The need for a sealed face mask to protect against the inhalation of smoke and airborne toxins became apparent with the development of underground mining in the eighteenth century. A crude respirator was invented by the Prussian naturalist Alexander von Humboldt in 1799 while he was working as a mining engineer. Other designs included Garratt Morgan's "Safety Hood and Smoke Protector," developed in 1912, consisted of a cotton hood with two hoses reaching down to the floor, where cleaner air would often be found.
But the crucial imperative in the development of an effective gas mask was the use of poison gas, especially chlorine. This gas was used for the first time in World War I by the German Army at the Second Battle of Ypres in April 1915. Initial attempts to counteract the chlorine gas using cotton mouth pads and absorbent hoods proved either ineffective or cumbersome and thousands of soldiers perished.
In 1915, the Russian chemist Nikolay Zelinsky (1861-1953) invented the coal gas mask, which used a carbon filter to absorb the chlorine. The design was quickly adopted by the British, French, and Russian armies and has continued to play a crucial part in counteracting chemical warfare.
Carbon filters work by absorbing airborne particles and gases. Carbon powder is especially effective because of its very high surface area. Later gas masks were designed to protect against biological agents such as viruses and bacteria and radioactive fallout. However, masks alone are insufficient against many of these agents.
