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Phenate Hexamine Helmet

Name: Phenate Hexamine Helmet

Model: N/A

Filter Type: Impregnated Fabric Hood

Application: Military

From May 1915 until the summer of the following year the primary means of protection used by the British against gas were the Helmet Respirators. During this period of just over a year, the helmet respirators evolved from the very simple Hypo Hood which comprised of a single layer of fabric with a single mica eyepiece to the more advanced, although still rather crude Phenate-Hexamine Goggles (PHG) Helmet which featured two layers of fabric, an exhale valve and integrated goggles which sealed against the wearers face.

In between these two very different types of Helmet were the Phenate (P), and Phenate-Hexamine (PH) Helmets. These improved upon the earlier Hypo Hoods by being made out of two layers of fabric impregnated with sodium phenate which offered a good degree of protection against phosgene and hydrogen cyanide. These helmets also featured screw on coated glass eyepieces which were less prone to damage compared to the mica eyepiece of the Hypo Hood, and an exhale valve meant that exhaled air didn't have to pass back through the fabric. This resulted in reducing the build of carbon dioxide inside the helmet considerably, and it also helped reduce the dimming of the eyepieces. With regards to appearance, the P and PH Helmets are more or less identical, the main difference between the two was in the chemical solution they were dipped in. The P Helmets were discovered to provide very little protection against higher concentrations of phosgene, experiments in order to improve their protective capabilities eventually led to the P Helmets being treated with a new chemical solution which now contained hexamine. In January 1916, the P Helmets began to be re-impregnated with this new chemical solution. Thus, the P Helmets became PH Helmets. More often than not to denote the impregnation with the new solution, PH Helmets featured the marking "PH" followed by a lot number, this also makes differentiating the two much easier. Upon the introduction of the Small Box Respirator (SBR) in August 1916, the PH Helmet continued to be produced and issued right up until the end of the war,  they were to be used only as a secondary line of defence. There are some discrepancies with regards to the numbers of the P and PH Helmets manufactured, but the generally accepted figures are around nine million P Helmets, and around fourteen million PH Helmets were manufactured by the close of the war. These are both absolutely staggering numbers to say the least.

The PH Helmet as worn, being demonstrated by a Portuguese soldier. They were kept as a reserve mask following the introduction of the Small Box Respirator in August 2016. Image courtesy of  Mr Carlos Ramos.

Despite the huge number of Helmet Respiators manufactured, the vest majority were disposed of after becoming surplus to requirements at the close of the First World War. However, many appear to have avoided this fate as a result of being kept by the soldiers they were issued to as apposed to being handed back, and today, due to their iconic status many reside in private collections and museums all over the world.

This particular hood, which was manufactured in 1917, was actually sent from Britain to allied Portugal during the First World War, and there it remained for just shy of a century until September 2016 when it made it's journey back to the UK.

Below is some data about the PH Helmet held in the GasMasksUK Collection, and a selection of detailed photographs including a page from the British 1918 Defence Against Gas Manual.

 

Date - Facepiece: 1917                                                                       Manufacturer/Markings - Facepiece: PH02  S&N (Stamped)  82 (Pencil)

           Filter: N/A                                                                                                                          Filter: N/A

           Harness: N/A                                                                                                                    Harness: N/A

           Eyepieces: Nil                                                                                                                   Eyepieces: Nil

           Exhale Assembly: Nil                                                                                                        Exhale Assembly: Nil

Front view of the PH Helmet showing the eyepieces and the external portion of the mouthpiece to which the flapper type exhale valve would have been fitted. Note the pencilled "84" on the bottom right, likely from the manufacturing process.

Rear view of the PH Helmet, showing both the stamped markings; "PH02" and "S&N 1917" and the distinctive front flap which extends lower than the rear portion of the helmet. This flap is only found on what were manufactured as PH Helmets and not P Helmets which were later re-impregnated with the PH Solution.

Internal view of the front of the PH Helmet, showing the lining and the internal part of the eyepieces and the mouthpiece which still has the rubber covering on the tip.

Internal view of the rear of the PH Helmet, note the faint stripes on the lining. These are a characteristic of many PH Helmets.

The PH Helmet as described in the 1918 Defence Against Gas Manual, describing how to wear, maintain and store the Helmet in its carrier.

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