Natural radiations

During heat dissipation by radiation the colour and condition of the surface plays a similar role. Dark-coloured bodies dissipate more heat than the light-coloured ones. The amount of heat absorption and emission for the same body may therefore be assumed to be almost the same. Accordingly, Table 31.1, for selected colours, may be considered for the coefficients of absorption and emission of heat due to solar radiation and natural radiation respectively. 

Table 31.1 Coefficients ol absorption (ol solar radiation) and emission (natural radiation) for a metallic surface located outdoors...

We have considered the emission of heat, from the surface through natural radiation, nearly the same, as its absorption of heat through solar radiation. 

When it comes to radioactivity, there is scientific controversy about the effect of low levels of radiation i.e. levels well below those of natural radiation. Some believe the effect to be zero or even positive, whilst others suggest that any increase in radioactivity, however small, increases the chance of cancer. 

Bosnjakovic, B., P.H. van Dijkum, M.C. O Riordan, and J. Sinnaeve, eds., Proceedings of Exposure to Enhanced Natural Radiation and Its Regulatory Implications, Sci. Total Environ., Volume 45 (1985)... 

Powers, R.P., Turnage, N.E., and Kanipe, L.G., Determination of Radium-226 in Environmental Samples, in Proc. Natural Radiation Environment III,... 

Tanner, A.B., Radon Migration in the Ground a Supplementary Review, in Proc. Natural Radiation Environment III. Conf-780422, (Gesell, T.F., and Lowder, W.M., eds.) pp. 5-56, U.S. Dept, of Commerce, National Technical Information Service, Springfield VA, (1980). 

George, A. C. and Breslin, A. J. The Distribution of Ambient Radon and Radon Daughters in Residential Buildings in the New Jersey - New York Area. Natural Radiation Environmental III, Vol. 2, C0NF-780422, Technical Information Center, U. S. Department of Energy, Springfield, VA (1980). 

Jacobi, W. and Paretzke H.G. 1985, Risk Assessment for Indoor Exposure to Radon Daughters, In Proceedings, Seminar on Exposure to Enhanced Natural RAdiation and Its Regulatory Implications, Maastricht, the Netherlands, March 25-27, Elsvier Science Publisher, Amsterdam. 

Castren, 0., The contribution of bored wells to respiratory radon daughter exposure in Finland. Proc. of Symposium on Natural Radiation Environment, (C0NF- 780422, vol.2.) pp. 1364-1370, Houston, Texas (1978). 

McAulay, I.R. and McLaughlin, J.P., Indoor Natural Radiation Levels in Ireland. Sci. Total. Environ. 45 319-325 (1985). 

Sinnaeve, J., Olast, M. and McLaughlin, J., Natural Radiation Exposure Research in the Member States of the European Community State of the Art and Perspectives. Presented at APCA Speciality Conference on Indoor Radon Philadelphia, U.S.A. (Feb. 1986). 

Kawano, M. and S. Nakatani, Some properties of Natural Radioactivity in the Atnmosphere, in The natural Radiation Evviroment, (J. A. S. Adams and W. M. Lowder, ed) pp. 291-312, Univ. Chicago Press,... 

Porstendorfer, J., A. Wicke, and A. Schraub, Method for a Continuous Registration of Radon, Thoron, and Their Decay Products Indoors and Outdoors, in The Natural Radiation Environment III, (T. F. Gesell and W. M. Lowder, ed) pp. 1293-1307, Technical Information Center/U.S. DOE, Springfield (1980). 

Wicke, A. and Porstendorfer, J., Radon daughter equilibrium in dwellings, in Natural Radiation Environment (K.G.Vohra, ed.), Wiley Eastern Limited, 481-488 (1982)... 

Reineking, A., Becker K.H. and Porstendorfer, J., Measurement of the Unattached Fractions of Radon Daughters in Houses, Presented to the Seminar on Exposure to Enhanced Natural Radiation and its Regulatory Implications, Maastricht, The Netherlands (1985). 

Steinhausler, F., W. Hofmann, E. Pohl, and J. Pohl-Ruling, Local and Temporal Distribution Pattern of Radon and Daughters in an Urban Environment and Determination of Organ Dose Frequency Distributions With Demoscopical Methods, in Proceedings of the Symposium on Natural Radiation Environment. III. Houston. Conf-780422, DOE Sym. Ser. 51, Vol. II, pp. 1145-1161, Houston NM,... 

Chameaud, J., Masse, R. and Lafuma, J., Influence of Radon Daughter Exposure at low Doses on Occurrence of Lung Cancer in Rats, in Radiation Protection Dosimetry Indoor Exposure to Natural Radiation and Associated Risk Assessment, (Clemente, G., F. et al, eds) pp.385-388, Nuclear Technology Publishing, Anacapri (1983). 

We have previously documented the methodology (Marks et al., 1985a) and presented a summary of the technique (Marks et al., 1985b) at the Maastricht, The Netherlands, Seminar on Exposure to Enhanced Natural Radiation and Its Regulatory Implications. This paper represents a synthesis of the work we have conducted to date on risk assessment at uranium mill tailings vicinity properties. 

Jonassen, N., and J.P. McLaughlin, Exhalation of Radon-222 from Building Materials and Walls, in Natural Radiation Environment III (T.F. Gesell and W.M. Lowder, eds.) pp 1211-1224, National Technical Information Center, U.S. Department of Commerce, Springfield, Va. (1980). 

There is an increasing concern regarding the exposure of the general population to increased levels of radon decay products in indoor air. The exposure to the public from increased levels of natural radiation has been the subject of a conference held in Maastricht, The Netherlands, in March 1985 where a number of reports were presented showing high levels of radon in the indoor environment. Other reports in this volume also demonstrate that high levels of radon are not as uncommon as had been previously thought. 

Guimond, R.J., Regulation and Guidelines for Enhanced Natural Radiation in the United States, Science of the Total Environment 45 641-646 (1985). 

Exposure to natural sources of radiation is unavoidable. Externally, individuals receive cosmic rays, terrestrial X-rays, and gamma radiation. Internally, naturally occurring radionuclides of Pb, Po, Bi, Ra, Rn, K, C, H, U, and Th contribute to the natural radiation dose from inhalation and ingestion. Potassium-40 is the most abundant radionuclide in foods and in all tissues. The mean effective human dose equivalent from natural radiations is 2.4 milliSieverts (mSv). This value includes the lung dose from radon daughter products and is about 20% higher than a 1982 estimate that did not take lung dose into account (Table 32.4). 

Figure 32.4 Natural radiations in selected radiological domains. (Modified from Folsom, T.R. and J.H. Harley. 

Folsom, T.R. and J.H. Harley. 1957. Comparisons of some natural radiations received by selected organisms. Pages 28-33 in National Academy of Sciences. The Effects of Atomic Radiation on Oceanography and Fisheries. Publ. No. 551, Natl. Acad. Sci.-Natl. Res. Coun., Washington, D.C. 

The human body is equipped to deal with nominal levels of radiation doses. Background (natural) radiation from radon gas, cosmic sources, soil, and water produces an average dose of about 0.3 rem (0.003 Sv) per year.4 However, large doses of radiation generated after a terrorist attack can overwhelm the body s ability to repair damage, leading to stochastic or acute health effects. 

The study was performed in patients exposed to ionizing radiation after Chernobyl accident. Comparison groups included patients and healthy individuals exposed to the natural radiation levels. Control group included healthy volunteers who resided in Kyiv since Chernobyl accident Distribution by diagnosis is presented at table 1. Investigated persons were at the age of 43-72 (mean+SD for the exposed group 52,3 + 10,1 yrs for control group- 46,3 + 11,3 yrs). All studied persons participated by informed consent. Peripheral blood and bone marrow samples were obtained by a standard procedure (National. Committee for Clinical Laboratory Standards, 1991). Flow... 

Comparison groups exposed at natural radiation levels ... 

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