All UL talks about is water application. They refuse to look at the use of additives like surfactants that make water more effective at extinguishing fires. If Lars is pushing UL solutions then he's talking the same game that everyone else has been talking since the caveman threw the first bucket of water at a fire. While the rest of the industrilized world uses chemistry and physics to develop new ways of building the world around us you would think that those that consider themselves to be at the cutting edge would fold some of the chemistry and physics into their approach to firefighting beyond what we did as cavemen to put them out. Chief Hughes Battalion 1 (retired) Chicago FD
Water cools heat not smoke. Heat represents the physics of a fire while smoke and invisible fire gasses represent the chemistry of a fire. Smoke is particulate matter produced in a fire made thousands of chemical compounds many of which are petroleum based making smoke hydrophobic (water repellant). Per ULFSRI research only 5% to 10% of water applied to a fire contributes to extinguishment. When we add a chemical surfactant found in wetting agents water becomes 3 to 5 times more effective at extinguishing fire as compared to plain untreated water. Fight the heat with water, yes, but to get at the chemistry of the fire (smoke and fire gasses) you need to add chemistry to water. Chief Hughes Battalion 1 (retired) Chicago FD
I don't get a particular piece: at around 48:30 there is the statement that if you are able to suppress the fire we would be able to start ventilating in order start searching for victims. Since we only suppressed (and not extinguish!) the fire, aren't we simply providing the fire with more oxygen? Or do we keep suppressing the fire from outside until we are able to reach and extinguish it (after rescue?).
Very very good arguments and demonstrations. I am very thankful for your time and effort. I am, however, now😊 questioning everything I know and have done lol 😆 😅
As a Swedish firefighter I really learned a lot from these three well spent hours of talking. Nozzle knowledge and training and interior fire tactics is quite a huge piece of the puzzle that's missing in the Swedish fire service, and we have a lot to learn from this kind of videos. Thank you!
In the US has big flow on the hose. This put out the fire faster. Instead control the environment is a good point but it is a syntoms not the daeses they manege the environment with the stream but the realife is the K point in the Europe don't has this number and the environment have to accurately manage.
Transitional attack for a Swedish 🇸🇪 FireNerd? 😆 That is American 🇺🇸. What happened to "Smoke Cooling?" You're now SvenskAmerikaner FireNerd. Best regards from the Philippines 🇵🇭. Semper Paratus!
As always great discussion. Have been following ULFSRI since the Governor's Island Research. This man is a gift to the fire service. Concepts and Tactics should be taught as a whole. Big fan of Steve and Lars. Different countries with different perspective and approach in a civil discourse is a gem. Continue the great work. Semper Paratus! Best regards from the Philippines 🇵🇭
Spännande grejer! Vi skulle behöva få igång övningseldandet av hus igen för att bli duktiga på det här. Det är i dagsläget väldigt svårt att hitta verklighetstrogna sätt att öva och testa det. Nåt att klura på!
Water's volume expants while been heated. I ve learned that 1 lt water becomes 1700 lts of steam in100 c degrees and increases more in higher temperatures. So pressure in close room rises either with straight or fog. My question is: all the hot gases that come back to us is because of the negative pressure that is produced from using fog stream, from the overpressure that we produce adding water, or both? I like your job. Keep up. 👍👍👍
In theory water expands 1700 times when converted to steam at 100 degrees. True. But that only applies if the energy is taken from solids, not gases. If the energy is taken from gases the total volume is instead decreased. In reality we always hit both surfaces and gases so it will be a mix. Probably an initial under pressure followed by over pressure when the gases are cooled (which is a fast process). If the objective is under pressure, reduce flow to below 5 seconds in normal residential rooms. Or limit water to only hit the gases (practically very hard). Or over apply water to cool everything down below vaporization temperatures. Massive cooling with high flow. If we entrain air from outside the room that is different as we supply new air into the room creating an over pressure. That is a probably much faster and a larger factor in that case, and thus more important to consider. Use a straight stream when in doubt.
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Tackar! Det var en tankeväckande lektion! Hälsningar från andra sidan Östersjön.
"The fire service is one of the few opportunities you have to go into a field with very little education and training and have a respected profession" . This statement is so true and it resonates with me. I'm not from this country, english is not my first language and only went to high school. I am as far as you can be from being an academic. BUT, not being an academic does not prevent me from nerding out and learning as much as I can. This job is the best thing that could've happen to me. Great conversation and very educational as usual.
Hej Lars Tack för väldigt intressanta filmer och resonemang. En fundering efter denna del 3. Du lägger mycket vikt vid koordineringen av håltagningen. Samtidigt så visade du tidigare i filmen att man kan ha bra effekt med dimspikar eller liknande på stora volymer i en läckande uthuskonstruktion. Min fråga är, om det är svårt att skrapa fram resurser för denna koordinerade håltagning, flera dyra värmekameror osv. Kan man inte, åtminstone i teorin ha framgång med att fortsätta köra dimspikarna och jobba med ett hål i taget? Eller blir temperaturen för låg i utrymmet för att hålla den magiska vattenhalten?
Jag presenterar vad jag tror är en ideal lösning. Om man inte kan skapa hålen samtidigt så visst kan det funka att skapa dem ett åt gången. Men risken är större att det blir för låg halt vattenånga kvar för att hålla nere branden undet tiden. Och att syre tillförs utan möjlighet till kylning av ytorna där branden utvecklas. Har man dimspikar etc som täcker större delar av volymen går det säkert bra ändå. Problemet blir väll om man dessutom inte har bra täckning med vattendimman så stora volymer får chansen att utvecklas då hålen skapas.
One thing to add is that in a lot of situations the straight stream can be used in bursts just like fog. A 2 second burst will give a good impact on the ceiling or walls and you wont have tons of water everywhere. Burst, shut down advance, repeat...
Lars and James, thank you for sharing this conversation. I serve in the A-B corner of the US where the primary firefighting influence is from Los Angeles. The historical perspective presented by James was "rad." Thank you for the educational references to better understand fire dynamics.
Hello, very good video. You are right, what you say is also my experience. I've been working with the full jet and dynamic jet pipe guidance for a long time. thanks for the great video.
Could you give me a hint where I can find Ricardos research regarding gas cooling? Or maybe post a link on facebook when the english version is published? Great talk as always
