How did chemical weapons affect soldiers on the Western Front?

On the Western Front during World War I, the introduction of chemical weapons profoundly impacted soldiers, causing widespread fear, confusion, and high casualties among those who were unprepared.12

When chemical agents like chlorine gas were first deployed, they created wind-borne clouds that forced defenders into chaotic flight. These choking agents, which also included phosgene, functioned by causing fluids to build up in the lungs, leading to death through asphyxiation or oxygen deficiency. Phosgene was particularly lethal, accounting for approximately 80 percent of all chemical-related deaths during the conflict.13

To counter these threats, soldiers were forced to adopt protective measures, most notably the gas mask. While these masks were essential for survival, their use—along with other protective gear—imposed significant burdens on combatants. Prolonged use of such equipment often led to fatigue, heat stress, and disorientation, and it could decrease a unit's conventional combat effectiveness by 25 percent or more. Consequently, soldiers faced a constant, difficult trade-off between maintaining protection against toxic exposure and preserving their ability to fight effectively in the field.12