| CO2 | n. the chemical formula for carbon dioxide, a heavy odorless gas (CO2) formed during respiration and by the combustion or decomposition of organic substances; it is absorbed from the air by plants in photosynthesis. The formula itself, pronounced out, is often used instead of the full name, especially with reference to fire extinguishers using this gas for fire suppression; as, a CO2 extinguisher.
Syn. -- carbon dioxide, carbonic acid gas. [ WordNet 1.5 +PJC ] |
| CO2 extinguisher | a device for suppressing fire, consisting of a steel cylinder containing compressed carbon dioxide, which may be released by pressing on a handle. The release of the gas is usually accomplished through a hose attached to a funnel-shaped vent which is directed at the base of the fire, and when released, part of the carbon dioxide is chilled sufficiently to solidify into a powder. The large quantity of inert carbon dioxide released on top of a small fire is usually sufficient to exinguish the flame by excluding oxygen, and the cooling effect also helps drive the temperature of the combustible material below that required to support compustion. It is used in situations where putting water on the fire might cause undesirable damage. [ PJC ] |