In 1914 a chemist called Fritz Haber offered his knowledge to the German Army. He soon began experimenting with chlorine gas ...

The First World War was the first-time poison gas was used on a large scale during war. The gas could affect someone in just a few minutes so protective masks were given to all soldiers.

Demand for gas masks is skyrocketing ... possible to prepare for that." Masks have long been used as a protection for diseases and in times of turmoil. World War I soldiers used respirators ...