Contribution of natural terrestrial sources to the total radiation dose to man

Thesis. Submitted by J. A. Auxier to Georg:a Inst. of Tech., Atlanta. The central objective of this research was the analysis and synthesis of data available concerning human exposures to the natural terrestrial radiation environment and the solution of some key- prob1ems that appeared to be hampering the understanding of it. A better knowledge of the natural radiation environment appears to be necessary to a realistic interpretation of the effects of low levels (for example, current occupationa1 guide levels) of radiation exposure of man. Specific objectives included a determination of the important parameters affecting radon emanation from concrete, the measurement and correlation of the gamma ray' spectra from radionuclides for typical concentrations in soil, a determination of the possibility and practicability of using high resolution spectrometers to measure low levels of radioactive contamination due to human activities, and an evaluation of major sources of external and internal human exposure due to the natural radiation environment. (CH)