or equipment testing, some involved modeling software, but the majority of my time was spent in the nuclear field. To give a bit of background about my experience with fire protection in the nuclear industry prior to this job, I would say I had as much experience as fire has experience burning under water. Regardless, I started the nuclear work: reviewing drawings, plant procedures, and creating massive spreadsheets to house data. It turns out my early work was part of a probabilistic risk assessment (PRA).  The plant data was being put into models to calculate the probability of a fire event seriously affecting the plant. Of course, nobody wants another nuclear plant fire crisis (we are looking at you Brown’s Ferry!). Before long, I was examining major plant equipment, measuring zones of influence, looking at spatial separations from conduits and cable trays, and calculating the fire severity in the event that some piece of equipment would ignite. I was looking through equipment databases and detailed drawings, learning everything I could about what I was doing. After some time though, I realized that I really had no idea what my work actually meant. I was focused on my spreadsheets and data crunching, and yet I did not even know what a nuclear power plant looked like in real life. What I did know however, was that I enjoyed the work and liked the path my early career was taking.

Fortunately, I was soon given the opportunity to do onsite PRA walk-downs. I was finally able to put a face to the name, or in this case, a visual to a number. After a quick flight and a night spent in a hotel, the team and I found ourselves at a nuclear plant. After some long security procedures, we were on our way inside to collect the information we needed to run our models. I quickly learned that nuclear plants were essentially huge machine jungles made of steel and concrete. Cable trays and conduits tangled through all the rooms like well-kept vines, and loud machines roared from room to room. Despite the overwhelming atmosphere, I was quick to learn. The equipment I was running fire calculations on finally had a face. I could now see how an electrical fire could start in an electrical panel. I could sense how the fire may be able to jump to a nearby cable tray. That fire could then burn the wiring to the main control room, and soon the plant could be having a reactor meltdown. Everything started to make sense. The work I was doing seemed to finally have purpose. I was far from a nuclear fire protection expert, but I was learning quickly and enjoying the experience.

Since then, I have worked on other nuclear jobs. Some also PRA related and some concerned with the transition from Appendix R requirements to NFPA 805 requirements. I have learned a lot about the nuclear field and feel comfortable doing that kind of work. I even prefer it over some other traditional fire protection engineer work. I am still a student, but now I feel like I have some good work experience under my belt. Going through school and starting a career is a long journey that everyone takes on their own. It is hard to know where you will end up or what work you will be doing. I certainly had no idea where I was going or that I would appreciate nuclear fire protection engineering work. Now, I am happy to say I found a corner in fire protection engineering that I enjoy. For any other young engineers, my advice is to keep trying new things. Who knows what part of fire protection engineering you will enjoy until you get the opportunity to try it?