Back in the 1950's when we conducted above ground nuclear tests, the Air Force had these 5 men and 1 photographer stand out in the open to witness a 2K blast from an air launched nuclear missle. The blast happened at 18,500 feet above their heads. The Air Force wanted the public to know, that the radiation from something like this wouldn't be that much of a problem.
Watch this video of these guys during the test, especially when the shock wave hits them. The dialog is something to listen too also, after the blast, one guy wishes more people could be there to see this!
http://now.msn.com/men-stand-under-a...propagada-film