Gas Mask

A gas mask is a mask used to protect the wearer from airborne pollutants and toxic gases. The mask forms a sealed cover over the nose and mouth, but may also cover the eyes and other vulnerable soft tissues on the face. Most gas masks are also respirators, though the word gas mask is often used to refer to military equipment (such as a field protective mask). The mask only protects the wearer from digesting, inhaling, and contact through the eyes, as most agents affect through eye contact.

History
Much of early gas mask development was made during the first world war, primarily due to the high use of chemical weapons by both sides. The first proper gas masks came in the form of what was known as "smoke hoods"; closed hoods with a piece of clear plastic for seeing. While these provided limited protection from poison gas, it was an inefficient and often ineffective form of protection. Not soon after, proper gas masks made from leather and aluminum were made, using activated charcoal to absorb poison gases. The charcoal was held within a filter on the end of a long tube, which pulled air into the mask when the wearer inhaled.

In 1943 the first modern gas mask was created, made from plastic and rubber-like materials. The primary difference between this and the older model was that the new design lacked a long tube; having the filter directly attached to the mouth of the mask. As years went on, many different models of gas mask were developed, especially during the Cold War.

Use
Gas masks are airtight, and worn snugly on the face. Most masks only cover the face, but some wrap around the entire head. A filter that is screwed on to the mouthpiece of the mask absorbs the pollutants from all air inhaled by the wearer, and a small flap on the underside of the mask allows for exhaled air to safely escape without putting the wearer at risk. Most gas masks have only one singular filter, while others contain two.

Gas masks protect from most airborne poisons, several airborne pathogens, and from most amounts of radioactive particles.