Potassium background radiation from

Thinking Critically Is the data for the background radiation and the radiation from the potassium-containing sample consistent or random in nature Propose an explanation for the pattern or lack of pattern seen in the data. 

It is at present somewhat uncertain if very low levels of radiatirm are harmful. We cannot avoid all radiation since there is a natural radiation background (with approximate yearly exposure) due to, for example, the cosmic rays (40 millirem at sea level, 250 Rem at 500 m elevation) radium and radon in ground and building material (40 Rem) and potassium 40 (18 Rem). In addition, we can add some man-made radiation sources such as one chest X-ray (40 Rem), one dental X-ray (20 Rem), fallout from nuclear explosions (5 Rem), as well as miscellaneous sources such as TV, CRT, etc., all of which total to 163 Rem/year (for sea level). The average annual radiadmi dose to a nuclear reactor worker in Ontario is 0.68 Rem with an annual limit of 5 Rem set by radiation protection regulations. 

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