It is a 'bright' colour for use in darker spaces like vehicle interiors where there are small or no windows, etc. Basically so you can see well inside with limited ambient light from outside, or from a limited numer of interior lights.
It replaced the white interior of US armour in the mid-60s, supposedly because it worked as well as white but wasn't quite as bright, easier on the eyes, didn't show dirt as badly but still showed things like hydraulic fluid leaks, and is somewhat easier to maintain.
I was playing with a BRDM a few days ago, their interior is dark green up to mid hull, white from there up. It was noticably not as light inside as the all-bright-painted-interior vehicles like the V100.
I recall a similar seafoam colour in the cargo area of C130s. It was a sadistic swine who made the mesh troop seats a fluorescent red. Those of you who have ridden in those planes with high density troop seating know what I mean. Looking though a couple of layers of swaying bright red webbing at a blue-green background is positively nauseating!
Cheers
Pics- BRDM interior
