Final answer:
During WWI, soldiers endured the discomfort of poorly fitting gas masks due to the threat of poison gas attacks. Adjusting or removing these masks meant potential exposure to deadly gases, so soldiers trained to wear them correctly and sometimes altered their facial hair for a better seal. Continued efforts were made to refine the design of gas masks to improve both comfort and effectiveness.
Step-by-step explanation:
During World War I, soldiers had to deal with the harsh realities of trench warfare, including the threat of poison gas attacks. The gas masks provided were often uncomfortable and could chafe the skin, but adjusting or removing them could mean exposure to deadly chemicals like chlorine, mustard gas, or phosgene.
To deal with the discomfort without compromising their safety, soldiers had to undergo training to ensure their masks were properly fitted before heading into potential gas attack scenarios. They also had to resist the urge to remove or adjust the mask in the field, enduring discomfort to avoid the far worse effects of the gas.
To minimize the problem, changes to personal grooming were sometimes necessary. As shown in the case of Adolf Hitler, soldiers sometimes altered their facial hair, like trimming mustaches, to ensure a better seal was maintained around the edges of the gas mask. Furthermore, efforts to improve the gas mask designs continued throughout the war, to make them as comfortable and as effective as possible.