Hazmat suits are civilian versions.

What about the military version NBC suit?

http://wikipedia.org/wiki/MOPP

Would make the best gear in the wasteland next to power armor.

Aren't elite ranger armors serving this function? Well, maybe not, but they look pretty similar (and badass).

MOPP suits look incredibly badass in every way. Would love to see something like this in a FO game. Perhaps there's a mod for this armour?

I thought NPC ranger suits came from riot gear.

This is a full MOPP suit

http://www.ico.aha.ru/jj/peosoldier.army.mil/photos/JSLIST.jpg

They do, but isn't mask having the same properties as this from hazmat suit? Honest question, I don't know.

Besides, I believe that ranger armor is already enough badass to be second only to remnants power armor.

Well IMO, in a wasteland, I'd worry about practicality before style.

And where I wrote about style? Ranger armor is very practical - helmet gives you low light optics, a dual infrared and LED light and gas mask and probably also protects you just like MOPP mask. Of course, it also offers some protection in combat.

A Military version could also be and overcoat with hood, wader pants with suspenders, and gas mask that is worn over the combat armor or other as needed.

It could be similar to the yellow version except in Olive Drab or other necessary coloration like flat grey or camouflage patterned for say woodland.

Or it could be like my homebrew armor for my Tabletop RPG group which appears as if the player is wearing combat armor and helmet over an Olive Drab Radiation suit with a -1 to Agility/Perception checks for the player... haven't decided yet on which yet.