Gas warfare

Chemical weapons are used on the battlefield for the first time.

A cloud of gas rolls over Flanders Fields. Terrified soldiers stumble and fall, gasping for air and choking on the poisonous mist that burns their lungs. Others run for their lives in a desperate attempt to escape. Mass panic and 2500 casualties ensue.

The Germans have just released 1600 tonnes of chlorine gas during the Second Battle of Ypres (22 April–25 May 1915) – the first use of lethal chemical weapons on the Western Front. The chaos allows the Germans to penetrate the Allied line to a depth of 3km in places.

The Allies respond with their own chemical warfare units, and a mini arms race begins. Both sides rush to develop defensive measures to protect their men. The most important of these is the gas mask, introduced in 1916. Even so, gas remains one of the truly horrific weapons of World War I.

Photos & objects

Smoke pots released to simulate a gas attack for training in Palestine.National Army Museum of New Zealand: 7588

Members of the 6th Australian Sanitary Section training in the ‘PH helmet’ gas mask, 1 May 1916.Australian War Memorial: C01316

Gas mask inspection of a Wellington Regiment, 15 April 1918.Henry Armytage Bradley Sanders, AWMM: PH-ALB-419-H593

NZ troops checking gas masks, 15 April 1918.Henry Armytage Bradley Sanders, AWMM: PH-ALB-419-H595

German gas mask, pre -1915.AWMM: W0026. © Auckland Museum CC BY