Building 103 (Decontamination Centre)

Gas Decontamination Building at RAF Duxford

This is a gas decontamination building constructed in 1939 by the Air Ministry's Directorate of Works and Buildings, following drawing number 6224/37. It was designed to protect personnel against chemical weapons in the event of gas attack.

The building is a rectangular block measuring 88 feet by 32 feet (26.9 metres by 9.7 metres). The walls are constructed of brickwork laid in Flemish bond. A distinctive feature of the design is the earth revetment that rises to approximately half the building's height on all sides, protecting the lower brickwork and supporting heavy steel beams that carry a flat asphalted concrete roof. The roof structure is double-skinned concrete throughout, with part of the roof—above the water storage tanks—raised as a hipped roof section, also asphalted. The upper walls rise to a flush coped parapet, with a square external stack serving the boiler room at the south end.

The exterior at ground level is cement-rendered, and the earth revetment slopes at its natural angle of repose, grassed over the top for stability and visual integration into the landscape. Two U-plan protective structures project from the west side, with raked walls aligned to the earth slope. Two narrow passageways through the revetment provide access to the main entrances.

The interior is accessed via two protected entries on the long west side. The building is divided by brick partitions into distinct functional areas. Entry leads through a short passageway to a reception and undressing area. Lockers set into the external walls can be accessed from outside via a protected walkway around the north end. From the undressing room, air locks provide access to the large bleaching room equipped with showers. The south half of the building contains storage for clean clothing and a large dressing room, with exit again through an air lock. Beyond these areas are rooms for boiler and air-conditioning plant. The interior retains its original layout.

The decontamination process followed a specific protocol. Personnel would enter through a foot-bath of bleach solution, guided by guard rails or covered entrances if blinded by exposure to mustard gas. In the undressing area, clothing was removed and deposited through special openings where it was collected in bins for de-cleansing by boiling. An air lock then provided access to the bleaching room where showers were typically arranged in two groups with a space between them, allowing personnel to wet themselves, apply soap, and rinse. Eyes were washed in warm water. After thorough washing, the antidote to mustard gas—a specially prepared bleach paste—would be rubbed into affected areas and removed within two minutes. Fresh clothing could then be put on in the dressing and waiting area before exit through another air lock. The plant equipment supplied clean, filtered air and maintained raised internal air pressure to seal the building against gas infiltration. All doors had rubber seals, and the undressing room contained pressure stabilisers on the external wall to release pressure as necessary.

This building is one of a pair of identical decontamination centres at Duxford, both designed to the standard form for the RAF's Expansion Period of the 1930s. A second centre for wounded personnel, identical in design, is attached to the Station Sick Quarters. The buildings were built in response to the threat of gas attack, greatly feared after World War One. Although the Geneva Gas Protocol of 1925 outlawed the use of gas in warfare—to which both Britain and Germany were signatories—the British Government, aware of how agreements could be broken during hostilities, developed gas weapons and protective measures. These decontamination buildings were designed to treat personnel exposed to all types of gases developed during World War One: lachrymatory agents, respiratory agents, and blister agents such as mustard gas.

Mustard gas was particularly dangerous because it had only a faint garlic smell, and symptoms were not always apparent until some time after exposure. In liquid or vapour form, it could be absorbed by the skin without detection. Once irritation was noticed, the agent had already penetrated the skin and begun causing serious damage. Metal detection plates coated with paint that changed colour when exposed to mustard gas were positioned at intervals along pathways. The critical treatment window was twenty minutes from initial contamination; if exposed clothing could be removed, thorough washing completed, and fresh clothing put on within this time, serious injury could be avoided. One of mustard gas's effects was blindness, which is why the protective entrance arrangements were essential.

Duxford represents the finest and best-preserved example of a fighter base typical of the period up to 1945 in Britain, with an exceptionally complete group of First World War technical buildings and technical and domestic buildings representative of both inter-war RAF Expansion Periods. The site has important associations with the Battle of Britain and the American fighter support for the Eighth Air Force.