I was researching the Kyshtym (nuclear) Disaster, and it said that it released 20 MCi (20 megacuries) of radiation into the air in a dust cloud.
I read from this Yahoo Answers answer that:
The curie is the old unit of activity and a very big unit it was.
1 curie = 3.70 x 10^10 disintegrations per sec.
In today's units 1 curie is about 30 Giga Becquerel.
So a curie of any radioactivity (alpha, beta or gamma) would fry you.
A sealed microcurie source could be safely handled.
If a single curie is this powerful, then what would twenty million curies (a 20 MCi) be like? Could you give any examples of events that exemplify this scale of radiation and damage (if you can't think of any real ones, then maybe a theoretical example)?