I'm not sure IR goggles have been implemented yet.
The last I heard, you were supposed to equip them in your hand and use the "scan" ability to see through walls, but I'm not sure if that even works. Wearing them on your head supposedly does nothing (mind you, I heard this a long time ago).
Also - when you say NVG, do you mean IR? Because while NVG uses infra-red the goggles in this game are different judging from the scan-see through light objects thing (which doesn't even work, both in the game and in real life I believe)