The gas mask as we know it today evolved from inventions over time that were intended for use by deep sea divers, firefighters and mine workers. A popular misconception about the gas mask was that it was invented by Garrett A. Morgan in 1914. Morgans invention didnt resemble anything remotely like todays mask and was simply a hood with a breathing tube that hung to the floor so a firefighter could draw breath from the lower, cleaner layers of air while fighting a fire. It was later adapted for mine rescues where the tubes could be manipulated to avoid flooded mine tunnels or gas filled pockets. The question of who invented the gas mask is to this day not easily answered.
WW1 definitely started the mass production of modern gas masks designed to protect soldiers from chemical attack. Without WW1 and the use of chlorine and mustard gas as a weapon by the German Army, gas masks would have not have taken up such a prominent place in the history of the world.
Here is a list of some of the inventions and patents issued to a long line of gas mask inventors throughout history. In 1848 a US Patent was issued to one Lewis P. Haslett for a device constructed to exclude smoke and other solid particles from the breathed air and gas mask manufacturing began in earnest in the United States. In 1854 Scottish chemist John Stenhouse invented a simple mask that used charcoal to filter noxious gases. In 1871 and 1874 two British inventors produced devices that removed solid particles and noxious gases from the air using a full hood over the head and tubes connected to a canister of slightly pressurized oxygen. In 1914 Garrett Morgan invented a device that gained national prominence when it was used to rescue 32 mineworkers trapped far beneath the surface in flooded mining caverns.
All of these devices came together on that fateful day in 1915 in France when chemical weapons were used on a large scale for the first time. From that moment on, the gas mask was no longer a safety device just for firefighters and mine workers. From that moment on the gas mask was a crucial element in the fight for freedom. Who invented the gas mask? You might say it was necessity after all, she is the mother of all invention.