In some areas, Radon is not completely avoidable. Mostly it seeps into basements. Radon ventilation systems are very effective, they can reduce this amount at least 50% and maybe 80%, just depends how much air you want to move. So instead of a 37% of your exposure if you reduce that 80% it is 7.5%, plus 5% cosmic, and 3% soil, that is 15%. So by "so called 'natural sources" like med procedures, nuke medicine, those items are jacking up your dose like 400% to 700% from where is could be "naturally". the whole natural radiation lie, unravels as a complete joke... about half of us will contract cancer in our lives, and yet you can't prove that any one source caused it. Therefore by the "Scientific Method" radiation cannot be proven to be unsafe, therefore the PNPs Pro Nuke Pimps will state that "natural radiation" is proven to be safe, and therefore a little extra disaster radiation is OK too. Check the chart closely, the PNP lies immediately emerge.
