Thursday, March 15, 2012

Richardson Citizen's Fire Academy


Class 17, Week 3



We had dinner from Golden Chick. Four of us that had done Ride-Outs over the past week reported on our experiences. We were introduced to Captain Younger from Station 5, and he talked about their Engine #3 that was on site. It's an E-One HP78 Quint. Loaded with equipment and full tanks, it weighs about 63000 pounds. The model number indicates that the aerial ladder has a 78' reach from the ground. It's capable of pumping between 2000-2500 gallons per minute. It carries a 500 gallon water tank and a 15 gallon tank of class A foam. Equipment includes 1 3/4" and 3" ground hose and 1000' feet of 5" hose (for hydrant hookup). It also is stocked with a full set of ground ladders (16', 24' and 35') plus "A" frame ladders. It also has a smaller tank of Class B foam used for hydrocarbons such as gasoline.



We learned that fire requires four things: fuel, oxygen, heat, and a chemical reaction. Fires can be extinguished by removing any of those four things. For example, forest and brush fires often are left to burn out, but roadways are used and trenches are dug to create borders, removing fuel. Putting a lid on a pan in a kitchen fire removes oxygen. Water not only removes heat, but slows the chemical reaction. Fog and foam can also be used, and we learned that foam has many advantages. It permeates porous materials like wood very well. It "coats" very well, so can create an excellent defensive barrier (e.g. coat the wall of the house next door to keep a house fire from spreading). It is also very lightweight. Water weighs 8.33 pounds per gallon and is incompressible. Filling an attic with foam will prevent a fire from spreading through that space, but also dramatically decreases the possibility of a roof collapse, which is very common when water is sprayed into an attic. A mixture of 0.2% to 0.5% of foam is all that's needed, and that's often mixed with air to create a larger foam surface area. Also, in more northern climates, foam is more resistant to freezing than water. We learned that moving a 5" hose full of water takes a lot of strength. Most modern fire engines are now equipped with CAFS (Compressed Air Foam Systems).



We all went out to the equipment room and found bunker gear to fit us. Pants, coat, boots, helmet, and gloves. A full set of gear weighs about 40 pounds, and keeps you really warm. Even though it was 70 degrees outside and we weren't doing anything very strenuous, it got really hot later. Imagine fighting a fire when it's 100 degrees outside. Most of the gear was hand-me-down stuff, and some of the pieces had names embroidered in them (I even recognized a couple names), so they duct-taped the coats and pants with our names so we could locate them easily next time.



Then we went outside to learn about pumps and hoses. We split into two groups. My group went to the quint to learn how to control the outriggers and the aerial ladder and its spray controls. We learned how to tap a hydrant and run a hose to the pumper. Then learned how to switch from the onboard tank to the city water supply and direct it to the aerial monitor. You have to extend, lower and adjust the outriggers before the aerial ladder can be moved. You have to rotate, then raise, then extend the aerial ladder to avoid undue wear and tear. We all got to climb on top of the quint and learn to work the controls.



Then we switched vehicles and went to the engine to get a chance to work the ground hoses. We each got a turn aiming and adjusting a smaller hose and a larger one while seated.

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