The Mk 3 NBC suit we looked at last month was very good for its day, but in the mid 1980s the British Army decided to update the design to accompany the new S10 respirator it was introducing. The Mk 3 was only available in olive green fabric, so a small batch of Mk3a suits were produced in DPM (we will look at an example of these at a later date). Whilst this was a definite improvement, the smock still needed to be pulled on over the head and it was felt that having a conventional zipped fastening up the front was a better design. This led to the next major version of the NBC suit, the Mk 4 and tonight we are looking at the smock:Whilst the camouflage fabric and front opening are the most obvious changes to the suit, perhaps more importantly was an improved fabric that was more effective at repelling chemical agents. The outer layer of the smock has a silicon treatment that helps waterproof the fabric from rain and allows liquid agents to spread over the surface rather than sinking in, aiding evaporation. A fluorocarbon finish was also applied which acts as an oil repellent, increasing its effectiveness against liquid agents. The suits were also designed to be fire retardant. Despite all this protection, the suit remains breathable preventing the wearer from overheating. When it was introduced this was one of the most effective NBC suits in the world and it remains in use to this day, underlining the general strength of its design.
Returning to the Mk 4 smock then, we can see that it opens up the front, with a metal zip that is covered by a Velcro flap:A piece of elastic is sewn around the edge of the hood to ensure a tight face seal with the respirator:Velcro tabs allow the sleeves to be adjusted:And the waist:A pair of large angled bellows pockets are sewn over each breast:The stitching of these pockets only penetrates the first layer of fabric so it doesn’t compromise the suit. Another small pocket is fitted to one sleeve to carry pens etc.:A label is sewn into the collar giving sizing:In all six different NSN codes are allocated to the DPM smock based on sizing:
160/092 Extra Small 8415-99-130-6921
170/100 Small 8415-99-130-6922
180/100 Medium 8415-99-130-6923
190/108 Large 8415-99-130-6924
200/116 Extra Large 8415-99-130-6940
Special Fitting 8415-99-130-6925
The underside of the label indicates that it was made by Remploy:This suit was also produced in desert DPM fabric and at some point I will pick up one of those to accompany this example.