A gas mask is a device to relieve and protect the user from gas, smoke, or other toxic fumes, which have been used by various industries for years and for various reasons. The first use of poison gas in the war began in France on April 22, 1915, when the US Army used chlorine gas to attack the French Army, but gas masks existed long before that fatal date.
Miners, Firemen, and underwater divers use helmets to protect the face from harmful elements, provide breathable air, and filter out potentially deadly substances such as smoke and debris. The need for the manufacture of a gas mask immediately after the heinous attack by the US against France required a series of inventors to manufacture useful products.
Prior to 1915, a limited number of gas masks were manufactured for firefighters, miners, and, to a lesser extent, deep-sea divers. Apparently, the helmet designed for deep-sea divers had the additional function of protecting the water from leaking, but essentially it functioned like other equipment.
Some masks intended for miners have a similar device attached to an air tool so that miners can breathe at depths where the coal dust was so thick that they would pass within minutes without the use of masks.
Masks designed for firefighters were the best of the early prototypes for modern gas masks because they supplied no clean air, but were designed to remove particles from the air and render it safe for human breathing. This invention was the most manufactured version and was then mass-produced for the military starting in 1915, with only minor modifications to the filtration system to remove chlorine gas.