The origin of the modern protective respirator can be traced back to the Second World War during which the Light Anti Gas Respirator, or Lightweight Respirator was developed in the UK. It was originally intended for and issued to those involved in operations in which the more conventional Service Respirator could prove to be a problem because of its size and weight. Although basic in comparison to the masks of the present era, the Light Anti Gas Respirator introduced many features that would become standard on respirators used by the armed forces of many countries for years to come. Which in my eyes makes it worthy of a thread of its own, along with it being one of my favourite designs in militaria as a whole.
At the moment I am studying the development of the Lightweight Respirator as the early stages of design and the experimental ages are rather unclear to say the least. After a few visits to various places in the UK including the National Archives, and some defence establishments I should hopefully have a lot more information to add to this thread. For now though, I am going to simply detail the various masks that all fall under Lightweight Respirator name, and how to differentiate them. I'm also not too sure on whether each of the variations have different designations as the differences between some of them are very slight, so any names I give them are more collectors terms than anything else.
Unfortunately due to me living away from home for long periods of time due to work commitments, I won't be able to provide any additional photos of most of the masks for quite some time. However, if you require some, or further details I'll write myself a reminder.
This is the one of the early production models of the Lightweight Respirator from, featuring the early pattern of exhale valve/voicemitter assembly, the centre of which is a convex shape which sticks out slightly. The design went through several changes in order to make it more compatible with the No.7 Hand Microphone which was apparently deemed sufficient enough which meant that a special microphone for the Lightweight Respirator wasn't made.
This is a slightly later model, using another of the several variations in face piece design. This particular one shares similarities with the British Civilian Duty Respirator, most noticeably the triangular shape in-between the bottom of the eyepieces. This model features the second pattern of exhale valve/voicemitter assembly, again to make compatibility with the No.7 Hand Microphone easier. Note the cork bung in the filter, another is fitted to the inside making it water tight.
More often than not, the variations featuring the second pattern of exhale valve/voicemitter assembly are Dutch post war re-issued masks, as shown above. These are very common on the collectors market and can be easily identified by the fact they are in usually immaculate condition and their markings. Finding one that isn't post war re-issued is rather difficult indeed.
This variation came about a few months later and was again an attempt to make the mask more compatible with the No.7 Hand Microphone, in this case the microphones "trumpet" could actually be pushed on to the threaded protruding part of the exhale valve/voicemitter assembly. Why it was threaded I don't know, but it is more than likely that if a microphone was developed it could be easily fitted to the mask. I'm also not too sure whether this pattern was intended for use by radio operators only, or if it was intended to be standard issue. The rare in comparison to the second pattern, so personally I am leaning towards the idea of them being only issued to those who required them.
Another variation with the threaded protrusion on the exhale valve/voicemitter assembly. Although similar in appearance, this one is internally different as can be seen if you look through the holes on the protrusion. Once I get the opportunity to take an in depth look at both masks and do a comparison, I'll update this thread with the new information.
Here is the post war model, very similar in design to the wartime mask on which it was based. The only real significant differences (excluding the markings) are the head harness, the colour of tape used to cover the wire holding the components together and the type of filter. Like the Danish re-issue masks, these are also fairly common on the collectors market, and can be found in unissued condition.
This isn't really a variation in the standard design, it is more of an adaptation intended for special purposes. In its carrier there was a document which described the filter as "Porton Type" and listed a large number of chemical and biological agents that this type of filter could protect against. Based on that, I suspect that this mask more than likely came from the famous, and somewhat infamous Porton Down facility in Wiltshire.
Another oddball variation of the Lightweight Respirator is this post war dated mask featuring both Avon (on the mask) and L&B R Co (on the filter) markings. Instead of being fitted with a filter using the 60mm same thread as its predecessors, it has an adaptor glued in place which allows a standard NATO 40mm filter to be fitted. It also has an individual serial number engraved into the exhale valve/voicemitter assembly which corresponds with a number stamped onto the carrier that came with it. I personally think it was a trials mask used for assessing the 40mm threaded filter design which became a standard for all masks used by NATO countries until very recently.
Same as the above mask, but featuring a different type of eyepiece retaining rings. Again, it is engraved with an individual serial number which matches the one on its carrier.
I hope that this is useful and that the different types of the Lightweight Respirator is a little bit more clearer with me pointing it out as the changes between variations is very subtle and something most wouldn't even notice, which is why my parents still tell me that they "all look the bloody same"!
Also, below are front views of the two Wartime third pattern exhale valve/voicemitter assemblies. The internal differences can be seen through the holes on the front.