Discussion in 'Weapons, Equipment & Rations' started by Tartan_Terrier, Nov 19, 2005.

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  1. Hi there,
    I've been wondering if someone can explain this concept a bit. I've heard that most non-issue items are not IRR, and therefore appear to glow when seen through night vision equipment.

    I've also heard that comercial detergent makes IRR items non-IRR (though from my own experience I don't believe this). From what I've seen, it appears to be mostly synthetic materials which have this problem as I've seen waterproofs and fleece tops which appear very bright through NVGs.

    The concept of things being Infra Red Reflective, would in my opinion make them appear brighter (i.e. reflecting light). So why is it that non-IRR things don't appear dark through NVGs?
  2. The reason you can still see IRR treated (issue) items theough NVGs is that the NVGs enhance available light sources and utilise IR light as available. So the image you are seeing of issue kit is that of ambiant light and a lower level of IR reflection than non treated kit.

    If you look at things like softie jackets or wooly hats with NVG kit and an IR source they will appear bright white.

    (i think)
  3. I assume you're referring to near-IR systems (through which we perceive the world as being 'green' - due to the phosphourus in the phototube) as opposed to far-IR - or TI.

    Through a TI EO device, a non-radiating body (or someone wearing a highly effective thermal cover) will appear effectively 'invisible'. Near-IR systems work by reflecting ambient light (as admirably explained above), so the only way your men would appear 'black' would be if they were wearing light absorbtive clothing - in effect, stealth uniform, as it would be absorbing the wavelengths of light.

    Edited to add: The terms 'near' and 'far' IR are broadly relative to 1-2 microns for near IR II systems; and 3-5 and 8-14 for far TI systems.
  4. Back in the 80,s I remember someone saying that you wern,t allowed to wash your combats yourself due to IRR becomeing ineffective. You was supposed to hand them into the QM,s for special cleaning & treatment. Yeah right !!! when we were on exersise for 6 months of the year during the BAOR days a 3 to 4 week wait for combats was,nt that practical. I don,t think anybody actually went through that route.

    Regards LT.
  5. That's absolutely correct.

    You shouldn't wash CS95 at all, and certainly not use starch or other solvents on them.

    Going off-topic for 2 ticks, you also aren't supposed to 'bull' CAB either...or sew badges all over your kit.
  6. It's some years since I did the STANOC course (is it even called that any more?) but, as I remember it, the IRR problem was to do with active IR illumination systems used with IR goggles - which are pretty much obsolete these days and have been since image intensifiers came in, never mind TI. Anyway, apparently there is a big difference in the degree of IR reflectivity of urban and rural backgrounds, with rural being much higher. The idea of IRR clothing was to mimic the reflectivity of the most likely operational background - which, at the time was, again, if I remember correctly, the rural one.

    I don't think IRR really has any relevance to detection by more modern methods, except that I know an IR light source is very easily detected with an image intensifier, so I guess that a highly IR reflective thing would be quite easy to see against a low IR reflective background, if there were much in the way of IR light about. That ought to mean that IRR kit would not be the thing to wear in an urban environment - supposing I haven't got the whole thing the wrong way round, which is quite likely.
  7. Since on one patrol we had to wear ir lightsticks so our snipers wouldnt shoot us .(Not sure what system they had that could hit
    in a pitch black rainy night 2km away but not willingy to experiment ) Is irr really an issuse nowadays :?: .
    And yes someone did say my lightstick dosen't seem to work :lol:
  8. Commercial washing detergents generally use a chemical that glows in UV light, you won't notice it until you mix some powder and water and look at it in the dark with a UV light, it then glows like a barsteward! It's there to make your "whites whiter" hence it's not idea for washing your combats!

    I believe soap flakes are free of it and a suitable alternative, although don't sue me if you get shot because I only said "I believe", it ain't gospel.
  9. Oh damn! You'll start all the WP religionista off again!
  10. Through NVGs my Pikeytex daysack sticks out like a bulldog's wotsits, while my issue kit remains dark. Though I think ingrained dirt is fairly effective at reducing IR reflection, so the less you wash your kit the better. Obviously I'm only talking about webbing.
  11. Thanks for the info guys.

    Just for the record it was image intensifiers I meant, as unfortunately thermal imagers are as yet not issued to my unit.....could be nice though!
  14. I dont know about special treatments but the dhobi in Kosovo used to add a nice diesel fragrance to all my washing....including me shreddies. They always seemed dirtier than when I put them in.
  15. Someone mention phosphourus?

    Darth, since you seem to know, does ironing CS95 affect its IRR properties, or is it just the starch?