Brake Third coach No. 3307 converted into a mobile cleansing unit, 1941
The fear of gas attack was of paramount concern during World War II, as demonstrated by the mass issuing of gas masks prior to the outbreak of war in 1939. One of the responsibilities of the ARP services was to lead the decontamination and cleansing process in the event of such an attack. Mobile cleansing units were made available to the ARP service to clean people who had been exposed to gas attack, and in July 1941 the GWR converted Brake Third coach No. 3307 into an ARP Cleansing Unit for this purpose. The van was equipped with an air lock leading to an undressing room, showers, and further along the vehicle, a dressing room stocked with fresh clothing. As can be seen in this photograph, the windows were completely blacked out and they were also made to be blast proof. This was one of 47 such units converted by the major railway companies, which were stationed at strategic locations for immediate dispatch to any station or rail depot where they were needed.