The largest fraction of the natural radiation exposure we receive comes from a radioactive gas, radon and its decay products (nearly 50%). The radon gas can enter to the body via respiring, drinking and eating and caused damage to respiratory and digestion systems. Also radium-226 is widely distributed in the environment. When a person ingests radium, this element deposits in bones and cause to...

background; environmental gamma ray refers to the gamma radiation from terrestrial sources and building materials. in enclosed spaces radiation can become a health hazard leading to potential increase in the rates of lung cancer. the goal of this study is to assess the exposure to natural gamma radiation of children in the schools of zanjan province. method; the natural gamma radiation was asse...

Applied to skin color, the sexual selection hypothesis proposes that male preference for light-skinned females explains the presence of light skin in areas of low solar radiation. According to this proposal, in areas of high solar radiation, natural selection for dark skin overrides the universal preference of males for light females. But in areas in which natural selection ceases to act, sexua...

Temperature measurements are important for thermal-structural experiments in the thermal radiation heating environments such as used for thermal-structural stress analyses. This paper describes the use of multicolor pyrometry for the measurements of diffuse surfaces in thermal radiation environments that eliminates the effects of background radiation reflections and unknown emissivities based o...

Background: All human beings and living organisms are exposed to natural radiations on daily basis, which is mainly due to the activity concentration of primordial radionuclides 232Th, 238U and their products of decay together with the natural radionuclide 40K present in the earth’s crust. Materials and Methods: A total of 59 soil samples were collected around the banks and surroundings of the ...

 ABSTRACTBackground: There are relatively rich uranium mines in regions of Saghand and Bafgh in Yazd province. This survey was carried out to provide a map of ambient gamma radiation of Yazd province and the probable effects of the existence of these mines on background radiation dose rates.Materials and Methods: The measurements of the outdoor and indoor–environmental exposures (including cosm...

There is a vigorous debate about whether or not there may be a "threshold" for radiation-induced adverse health effects. A linear-no threshold (LNT) model allows radiation protection practitioners to manage putative risk consistently, because different types of exposure, exposures at different times, and exposures to different organs may be summed. If we are to argue to regulators and the publi...