Phenate-Hexamine (PH) Hood
The PH hood (or 'helmet' as it was officially known) was the second anti-gas hood issued to British troops during the Great War. Prior to this a much simpler hood with no valve was issued. Prior to that, in the very early days of gas warfare, a simple pair of goggles and a gauze fasemask were given to the troops. The PH hood proved to be quite effective and was the standard anti-gas equipment by mid 1916. Its drawbacks were that it was uncomfortable and that the eyepieces tended to move from in front of the wearer's eyes and also to steam up. The hood was impregnated with neutralizing chemicals which cancelled out poison gases. The soldier would breathe through the material of the hood itself. He breathed out through a copper tube in his mouth attached to a red, one way flutter-valve. The hood was kept in a waterproof rubber case (known as the 'inner bag') which was held in a cloth bag slung over the soldier's shoulder. The bag had three tin buttons on its strap to allow for some adjustment in length. Even when the PH hood was not standard issue during most of the latter years of the war, photographs still show soldiers wearing the bags to keep other belongings in. The below mask and bag is a good quality reproduction, which are available from a number of sources.