I gave packages of potassium iodide to all of my friends and family as stocking stuffers for Christmas a few years back, they all think I am a little crazy, but, oh well...
Bookmark to mapper.
The shock wave overpressure on tactical nukes is actually around 6 psi (yep, the Hiroshima and Nagasaki bombs were the size of today's tactical nukes). If I remember correctly, a dose of 2000 R results in the breakdown of the central nervous system in about 2 days. 500 to 600 R results in the death of 50% of those exposed by the destruction of the GI tract lining in about 2 weeks along with suppressing the immune system (think of terminal stage AIDS). 50-60 R makes you sick to your stomach and increases your chance of cancer. And this discussion points out why we should treat anyone who decides to pursue a nuclear or (even worse) biological weapon program as a potential enemy of humanity until proven otherwise.
Next time, don't tell them your Freeper handle.