Henry Spencer wrote:
Orion's fallout output..."urk!"

"The lifetime risk of a death due to cancer is about 20% absent the
fallout radiation exposure. The (438 megatons of airborne) fallout
putatively raises that risk to about 20.03%..."
http://newton.nap.edu/books/030909156X/html/373.html

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"100 megatons' worth of nuclear weapons in the atmosphere each year.
A full-fledged Orion mission would have increased the amount of fallout
from those tests by 1 percent."
http://www.discover.com/issues/feb-0...t-rocket-ever/

Q.E.D.
20.0300685
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Do you worry enough about the 20%? Will you let the 0.0000685% cripple
our destiny?

Have you heard of the quadratic does response model?... hormesis?