On July 19, 1916, during World War I, the bodies of soldiers were scattered around British artillery positions in Frimel, northern France, following a German gas attack.

 　During World War I, on July 19, 1916, in the northern French town of Froomel, the bodies of British soldiers were scattered around a British artillery battery following a German gas attack. The German army launched a gas attack on the British artillery battery in Froomel, believed to have been using phosgene gas.By 8 a.m. on July 20, 1916, the Battle of Frelow ended, with Australian forces suffering 5,533 casualties. British forces suffered 1,547 casualties, while German forces had over 1,000 casualties.

　Phosgene and diphosgene gases were used as substitutes for chlorine gas. They had a musty, hay-like odor and irritated the nose and throat, causing coughing, difficulty breathing, and suffocation. The deadly aspect of phosgene gas was its delayed effect, which could take up to 48 hours to manifest, potentially leading to death by fluid buildup in the lungs.The first use of phosgene and diphosgene gas by the German army against British forces in the Battle of Ypres in December 1915 ultimately accounted for approximately 85% of gas-related deaths in World War I. Gas masks designed to protect against the effects of the gas were ineffective against phosgene gas, which was colorless and fired from high-powered shells. Detecting the gas and putting on a gas mask often took too long.

　  During World War I, approximately 91,000 people died from gas attacks. Over 1.2 million were injured by exposure to gas. Injuries persisted long after the war ended, with many dying later from respiratory diseases. Poison gas did not significantly alter the course of the war in 1918. It accounted for approximately 1% of all casualties in World War I. Its use was banned under the 1925 Geneva Gas Protocol.