NIR-Compliant
(Near InfraRed)
Your combat gear should meet various requirements, including FR (Fire-Retardant) and NIR-Compliant (Near InfraRed).
FR means that your equipment will not catch fire and/or melt on you when exposed to a source of heat, including IED (Improvised Explosive Devices), missiles, strikes from drones, or just finding yourself in something that has been set on fire, like a tank or vehicle (armored or not).
NIR-Compliance involves Near-InfraRed (NIR) Signature Management Technology that is used to prevent detection of individuals by NIR Image Converters. These photocathode devices do not detect temperatures, but rather infrared radiation variances. NIR-compliant equipment uses a special fabric/treatment/conditioning that allows individuals to appear at the same radiation level as the surrounding terrain, thus making them more difficult to detect.
In practice, when it comes to FR, you shall only use clothing that is certified FR, or that is at least 80% (preferably more) wool. Including, and maybe especially, base layers. This means that stuff like Under Armour, for some reasons popular for a time with service members, is absolutely out, as it is made of synthetic fabrics, which will not only disrupt your endocrine system lowering your testosterone levels and sperm count, but also will melt on your skin when exposed to an open flame or even high source of heat.
When it comes to NIR-compliance, it means that gear that is not Berry-compliant or at least produced in Europe or Canada is very unlikely to be NIR-compliant. This includes cheap stuff you get on Amazon, made in China, or pretty much the entire 5.11 line. On the other hand, gear such as Crye Precision G3 Combat pants and shirts, Arc’teryx LEAF Alpha jackets and pants, or even Mystery Ranch Jump Komodo pack are NIR-compliant. This means that you will not stand out in the field and will even completely blend in your surroundings, depending on camo pattern and environment.
The video at https://rumble.com/v26nu5o-nowhere-to-run-to-nowhere-to-hide.htmlshows that sadly, some Ukrainian forces did not get the memo.