[ad_1]
Gas masks protect against dangerous bacteria, viruses, chemicals and airborne poisons. They use filtration, absorption, and chemical neutralization to purify air. They were refined during WWI and are available to the public, but long-term exposure requires a self-contained breathing system.
Gas masks are close-fitting devices designed to protect the wearer from exposure to dangerous bacteria, viruses, chemicals, and airborne poisons. Most gas masks seal the wearer’s nose and mouth to protect the airways, but some models include goggles and full hoods. Gas masks are not to be confused with oxygen masks or diving masks, which import fresh air from a closed tank. Gas masks filter outside air as it is, without adding fresh breathing gases.
No inventor can lay claim to the gas mask’s original design, although many sources give great credit to an African American soldier working during World War I. Soldiers exposed to airborne poisons often urinated on a cloth and covered their mouths and noses with it. The ammonia in urine would chemically neutralize the chlorine gases commonly used on the battlefield during World War I. Further refinements created gas masks capable of filtering or neutralizing more advanced nerve agents such as mustard gas, but the use of chemical warfare had declined significantly by the start of World War II. Soldiers routinely discarded their gas masks once the battlefield was secured.
Gas masks protect the wearer through three separate methods. Many pollutants have particles larger than oxygen and nitrogen atoms, so filtration is the first line of defense. Most gas masks use a replaceable filter with an extremely fine mesh to physically block incoming particles such as smoke or virus-laden dust. The main problem with such a filtration system is that any mesh tight enough to block microscopic particles will also restrict the flow of clean air. The wearer may not feel enough available breathing air with the filter in place.
Another means of purifying the air in gas masks is absorption. Vaporized liquid poisons and germs can be removed from the user’s airways by absorbent chemicals such as activated charcoal. These absorbent chemicals can be stored in a container under the breathing chamber or soaked into the filter. The major drawback of the sorption method is the limited number of poisonous gases that would be attracted to the chemicals. These types of gas masks would be very useful in a factory environment where the pollutant was a known entity.
The final air purification method used in gas masks is chemical neutralization. This is what WW1 soldiers were doing with their homemade ammonia masks. A canister containing a chemical or gas is attached under the faceplate, and the fumes interact with the incoming poison, rendering it chemically neutral, or at least harmless to breathing. This method is widely used in situations where chemical warfare is possible. The main disadvantage is the somewhat unpleasant atmosphere created by the neutralizing agent.
Gas masks are available to the general public through medical supply stores, military surplus operations, and specialty retailers. Workers who may be exposed to hazardous fumes are advised to wear some form of gas mask to protect their respiratory systems. For long-term exposure situations, however, a self-contained breathing system with a fresh air supply may be more beneficial.
[ad_2]