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EPA Makes a Rad Decision
New submitter QuantumPion writes
"The Environmental Protection Agency released draft guidelines last month that could significantly relax radiation hazard standards in the case of a radiological event in the United States by using risk-based decisions. The goal is to have limits that make sense in an emergency that are different from the limits in day-to-day life. From the article: 'Currently, the only guidance are the extremely strict standards that apply for EPA Superfund sites and nuclear plant decommissioning, which are as low as 0.010–0.025 rem/year, far below the natural background levels in the U.S. of 0.300 rem/year, and even well below the average amount of radioactive materials that Americans eat each year. And these guidelines aren’t really different from the 1992 PAG, except in the area of long-term cleanup standards and, perhaps, standards for resettlement. What’s the big deal here? As radworkers, we’re allowed to get 5 rem/year. 2 rem/year doesn’t rate a second thought. ... No one has ever been harmed by 5 rem/year, so setting emergency levels at 2 rem/year is pretty mild and more than reasonable. ... Think of it this way. The situations covered by these new guidelines are similar to someone dying of thirst who has the chance to drink fresh water having 2,000 pCi per gallon of radium in it. While the safe drinking water levels are 20 pCi/gal for Ra, 2,000 pCi/gal is of no threat, especially if you’re going to die from imminent dehydration. Of course, a bag of potato chips has 3,500 picocuries, so go figure.'"
Of course, potatoes can't be produced from material free of radioisotopes..... http://www.livestrong.com/article/303878-a-list-of-the-most-radioactive-foods/
Potatoes contain gobs of potassium, which has a naturally occurring radioactive isotope (K40). Bananas have the same issue. Unlike C14, K40 is primordial, so everywhere you have potassium, you have essentially the same concentration of K40.
The only radioactive isotope of carbon is C14. The amount of C14 versus C12 is roughly 0.0000000001%. That is one part in one trillion. A human body has roughly 80 trillion cells.
Yes.
So 80 of your cells contain *ONE* atom of C14. Your whole body contains 80 C14 atoms ...
No. An 80-kilogram person has about 14 or 15 kg of carbon atoms. This works out to trillions of carbon atoms per human cell. Therefore every cell has approximately one atom of C14, and the human body as a whole has almost a quadrillion C14 atoms.
Incorrect. Sieverts are specifically designed to account for the differences between radiation types with regards to biological effects. 1 Sv has the same biological impact regardless of whether it was caused by alpha, beta or gamma radiation. If the radiation is given in Grays, then you need to apply correction factors depending on radiation type.