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Hi, i  asked you before if it is possible for humans to emit higher levels of ionizing radiation than the background radiation and you said yes. And i just found on another website that says we don't , so which answer is correct?

40K emits gamma rays in a little over 10 percent of its decays and most of these gamma rays escape the body. A gamma ray is emitted in about one out of every 10 disintegrations of 40K, implying that about 500 gamma rays are produced each second. These will be moving in all directions, some will be attenuated in the body, and the dose rate from these gamma rays outside of the individual's body will represent a very small fraction of the normal background dose rate from all natural sources outside the body.

If a person is above average in weight, the dose rate outside of this person's body will expectedly be higher than the dose outside the body of a lower-weight individual. In both cases, however, the dose rate will be extremely small compared to the normal background dose rate.

I don't understand your confusion.  My calculations agree quite well with your other article.  You do emit radiation into the surrounding environment.  You don't emit more than other things do, just an amount that technically could be measured (they mention a whole-body counter doing this specifically) in addition to whatever you're around.  I also said that you never specified your outside background radiation, so there's no comparison to be made.  If you wanted a comparison like that, then their value estimate of 10% of the external and inhaled exposure for your own dose is pretty good...depending very heavily on where you live and what that background radiation is.  There's no disagreement between my answer and the one from


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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