BY JASON HOEVELMANN
One day while on duty, I was throwing away some newspapers in the recyclables container when I noticed four five-gallon containers that once contained foam. One of our engines had had a vehicle fire with fuel burning; the fire was stubborn, so they eventually used some foam. Now, exactly how they used 40 gallons of foam is another topic, but these containers were discarded without any other thought about their uses.
Typically, I likely would not have noticed them, but my combination department uses them for storing large lengths of utility rope on our boats and dive trailer. We clean the containers out and just stuff the rope into the bucket, and we carry the rope by the buckle handle. It has proven to be an easy way to get the rope from the apparatus into rugged areas. I am not saying that we are being “green” at the same time, but we always have a little foam, maybe eight to 10 ounces left at the container bottom, that we have to clean out before we can put the rope into the buckets.
I started pulling the buckets out with the intention of showing my deputy chief and asking him whether we should put rope in them or just take them home to use around the house. He had a different suggestion that ended up becoming a training session on a Sunday morning.
We discussed the amount of foam left in the bucket and decided it would be interesting to see how it would work in a water fire extinguisher, or “water can.” We pulled off the water extinguishers, emptied them, and then filled the mostly empty foam buckets with water and mixed the small amount of foam with the water.
We conducted tests to determine the capability of the solution. We needed to burn something and then put out the fire with water and then with the foam-filled extinguisher.
We used as our burn props some old boxes that were lying around. In addition, we added two burn pans with flammable and combustible fuels to see how our extinguisher handled a Class B fire. The fuel in the pans was no more than a half-inch to an inch deep.
THE TESTS
Our first test was just to discharge the fire extinguisher to see the expelled solution. The nozzle of the extinguisher could be considered a smooth-bore nozzle on a miniature scale. So, there was some doubt if the foam would aspirate out with the water. What we found was that since we pressurized the extinguisher with air, the result was a stream with foam in it. You really couldn’t tell until it hit an object, but it certainly was foam-laden water.
The initial evolution was just a pan of fuel and some cardboard boxes. The firefighter, a rookie, started to apply the product in the extinguisher onto the fuel in the pan (photos 1-3). Initially, it looked like it was going to have the same effect as water on the liquids fire, but soon we saw the blanket of foam snuff out the fire (photo 4). The first test was successful. The box was extinguished quietly.
| (1) Photos by author. |
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| (3) |
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We decided we wanted to get some video and a side-by-side comparison between the water-only extinguisher and the foam extinguisher. The real question was if there was any real difference or hindrance in using this foam instead of only water on Class A fires. We refilled and set up two pans and two piles of cardboard for the next fire in our back parking lot.
We tested the pan fires first. We lit a pan and used the water-only extinguisher.
What we saw was no surprise: The fire flashed and roared but did not come close to going out (photo 5). Next, we used a water/foam mixture. When we aimed it at the burning liquid, the fire flashed again, just as it had with the water can.
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We aimed the stream to the rear of the pan and banked the product off the side and the fire. Success again.
Next were the boxes. There was no discernable difference between the water extinguisher and the foam extinguisher.
Both fires went out in about the same time and without any problem, but there was a small, thin blanket of foam on the majority of the cardboard that had just been extinguished.
After the fires were extinguished, we started to refill and discuss our thoughts about our little project. We were all convinced that it could be beneficial to have the foam in the water extinguisher.
It was also the consensus that using the leftover foam from the buckets was using our resources to their fullest, and it was easy to mix. We filled the remainder of our water extinguishers, labeled the other buckets that we had mixed for the “water cans,” and relayed our experiment to the oncoming crew the next morning.
Obviously, this was far from scientific, but it was fairly accurate for practical purposes. If you really wanted to figure out the exact mix, I guess you could. Our objectives were to use an extra resource that was available and to show that it was useful and easy to use without causing harm or necessitating a big changeover. This experiment showed that some different thinking can lead to some fun and valuable training. I honestly couldn’t tell you the last time I participated as a student in fire extinguisher training. I had taught several classes, but this was fun and probably much-needed practice.
Our experience was that we were sure that we had all heard of this before, but we just didn’t remember the idea until that day.
Sometimes, we just need some cue to make us re-remember something that is simple and could also be valuable. After all, isn’t that what training and practice are all about? I encourage you to experiment (safely) and train on the ideas you have. You never know what you might find out.
Editor’s note: Check with your extinguisher manufacturer for your equipment’s capability with the use of foam.
JASON HOEVELMANN is a deputy chief/fire marshal with the Sullivan (MO) Fire Protection District, a combination department, and a career firefighter/paramedic with the Florissant Valley Fire Protection District in North St. Louis County. His experience spans more than 20 years; he has been an instructor for more than 15 years. He is an adjunct instructor for the St. Louis County Fire Academy and a state-certified fire officer II. He has an associate degree in paramedic science and a bachelor’s degree in fire service administration from Eastern Oregon University. He is a state advocate for the Everyone Goes Home® initiative.
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