From verso of the card: "Decontamination Squads, each consisting of six men, would be needed to neutralize or remove the liquid contamination caused by mustard gas or some other persistent gas on streets or buildings. . . . The picture shows some men in training . . . wearing Service Respirators . . . gum boots and full protective clothing, with hood, because their work would take them into the thick of the gas. Two are applying a paste of bleaching powder to a splashed wall."