Which type of relationship carbon dioxide fire extinguisher prevents air from feeding the fire?
A carbon dioxide (CO2) fire extinguisher prevents air from feeding a fire through a process called asphyxiation. The mechanism behind this is based on displacing oxygen, which is necessary for fire to sustain, in the surrounding environment. CO2 extinguishers work by releasing a highly pressurized stream of carbon dioxide gas into the fire, creating a cloud that covers the flames. Here's how the process works:
1. Check the fire extinguisher: First, make sure you have a CO2 fire extinguisher, which is typically identifiable by its black horn-like nozzle and the presence of a high-pressure gauge.
2. Aim at the base of the fire: Point the nozzle of the CO2 extinguisher at the base of the flames, rather than aiming it directly at the top of the fire.
3. Pull the pin: CO2 fire extinguishers typically have a safety pin securing the handle. You need to remove this pin to activate the extinguisher.
4. Squeeze the handle: Firmly grasp the handle and squeeze it to release the CO2 gas from the extinguisher. This action activates the gas discharge mechanism.
5. Sweep side to side: Using a sweeping motion, move the nozzle from side to side across the base of the fire. This helps to distribute the carbon dioxide gas efficiently and extinguish the flames.
6. Assess the situation: Once the fire is extinguished, carefully evaluate the area to make sure there are no reigniting flames or signs of danger. Keep in mind that CO2 fire extinguishers should only be used on Class B (flammable liquids and gases) and Class C (electrical) fires.
It is important to note that CO2 extinguishers should not be used on Class A fires (common combustible materials like wood or paper) since these fires require a different kind of extinguisher, such as water or foam-based ones.
By discharging carbon dioxide gas, which is denser than air, the extinguisher displaces oxygen present around the fire. This reduction in oxygen concentration suffocates the fire, preventing it from gaining fuel and ultimately leading to its extinguishment.