You're forgetting internal uptake... when you inhale or swallow hot particles. If the uptake is significant enough, refer to the comment ragarding stepping in front of a train (man, that's a good line <img src="/images/graemlins/wink.gif" alt="" />), if the uptake isn't that significant, anything in your lungs just has to "burn" itself out... radioactive half-life of the particle will determine how long you remain "hot". If the particle is swallowed, it's common practice in the trades to drink plenty of beer, and hopefully, you'll "flush" the problematic particle out of your system.
Again, it's not real technical, but that's what the folks that are dealing with it on a daily basis are doing <img src="/images/graemlins/wink.gif" alt="" />

Troy