The events that I recall are people being blinded as they look towards the explosion, and then crawling around the ground not knowing where they are, looters trying to get food and mobbing supply trucks getting shot by policemen as well as whole buildings swamped in fire being tackled by firemen. The story also contains radiation sickness and the whole of society collapsing.
I was going to order it on DVD, but it is quite expensive, as it seems to be quite rare. I'm going to try and get one, as I think it will really help me with the atmosphere I'm aiming for in my project.
The whole film can be watched on Youtube here: http://www.youtube.com/user/nevermore1000#p/u/4/58NmAzQzRjk
If you watch Part 1; at 1:20 through it, the policeman is driving through Chatham, passed where the Pentagon centre now is, near the Brook Theatre but it is not there yet. Very strange to see.