Radon: emanation

Morawska L, Philhps CR (1992) Dependence of the radon emanation coefficient on radium distribution and internal stractnre of the mineral. Geochim Cosmochim Acta 57 1783-1797 Neretnieks I (1980) Diffusion in the rock matrix an important factor in radionuclide retardation J Geophys Res 88 4379-4397... 

Sisigina, T.I., Assessment of Radon Emanation from the Surface of Extensive Territories, in Nuclear Meteorology pp. 239-244, Israeli Program of Scientific Translations, Jerusalem, (1974). 

Strong, K.P., and Levins, D.M., Effect of Moisture Content on Radon Emanation from Uranium Ore and Tailings, Health Phys. 42 27-32 (1982). 

Thamer, B.J., Nielson, K.K., and Felthauser, K., The Effects of Moisture on Radon Emanation Including the Effects on Diffusion, Report BuMines 0FR 184-82, PB83-136358, U.S. Dept, of Commerce,... 

Charcoal-Trap Method (ACC). The Charcoal-Trap Method has been used for sampling radon gas in the atmospheric air and for measuring radon emanation rate from the soil surface by some researchers (e. g. 

Fleischer, R. L. and A. Mogro-Campero, Mapping of Integrated Radon Emanation for Detection of Long-Distance Migration of Gases Within the Earth Techniques and Principles,. 1. Geophvs. Res. 83(B7) 3539-3549 (1977). 

The concentration of radon decay products and therefore the factors F and fp are influenced by the basic processes of the attachment, recoil and deposition (plateout) and by room specific parameters of radon emanation and ventilation (Fig. 1). ... 

The radon emanation and the ventilation rate of a room can be derived from the increase of the radon concentration by the radon exhalation and from the steady state condition between exhalation and air exchange with the free atmosphere. In Fig. 2 the variation of the radon concentration as function of time is shown measured in two houses with different radon emanations and ventilation rates. 

All our measurements i/ere carried out in rooms with i < 1 hr1 and the radon concentration outdoors (c 5 Bq nr 3) i/as always much smaller than indoors (cj > 100 Bq m 3). Assuming a constant radon emanation, a homogeneous activity distribution and 100 % prefiltering of the free fractions of the incoming air, the radon, the free and attached radon daughter activity concentrations indoors (cj cjf cja) and outdoors (eg c f c a) under steady conditions are ... 

The 210Pb input from the atmosphere must have been constant over the past 150 years due to the relative constancy in the maritime climate (temperature and soil moisture influences the radon emanation rate) and the resulting constancy in the input source for 210Pb. Therefore, the deviations from a single log-linear relationship of the unsupported 210Pb activity with the dry mass of sediment accumulation must be due to some property of the watershed. The three different relationships shown in... 

ACTINON. The name of the isotope of radon (emanation), which occurs in the naturally occurring actinium, series being, produced by alpha-decay of actinium X, which is itself a radium isotope. Achnon has an atomic number of 86, a mass number of 219, and a half-life of 3.92 seconds, emitting an alpha particle to form polonium-215 (Actinium A). See also Chemical Elements and Radioactivity. 

A radioactive element is an element that disintegrates spontaneously with the emission of various rays and particles. Most commonly, the term denotes radioactive elements such as radium, radon (emanation), thorium, promethium, uranium, which occupy a definite place in the periodic table because of their atomic number. The term radioactive element is also applied to the various other nuclear species, (which arc produced by the disintegration of radium, uranium, etc.) including (he members of the uranium, actinium, thorium, and neptunium families of radioactive elements, which differ markedly in their stability, and are isotopes of elements from thallium (atomic number 81) to uranium (atomic number... 

Davis NM, Hon R, Dillon P. 1987. Determination of bulk radon emanation rates by high resolution gamma ray spectroscopy. In Graves B, ed. Radon, radium, and other radioactivity in ground water. Chelsea, Ml, Lewis Publishers, 111-122. 

Ingersoll, J.G. (1983) A survey of radionuclide contents and radon emanation rates in building materials used in the U.S. Health Physics, 45, 363-8. 

Average radon emanation coefficients in different media for nine different ores... 

National Technical Information Service, US Dept, of Commerce, Springfield, Va., 959 pp. Adkinson, C.W. and Reimer, G.M., 1976. Helium and radon emanation bibliography - selected references of geologic interest to uranium exploration. US Gcol. Survey, Open File Report, 76-... 

Austin, S.R., 1975. A laboratory study of radon emanation from domestic uranium ores. Radon in uranium mining, IAEA Vienna, PL-565/8, pp. 151-160. 

Cheng, K.C. and Porritt, J.W.M., 1981. The measurement of radon emanation rates in a Canadian cut-and-fill uranium mine. Can. Inst. Min. Metall. Bull., 74 110-118. 

Fleischer, R.L. and Mogro-Campero, A., 1978. Mapping of integrated radon emanation for deteetion of long-distance migration of gases within the Earth techniques and prineiples. J. Geophys. Res., 83 3539-3549. 

Fleischer, R.L., Hart, H.R. and Mogro-Campero, A., 1980. Radon emanation over an ore body search for long-distance transport of radon. Nuclear Instmments and Methods, 173 169-181. 

King, C.Y., 1978. Radon emanation on San Andreas fault. Nature, 271 516-519. 

Semkow, T. M., and P. P. Parekh. 1990. The role of radium distribution and porosity in radon emanation from solids. Geophys. Res. Letters l7(6) 837-40. 

Thamer, B. j., K. K. Nielson, and K. Felthauser. 1981. The effects of moisture on radon emanation. U.S. Bureau of Mines Open-file Rept. 184-82. 

Chemical analyses were performed in accordance with ASTM Chemical Analysis of Gypsum and Gypsum Products (C 471). Fluoride and phosphorus were determined by the Association of Florida Phosphate Chemists Methods (7). Uranium was determined by ASTM Tests for Microquantities of Uranium in Water by Fluorometry (D 2907), and thorium was determined by ASTM Test Method for Thorium in Water and Waste Water (D 2333). Radium was determined by the radon emanation method (51, and uranium and thorium isotopes were determined by a chromatographic and radiological technique developed by the EPA. 

Douglas. G. S., Ed.. "Radium by Radon Emanation Method." Radioassay Procedures for Environmental Samples, U.S. Public Health Service Publication No. 999-RH27. Rockville. MD. 1967. pp. (4-36H4-45I. 

In this equation D (m2.s 1) represents the radon diffusivity, X the radioactive decay constant (s 1), C (Bq.m3) the radon concentration in the pore space, R (Bq.kg1) the radium concentration in the material, p (kg.m3) the bulk density of the dry material, E (dimensionless) the radon emanation power coefficient for the pore spaces, s (dimensionless) the total porosity and 0 (dimensionless) the moisture. The solution of the diffusion equation for an homogeneous medium represents the flux release from the waste material to the surface, Jt (Bq.m 2.s ). For a system without cover we obtain (Rogers, 1984) ... 

Ra activity in the bottom water radon emanation rate in sediment °Th activity in the particles activity of... 

The accuracy of any measurement will depend upon the calibration of the instrument used. The calibration of an instrument determines its response to a known amount or concentration of radioactivity. This allows a correlation to be made between the instrument reading and the actual amount or concentration present. A range of activities of radium-226 standard reference materials (SRM) is available from the U.S. Department of Commerce, National Bureau of Standards (NBS) as solutions for calibrating detection systems. Also, an elevated radon atmosphere may be produced in a chamber, and samples drawn and measured in systems previously calibrated by radon emanation from an NBS radium-226 SRM. Other radon detectors may then be filled from or exposed in the chamber and standardized based on this "secondary" standard (NCRP 1988). Analytical methods for measuring radon in environmental samples are given in Table 6-2. These methods provide indirect measurements of radon i.e., the activity emitted from radon and radon progeny is detected and quantitied. 

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