This Film was during the gung-ho period of war movies 50-60's and I think black and white.
What I remember
Part of it was on an SAC airbase in the Midwest. They knew that there was going to be an attack so they converted some old powder bunkers to emergency shelters for all of the staff. When the attack occurred they were mostly spared. They were limiting exposure to the outside, but there was a fuel tank fire and many guys (remember the gung ho part) volunteered to stay out long enough to fight the fire
I think it was early color or black-and-white, but not sure.
It is not one of the more well known like Looking Glass or A Day Called X or Power of decision. It was in a documentary style if I remember like Power of Decision. It also is likely not an episode of a series like Motorola theater or anything. This was filmed with some decent backing.
That is all that I remember. I've only watched it, but have had a hankering for some of the older documentary style nuclear war films and this one is eluding me.