During World War I, the Ministry of Munitions built a filling factory for artillery shells on the site, which was farmland commandeered by the military for its closeness to Avonmouth docks and to the site of the National Spelter Company’s chemical works in St Andrew’s Road, Avonmouth, later the National Smelting Company. At Chittening, Nobel Explosives filled shells with chloropicrin, derived industrially from picric acid. In defiance of the Hague Convention on weapons, the German army used mustard gas (dichloroethyl sulphide) against Allied troops on the Eastern and Western Fronts in 1917, and the British minister of munitions, Winston Churchill, ordered supplies to be manufactured in Britain for use in retaliation. Having first used captured German gas in late 1917, and then gas produced at factories in Manchester and Runcorn, from June 1918 three filling factories, at Banbury, ROF Rotherwas at Hereford, and Chittening, were supplied with freshly manufactured mustard gas by the National Smelting Company. By November 1918, with unskilled female labour, Chittening had produced 85,424 mustard gas shells, but at a human cost of 1213 notified cases of associated illness, including at least two deaths which were later attributed to influenza. The story of the women who filled the shells at such great personal risk has been told in the stage play Gas Girls. Rather late in the day, a small hospital and surgery were opened on the site around the time of the Armistice.