THIS ARTICLE IS A WORK IN PROGRESS.
During the Second World War, Britain had designed eight variants of the Light Respirator from Mk. I to Mk. V. During the early post-war years, the transition from types fitted with the simplistic L2 valve holder began, in favour of those fitted with the L3 valve holder due to its inclusion of a speech transmitter, also known as a voice diaphragm. In 1951, a request for a new design of respirator was put forward to become the new service respirator, making the wartime models obsolete. This mask was the Mk. 6 Light Respirator. Serving alongside upgraded Mk. III and IIIAs from the war, the Mk. 6 became the general service respirator of the 1950s and continued service alongside one final model, the Mk. 7, into the 1960s. These masks saw service in the Korean War and the Aden Crisis, they saw service at the Chemical Defence Experimental Establishment as the "Porton-type", and later saw continued service with the Police, Fire & Rescue, and British Nuclear Fuels companies, including BNFL, until the 1990s. This would make the Light-pattern Respirator series the longest serving line of respirators in Britain.
Whilst some wartime variants of the Light Respirator were issued post war, please refer to the Respirator, Anti-Gas, Light (WWII) article for information on their issue. The history of their issue will, of course, be touched upon here, but if you wish to understand this in full detail, please refer to the predecessor page instead as this page is dedicated to the post-war designed Light Respirators, i.e. Marks 6 and 7, as well as their variants.
Disclaimer: If you use this information, please credit the user/collector Baroque4Days. This information was unknown until research/documentation began by B4D. Note that any sources used by Baroque4Days will be listed in the References & Further Reading section. Take note of this before copying any images or reusing any written content on this article. Thank you.
Design, Identification & Nomenclature
| Facepiece Designation | Rubber Mask | Valve Holder | Eyepieces | Container Mount | Headharness | Container | Sizes |
|---|---|---|---|---|---|---|---|
| Mk. 6 | L4 | L5 Mk. 1 | Mk. 3 | L1 | No. 4, Mk. 2 | L Mk. III | ES, S, N, L, EL |
| Mk. 6 L.H. | L4 LH | L5 Mk. 1 | Mk. 3 | L1 | No. 4, Mk. 2 | L Mk. III | ES, S, N, L, EL |
| Mk. 6/1 | ? | ? | ? | ? | ? | L Mk. II | ? |
| Mk. 6/2 | L4 | L5 Mk. 1 | Mk. 3 | ? | No. 4, Mk. 2* | L Mk. III | ? |
| Mk. 6 (Forehead Container) | L5 | L5 Mk. 1 | Mk. 3 | L1 | No. 4, Mk. 2 | D/8/43 | ? |
| Mk. 7 | L4 | L5 Mk. 1 (Black) | Mk. 4 | L2 | No. 4, Mk. 2 | L Mk. III | ES, S, N, L, EL |
| Mk. 7 L.H. | L4 LH | L5 Mk. 1 (Black) | Mk. 4 | L2 | No. 4, Mk. 2 | L Mk. III | ES, S, N, L, EL |
| Mk. 7/2 | L4 | L5 Mk. 1 | Mk. 4 | L2 | No. 4, Mk. 2* | L Mk. III | ? |
| Mk. 7 (Forehead Container) | L5 | L5 Mk. 1 (Black) | Mk. 4 | L2 | No. 4, Mk. 2 | D/8/43 | ? |
Components
Facepiece, Respirator
Respirator, Anti-Gas, Light, Mk. 6:
Postponed, undergoing research...
Postponed, undergoing research...
Respirator, Anti-Gas, Light, Mk. 6/2:
Postponed, undergoing research...
Respirator, Anti-Gas, Light, Mk. 7:
Postponed, undergoing research...
Respirator, Anti-Gas, Light, Mk. 7/2:
Postponed, undergoing research...
Mask, Rubber (Faceblank)
No. L4 Rubber Mask:
The rubber mask, known as the faceblank under U.S. terminology, is the central component of the respirator, the primary rubber construction itself, void of all components. The L3 rubber mask was initially introduced in 1942 as a means to increase the rubber economy by further thinning the existing L2 "No. 5 Type" mask. This was initially just a theoretical concept referred to as the "thin-type". By 1943, the mask was available in the form of the Mk. IV and V Light Respirators when the mask was trusted enough. This was mask made exclusively with the rubber blend know as GR-S (Government Rubber - Styrene), formerly known as Buna-S. This was due to a natural rubber shortage at the time.
Following the war, the existing L3 masks began to show signs of stiffening, and just 6 years after the war, were considered unusable. With the "modified light respirator", or the Mk. 6 Light Respirator, project, the L3 mould was re-used but instead of GR-S synthetic rubber, natural rubber was once again used. These masks, received a new designation and were called L4 rubber masks. As the original L3 mould was still in use, the original "L3" designation marking between the eyepieces (inside the mask) was not changed but the number "4" was printed below to provide a simple way of differentiating between the two very similar masks.
The original "L3" designation was not removed from the mould and so an additional 4 (meaning L4), was added beneath.
The L4 mask, as was the case with the L3, varies a little depending on the size of the mask. There are actually two differences between a Normal/Large and a Small sized L4 mask. Firstly, the small mask includes both a slight extension to the support fabric for the nose area, reaching up onto the two support beams. The second difference is that the small mask includes a lip at the point of the chin. It is unclear how these modifications helped but it can only be assumed that the lip was there to raise the chin higher without having to modify the overall size of the mask quite as much. However, do note that the size difference between a small and normal mask is significantly different, this modification was mostly likely an additional supportive measure.
No. L5 (Forehead Container Position) Rubber Mask:
The L5 rubber mask differs from all other Light Respirator masks in that the rubber lip used to secure the inlet valve/container mount assembly is positioned between and above the eyepieces, as opposed to being on the left or right cheek. This was likely designed as a means to remove obstruction from the cheeks, something which was a concern during the early production of the Mk. I and II Light Respirators in 1942. This type of rubber mask can be found used in Mk. 6 and 7 configurations and may have only saw use during the 1950s and 1960s nuclear weapons tests, where the masks were both tested on and used as part of the protective ensemble used by scientists at the test sites.
The inside of the rubber mask differs slightly from the L4 mask in that it does not feature any support beam between the eyepieces. This is simply due to the container mount being positioned in this area.
Holder, Valve
No. L4, Valve Holder:
The L4 Valve Holder has been confirmed to have existed but no information about it yet exists besides that it was a copy of the L3 wartime type but made of tin as opposed to steel. It was said to have had issues with peeling paint which led to the replacement of them in favour of the L5 described below. It should be noted that the L4 Valve Holder has been confirmed to have never been issued. This is undergoing extensive research by Baroque4Days.
Wartime L3 and post-war L5 Valve Holders compared
No. L5, Mk. 1, Valve Holder:
The L5 Valve Holder used following the war is identical to the L3 and only seemed to differ in its use of aluminium metal as opposed to the steel of the L3 and tin of the L4. The L5 Valve Holder was also fitted with an improved version of the speech transmitter used in the war, which incorporates a grilled-roof to help better protect the oiled-silk sheet itself.
The L5 Valve Holders seem to have some more markings compared to the wartime L3. For example, printed across the circumference of both grey and black painted versions is the designation No. 5 Mk 1 along with information on the production request and manufacturer. In addition to this, the L5 valve holder also used a grey coloured version of the L2 outlet valve, whilst the L3 used the typical tan-drab colour used throughout the wartime models.
Most metal components are created by a company known as LSL, who have been known to make eyepieces on Post-War Light A. G. Respirators as well and, sometimes, by the company P Cow & Co. This company was tasked with creating 27,000 synthetic L3 masks during the war, for the Mk. IV and V Light A. G. Respirators, and nothing else but, despite this, they were clearly re-contracted to help with the efforts to mass issue the Mk. 6 LAGR.
Head harness
No. 4, Mk. 2, Head harness:
No. 4 Mk. 2 Headharness
The final wartime component to be upgraded, or rather downgraded, was the head harness. During the early days of the Mk. IV GS Respirator, the harness in use was known as the No. 4 Mk. II and was later replaced with the better-known No. 4 Mk. III with a rubberised Mk. III tag (head-pad) and weaved straps as opposed to the Mk. II canvas tag.
Following the war, Britain reverted to the No. 4 Mk. II design and merely changed the "II" to a "2". This harness was, of course, the predecessor of the WWII Light A. G. Respirator's L2 harness and features a canvas hexagon connected to the 6 point head harness with adjustable straps, the only difference between the GS and Light type harnesses during the war being the elastic material used.
The difference between the interwar and post-war No. 4 Mk. 2 harnesses is limited to the elastics used which are much stronger than that of both the General Service and Light series. The black elasticated fabric used with the Post-War No. 4 Mk. 2 harnesses is the same material that would be used on S6 NBC Respirator. When compared to the older L2 harnesses, the newer material seems to have a much better elasticity whilst two of the wartime types were known to be prone to damage and degradation over time. Evidence of this can be obtained today in that whilst some 1944 made L2 harnesses are crumbling, No. 4 Mk. 2s made a mere 8 years later are in extremely good condition.
1960s Upgraded Harness
During the 1960s, the remaining Light Respirators in service, regardless of whether they were an Mk. 6 or 7, were fitted with unnamed, olive-green head harnesses which seem mostly identical to the 50s No. 4 Mk. 2 aside from the strap and canvas tag colour. This replacement appears to have only occurred if the original No. 4 Mk. 2 harness was damaged. This newer design better matched the straps of S6 respirator, which was, by this point, the primary Service Respirator for Britain. These later harnesses were actually made of a much more rot-resistant material.
Kit Contents
Since WWII, the Light Anti-Gas kit saw numerous changes but ultimately remained the same in principle. Following the war, there was less variation in kit contents, but nevertheless, differences between kit was still there. Some men were issued with entirely new respirators, some merely had parts changed, some were issued wartime haversacks, and some even had their wartime respirators upgraded and did not receive anything new.
Respirator Kit Examples
Mk. 6 Light Respirator kit, Baroque4Days.
Example contents of a full early 1950s Mk. 6 Light Respirator Kit:
- Respirator, A. G., Light, Mk. 6 Facepiece
- Container, Respirator, A. G., Light, Mk. III & Plugs, Sealing, Mk. 1 (OD green)
- Outfit, Anti-Dimming, Mk. 7
- Ointment, Anti-Gas, No. 6 "Temperate & Tropical Climates"
- Eyeshields, Anti-Gas, Mk. I (wartime dated, repacked post-war)
- Waste, Cotton, 1 oz
- Haversack, Respirator, Light, No. L1 Mk. 2 or 2/1
Respirator, A. G., Light, Mk. 6/1 FacepieceContainer, Respirator, A. G., Light, Mk. II & Plugs, Sealing, Mk. 1 (OD green)Outfit, Anti-Dimming, Mk. 7Ointment, Anti-Gas, No. 6 "Temperate & Tropical Climates"Eyeshields, Anti-Gas, Mk. I (wartime dated, repacked post-war)Waste, Cotton, 1 ozHaversack, Respirator, Light, No. L1 Mk. 2/1
Mk. 7 Light Respirator kit, Baroque4Days.
Example contents of a full late 1950s Mk. 7 Light Respirator Kit:
- Respirator, A. G., Light, Mk. 7 Facepiece
- Container, Respirator, A. G., Light, Mk. III & Plugs, Sealing, Mk. 1 (OD green)
- Outfit, Anti-Dimming, Mk. 7
- Ointment, Anti-Gas, No. 6 "Temperate & Tropical Climates"
- Eyeshields, Anti-Gas, Mk. I (wartime dated, repacked post-war)
- Waste, Cotton, 1 oz
- Haversack, Respirator, Light, No. L1 Mk. 2/1
Container, Respirator, Anti-Gas, Light
Container, Respirator, A. G., Light, Mk. III from the collection of Baroque4Days.
Light Container Mk. III:
The Mk. III Light Container was practically identical to the Mk. I and II in regards to its filling. It consisted of a canister body filled with a diaphragm, a cotton/fabric pad, the charcoal mix, a cotton/fabric pad, another diaphragm, another cotton/fabric pad, the resin-wool, a cotton/fabric pad, one last diaphragm and then the back plate of the container sealing it shut. However, to compensate for the increased flexibility of the rubber mask, the Light Container was made much smaller than the former two designs.
The Mk. III Light Container is roughly 89 mm (3 1/2 inches) in diameter with a weight of 226g, this compared to the 105 mm (4 1/8 inch) diameter and 333g weight of the former Mk. II Light Container, was a clear improvement. In addition to the change in dimensions, it should also be noted that the diaphragms used inside this container are noticeably different to those used in all former British Light-type Containers and the on the Mk. III General Civilian Respirator (Small Child Respirator).
Whilst L Mk. III Containers were issued alongside the Mk. 6 and 7 Light Respirator, it should be noted that L Mk. II Containers were still very much in service with the Royal Navy.
United Kingdom Atomic Energy Authority worker in Porton-type Respirator w/ D/8/43 Anti-R/A Canister.
Canister, Anti-R/A, D/8/43:
The aforementioned L5 rubber mask, the type which features a forehead-positioned canister, was not designed for use with the standard Mk. III Light Container. Instead, it was designed to be used with a particulate resin-wool canister known to Porton and UK Atomic Energy Authority staff as the D/8/43 canister. This canister was to be used in areas with low threat and could protect against nuclear fallout, as well as other dusts. The filter was entirely resin-wool and provided the same level of particulate protection as all prior light respirator containers.
More info can be found on the UKAEA Respirators page.
Haversack, Respirator, Light
Light Haversack No. L1 Mk. II/I:
Likely based on the abandoned "No. L2, Mk. 1" design mentioned in the WW2 Light Respirator page, the No. L1, Mk. II/I haversack was a general improvement to the existing No. L1, Mk. II design. Whilst there are no dimensional changes, the haversack was improved by the use of a stiffened canvas which likely helped maintain structural integrity over time. It is also possible, based on what was originally intended with the abandoned wartime design, that the new canvas was also made to be rot-proof.
These haversacks can often be found fitted with dark-green 1958-Pattern webbing straps and can also be found entirely made from this dark-green canvas, particularly during the issue of the Mk. 7 Light Respirator later into the 1950s and 60s. It should be noted that the typical green version does appear to be much brighter than that of the wartime type, which could often be considered more of a drab colour.
History & Use
Issues with Wartime Light Respirators and the need for a New Service Respirator
Postponed, undergoing research...
Design, Production and Trials of a Modified Light Respirator for the British Army
Postponed, undergoing research...
Introduction of the Mk. 6 Light Respirator & Mk. 3 Light Container into Service
Postponed, undergoing research...
Postponed, undergoing research...
Reports of Leakage with the Light Respirators from the Admiralty & the Porton Investigation
Postponed, undergoing research...
Realisation of the Deadly Design Flaws present in the Mk. 6 Light Respirator Design
Postponed, undergoing research...
The Temporary Solutions and Statements put to the War Office and the Admiralty in regards to the aforementioned Design Flaws
Postponed, undergoing research...
The Design and Production of the Second Trials version of the New Service Respirator and the Adoption of the "SR6 Mk. 1" Nomenclature
Postponed, undergoing research
The Design and Introduction of the Final Mk. 6 Light Respirator Design
Postponed, undergoing research...
Introduction of the Mk. 7 Light Respirator into Service
Postponed, undergoing research...
Nuclear Weapons Testing & the Creation of the Forehead-Canister-type Light Respirator
Postponed, undergoing research...
The Third Heat Flash Trials & Experiments with the New Special Design
Postponed, undergoing research
Finalisation of the New Service Respirator after troop trials & the Adoption of the S6 NBC Respirator
Postponed, undergoing research...
Trials with the Mk. 7 Light Respirator against the S6 NBC and M17 ABC Respirators
Postponed, undergoing research...
Review of the Mk. 6 & 7 Light Respirators
Postponed, undergoing research...
Retirement of the Light Anti-Gas Respirator from Service
Postponed, undergoing research...
Closing Statements & Observations
Postponed, undergoing research...
Manufacture & Contracts
Rubber Mask Manufacture
- Avon Rubber Co.
- Leyland & Birmingham Rubber Co.
- Stepney Tyre & Rubber Co.
Valve Holder Manufacture
- L.S.L.
Eyepieces Manufacture
- L.S.L.
Head harness Manufacture
-
Container Manufacture
- A.T.S.
- M.T.Y. (possibly something to do with Merthyr Tydfil, or the toy company METTOY who were making ammo boxes and canisters in WW2)
Facepiece Assembly
-
Light Respirator Drill
1951 Gas Training
-
1966 NBC Training
-
Repair Procedure for Light Respirators Mk. 6 & 7
CONTENT
References & Further Reading
- Windscale Example: https://www.youtube.com/watch?v=IzzeiDmwoCs
- Some photos taken from: https://gasmasksuk.wixsite.com/gasmasksuk
- The collection and general knowledge of Baroque4Days
- https://ejatlas.org/conflict/windscale-sellafield-uk
- Various scientific documents passed on to the War Office, Ministry of Defence or the Admiralty of the Royal Navy. Specifics to be referenced in time.