The S6 military respirator was developed in the 1950s by the Defence Science and Technology Laboratory, Porton Down and was manufactured by the Birmingham & Leyland Rubber Company. The S6 gained notoriety when seen being used by Britain’s Special Air Service (SAS) during the widely and thoroughly documented Iranian Embassy Siege of 1980.



Margaret Thatcher stands between some SAS members with S6 masks on their faces

The S6 gas mask was an enormous leap in technology for the British gas mask industry and for the Military. The features of the S6 include the very innovative inflatable air seal around the inside of the face piece along the edges (extending approximately one inch around the entirety of the face piece). It also had an earlier design of an oral-nasal cup that was built into the mold of the mask, not a separate piece extending from the interior of the face piece extending back to cover the nose and mouth. It features a “six point” semi-elastic head harness made of a rugged fabric with easily adjustable metal buckles. Weight (in carrier?) 1.22kg.

The mask provides an excellent field of vision using larger eyepieces in the shape of half rounded rectangles. Additionally, the S6 is made of a soft, durable black rubber. The mask uses a “side loading” filter to the left of the mask, making it much easier and more natural to shoulder a firearm for right-handed soldiers. A version of the mask was made to accommodate left-handed shooters, where the filter input was simply switched to the right side. It was very much liked by the British military for its comfort and very low breathing resistance.

The mask was used from the mid 1950s to 1986 when the S10 respirator was introduced and put into production and used widely throughout the British Military.


In the early 80s, the armed forces of Turkey adopted the S6 as the SR10, and subsequently added a drinking tube to the design, designating their version of this mask as the SR-10ST.