Why do not use water to set fire when extinguished?
Wood caught fire, can use water to throw out the fire. That is common knowledge that everyone knows. But, if the pan of grease catches fire or the gas tank, the fuel tank catches fire, it is necessary not to pour water on it, because then the water not only can not put out the fire, but instead makes the fire bigger. can put out the fire on wood, can’t put out the fire in the fat pan?
This is because combustion requires oxygen and certain temperatures. When burning wood, pouring water into the burning wood can completely isolate the wood’s contact with the air, which can lower the temperature of the wood. So the fire was immediately extinguished. When the fat pan catches fire, because the density (density) of fat is smaller than water, if splashing water into the fat pan, the water immediately sinks under the grease layer, pushing the grease layer to the surface, just okay with no separation. gas, does not work to reduce the temperature, so water does not extinguish the fire in the grease pan. If you do not skillfully, the fat can also flow out of the pan, spread outside, increase the contact area of the fat with the air, the bigger the fire.
So when the fat pan catches fire, what measures must be taken to extinguish it? The most direct method is to immediately cover the pan, making the fat and air isolate completely, the fire will also turn off immediately.
If the gas tank catches fire, firefighters often use a fire extinguisher (containing fire extinguishing foam) to put out the fire. This is because this tank spews a large amount of carbon dioxide. Carbon dioxide is not both self-igniting, nor aiding fire, and heavier than air, it will cover the fuel tank very quickly, making gasoline and air completely isolated, thereby promptly extinguishing the fire.
Photo by PiConsti