1 00:00:01,920 --> 00:00:07,080 Speaker 1: Welcome to brain Stuff production of iHeart Radio. Hey brain Stuff, 2 00:00:07,120 --> 00:00:09,800 Speaker 1: I'm Lauren Vogelbaum, and this is a classic episode from 3 00:00:09,800 --> 00:00:13,360 Speaker 1: our previous host, Christian Sager. The fire extinguisher is an 4 00:00:13,400 --> 00:00:16,480 Speaker 1: amazing piece of simple equipment that can help you smother 5 00:00:16,520 --> 00:00:18,440 Speaker 1: of fire should it happen to get a little out 6 00:00:18,440 --> 00:00:22,080 Speaker 1: of control. In this episode, we explain how they work 7 00:00:22,480 --> 00:00:27,640 Speaker 1: and what kinds work for what kinds of fires. Hey, 8 00:00:27,680 --> 00:00:31,480 Speaker 1: brain Stuff, it's Christian Sager. Let's talk about fire. Fire 9 00:00:31,560 --> 00:00:34,880 Speaker 1: is the result of a chemical combustion reaction, typically between 10 00:00:34,880 --> 00:00:38,600 Speaker 1: oxygen and some sort of fuel like wood or gasoline. 11 00:00:38,920 --> 00:00:41,520 Speaker 1: For the reaction to occur, the fuel has to reach 12 00:00:41,560 --> 00:00:45,760 Speaker 1: its ignition temperature. For wood, that's about five hundred degrees 13 00:00:45,800 --> 00:00:49,400 Speaker 1: fahrenheit or two hundred and sixty degrees celsius. The heat 14 00:00:49,560 --> 00:00:53,880 Speaker 1: decomposes some of the woods cellulose, and the decomposed stuff 15 00:00:54,000 --> 00:00:58,800 Speaker 1: is released as volatile gases, like a compound of hydrogen, carbon, 16 00:00:58,920 --> 00:01:02,360 Speaker 1: and oxygen. When the gas is hot enough, its molecules 17 00:01:02,400 --> 00:01:06,440 Speaker 1: break apart. The atoms recombine with the oxygen to form water, 18 00:01:06,680 --> 00:01:10,679 Speaker 1: carbon dioxide, and other products. The heat keeps the fuel 19 00:01:10,760 --> 00:01:13,959 Speaker 1: at the ignition temperature, so it keeps burning as long 20 00:01:14,000 --> 00:01:17,080 Speaker 1: as there is fuel and oxygen. So there you have it. 21 00:01:17,200 --> 00:01:21,200 Speaker 1: Fire the result of extreme heat, oxygen and fuel. But 22 00:01:21,319 --> 00:01:25,880 Speaker 1: what about fire extinguishers They remove at least one of 23 00:01:25,920 --> 00:01:30,560 Speaker 1: these elements from the equation. Fire extinguishers are metal cylinders 24 00:01:30,600 --> 00:01:34,080 Speaker 1: filled with water or smothering material, and when you depress 25 00:01:34,120 --> 00:01:36,840 Speaker 1: a lever at the top, the material is expelled by 26 00:01:36,920 --> 00:01:40,319 Speaker 1: high pressure, kind of like an aerosol. Can imagine a 27 00:01:40,360 --> 00:01:45,160 Speaker 1: fire extinguisher cut in half. Okay, that plastic siphon tube 28 00:01:45,280 --> 00:01:48,760 Speaker 1: leads from the bottom of the fire suppressant reservoir to 29 00:01:48,880 --> 00:01:52,600 Speaker 1: the top of the extinguisher. A spring mounted valve blocks 30 00:01:52,640 --> 00:01:55,800 Speaker 1: the passageway from the siphon to the nozzle, and at 31 00:01:55,800 --> 00:01:58,840 Speaker 1: the top of the cylinder there is a smaller cylinder 32 00:01:58,920 --> 00:02:03,360 Speaker 1: filled with compressed gas liquid carbon dioxide for example. A 33 00:02:03,440 --> 00:02:07,520 Speaker 1: release valve keeps the compressed gas from escaping. When you 34 00:02:07,560 --> 00:02:10,359 Speaker 1: pull out the safety pin and depress the operating lever, 35 00:02:10,520 --> 00:02:13,880 Speaker 1: it pushes on an actuating rod. The rod presses the 36 00:02:13,919 --> 00:02:16,840 Speaker 1: spring mounted valve down to open up the passage to 37 00:02:16,880 --> 00:02:19,920 Speaker 1: the nozzle. The bottom of the actuating rod has a 38 00:02:20,000 --> 00:02:23,760 Speaker 1: sharp point which pierces the gas cylinder. Release valve. The 39 00:02:23,800 --> 00:02:28,760 Speaker 1: compressed gas escapes applying downward pressure on the fire suppressant material. 40 00:02:29,200 --> 00:02:32,240 Speaker 1: This drives the material up the siphon and out the nozzle. 41 00:02:32,480 --> 00:02:35,040 Speaker 1: The proper way to use the extinguisher is to aim 42 00:02:35,080 --> 00:02:38,560 Speaker 1: it directly at the fuel, not the flames, and spray 43 00:02:38,639 --> 00:02:43,040 Speaker 1: in a sweeping motion. There are three main types of extinguisher. 44 00:02:43,360 --> 00:02:46,880 Speaker 1: A water extinguisher can put out things like burning wood, paper, 45 00:02:47,120 --> 00:02:50,960 Speaker 1: or cardboard, but it doesn't work well on electrical fires 46 00:02:51,080 --> 00:02:56,040 Speaker 1: or fires involving inflammable liquids. In an electrical fire, water 47 00:02:56,320 --> 00:03:00,680 Speaker 1: may conduct the current, which could electrocute you. Water will 48 00:03:00,760 --> 00:03:04,919 Speaker 1: only spread an inflammable liquid, making the fire worse. Then 49 00:03:05,360 --> 00:03:08,920 Speaker 1: there's the carbon dioxide extinguisher. The CEO two is kept 50 00:03:08,960 --> 00:03:12,640 Speaker 1: in a pressurized liquid form. When the container is opened, 51 00:03:12,800 --> 00:03:16,320 Speaker 1: the CO two forms a gas. This gas is heavier 52 00:03:16,320 --> 00:03:19,760 Speaker 1: than oxygen, so it deplaces the oxygen surrounding the fuel. 53 00:03:20,160 --> 00:03:24,399 Speaker 1: This extinguisher is common in restaurants because it won't contaminate 54 00:03:24,440 --> 00:03:29,280 Speaker 1: cooking equipment or food. The most popular extinguisher material is 55 00:03:29,320 --> 00:03:34,359 Speaker 1: the dry chemical extinguisher. These cylinders contain foam or powder, 56 00:03:34,520 --> 00:03:38,840 Speaker 1: typically made of sodium bi carbonate, also known as baking 57 00:03:38,880 --> 00:03:45,320 Speaker 1: soda potassium bicarbonate or mono ammonium phosphate. Baking soda starts 58 00:03:45,360 --> 00:03:48,760 Speaker 1: to decompose at only a hundred and fifty eight degrees 59 00:03:48,800 --> 00:03:53,160 Speaker 1: fahrenheit or seventy degrees celsius, and when it decomposes, it 60 00:03:53,360 --> 00:03:56,880 Speaker 1: releases c O two. The CEO two, along with the 61 00:03:56,920 --> 00:04:01,000 Speaker 1: insulation of the foam, smothers fire. The best way to 62 00:04:01,040 --> 00:04:04,280 Speaker 1: tell which fire extinguisher you have and which fires it's 63 00:04:04,320 --> 00:04:06,960 Speaker 1: best suited to fight is to look at the rating. 64 00:04:07,480 --> 00:04:10,840 Speaker 1: All fire extinguishers have an A, B or C rating. 65 00:04:11,200 --> 00:04:16,400 Speaker 1: A Class A fire extinguisher works best against fires involving paper, wood, plastic, 66 00:04:16,440 --> 00:04:19,720 Speaker 1: and textiles. A Class B fire extinguisher can put out 67 00:04:19,800 --> 00:04:24,200 Speaker 1: flammable liquid fires, you know, things like cooking oil, gasoline, paint, 68 00:04:24,360 --> 00:04:28,120 Speaker 1: or oil, and a Class C extinguisher is your go 69 00:04:28,240 --> 00:04:32,520 Speaker 1: to for live electrical fires. Each extinguisher will have a 70 00:04:32,680 --> 00:04:35,599 Speaker 1: number by the letter indicating the size of the fire 71 00:04:35,680 --> 00:04:39,640 Speaker 1: that it can tackle. But please be careful. Most fire 72 00:04:39,640 --> 00:04:43,480 Speaker 1: extinguishers contain a small amount of suppressant. You can use 73 00:04:43,520 --> 00:04:46,760 Speaker 1: it up in seconds. That's why they're only effective on 74 00:04:46,960 --> 00:04:50,560 Speaker 1: relatively small fires. To put out a bigger fire, you 75 00:04:50,640 --> 00:04:54,000 Speaker 1: need more equipment. Like a fire engine as well as 76 00:04:54,040 --> 00:04:56,960 Speaker 1: trained professionals, but for the blazes that can pop up 77 00:04:56,960 --> 00:05:00,440 Speaker 1: in your house, a fire extinguisher can be a life sapor. 78 00:05:06,920 --> 00:05:09,200 Speaker 1: Today's episode was written by Ben Boland and produced by 79 00:05:09,200 --> 00:05:11,719 Speaker 1: Tyler Clang. For more on this and lots of other topics, 80 00:05:11,839 --> 00:05:14,599 Speaker 1: visit how stuffworks dot com. Brain Stuff is a production 81 00:05:14,640 --> 00:05:17,040 Speaker 1: of I Heart Radio. For more podcasts on my heart Radio, 82 00:05:17,120 --> 00:05:19,640 Speaker 1: visit the i heart Radio app, Apple Podcasts, or wherever 83 00:05:19,680 --> 00:05:21,000 Speaker 1: you listen to your favorite shows.