Gamma background measurements in the Laboratoire Souterrain de Modane

In situ gamma-ray measurements were taken at six locations in the Modane Underground Laboratory. Count rates for gamma radiation within the energy range of 7–2734 keV varied from 15 to 108 cs-1. The arithmetic mean was 79 cs-1 for measurements taken without a collimator. The metamorphic rocks surrounding the Lab are characterized by low activity concentrations of uranium and thorium equal to 12 and 10 Bq kg-1, respectively

Gamma background measurements in the Gran Sasso National Laboratory

In situ gamma-ray measurements were taken at eight locations in the Gran Sasso National Laboratory (Italy). Count rates for gamma radiation within the energy range of 7–2,734 keV varied from 8 to 60 c s-1. The arithmetic mean was 49 c s-1 for measurements taken without a collimator. The average gamma flux inside the Lab was 0.25 c cm-2 s-1. The sedimentary rocks surrounding the Lab are characterized by low activity concentrations of uranium and thorium, equal to 1.7 and 1.4 Bq kg-1, respectively

The occurrence of 226Ra and 228Ra in groundwaters of the Polish Sudety Mountains

The paper presents preliminary measurement results of the concentrations of 226Ra and 228Ra isotopes in the groundwaters of the Polish part of the Sudety Mountains. The analysis of sampling results for water from 55 intakes showed that the average concentrations amount to 0.144 Bq/dm3 for 226Ra and 0.083 Bq/dm3 for 228Ra, while the extreme values reach 0.007 and 0.92 Bq/dm3 for 226Ra, and 0.004 and 0.4 Bq/dm3 for 228Ra. The activity ratio 228Ra/226Ra in the examined groundwaters ranges between 0.099 and 2.059. The result of the conducted research implies that the highest concentrations of 226Ra and 228Ra occur in the waters with the highest general mineralization (the highest values of total dissolved solids (TDS))

Long lived natural radioactive elements in SPA waters of southern Poland - dose assessment and health hazard evaluation

The aim of this study was to determine the activity concentrations of 234;238U isotopes in mineral, medicinal and spring waters in spas situated in the Sudety and the Outer Carpathian Mountains and to compare the uranium content found in waters from these regions. Samples were collected over a period of 7 years (2005–2011) from 86 water intakes from the Sudety Mountains and Fore-Sudetic block and from 37 water intakes from Outer Carpathians. On the basis of the calculated activity concentrations of 234;238U as well as the existing data on 226;228Ra, the annual effective doses resulting from the consumption of these isotopes were evaluated

Test measurements of thoron concentration using two ionization chambers AlphaGUARD vs. radon monitor RAD7

The experiment aiming at testing the possibility of using AlphaGUARD monitors based on an ionization chamber for thoron measurements is presented. A single AlphaGUARD monitor working in the flow mode was applied to measure thoron concentration in the radon-free atmosphere. The sensitivity (correction factors) of the monitor to thoron was estimated by comparison with a RAD7 portable detector (Durridge Company), based on spectrometric analysis, in the thoron, radon-free atmosphere in a calibration chamber. This depends on the applied flow rate and changes from 8% for the flow rate of 0.3 dm3/min to 36% for 1 dm3/min. It was also revealed that the sensitivity of the monitor to thoron in the diffusion mode is equal to ca. 5% and may be neglected. The method involving two Alpha-GUARD monitors working in two different modes (diffusion and flow) at the same time may be used to evaluate radon and thoron concentration in the natural environmental conditions where usually both isotopes appear together. In this method thoron concentration is estimated as the difference of results obtained from two AlphaGUARD monitors multiplied by the correction factor corresponding to the applied flow rate. The devices based on spectrometric analysis, e.g. RAD7 seem to be a better tool for thoron measurements in the environmental conditions

Natural radioactivity of groundwater from the Przerzeczyn-Zdrój Spa

The present authors performed investigations of natural radioactivity in groundwater from the Przerzeczyn- -Zdrój Spa. Some of the waters are regarded as medical and are used for balneological purposes. Samples from seven groundwater intakes were collected 5 times over a period of 8 years (1999–2007). In order to obtain necessary data, two different nuclear spectrometry techniques were applied: α spectrometry and liquid scintillation spectrometry. The activity concentrations of 222Rn varied in the range from 15±2 Bq/l to 154±22 Bq/l. The results of activity concentrations of 226,228Ra varied from below 10 mBq/l to 30±1.5 mBq/l and from below 30 mBq/l to 60±4 mBq/l, respectively. Activity concentration lower than minimum detectable activity (MDA) was obtained for 3 samples for 226Ra and 4 for 228Ra determinations out of 7 investigated samples. The uranium content in the studied samples was determined once and the value ranged from 4.5±0.6 mBq/l to 13.6±1.2 mBq/l for 238U and from 17.1±0.9 mBq/l to 52.2±2.8 mBq/l for 234U. All obtained values for uranium isotopes showed activity concentrations above MDA. The activity ratios 234U/238U, 222Rn/226Ra and 226Ra/238U and the correlations between different isotopes concentrations were evaluated

Annual observations of radon activity concentrations in dwellings of Silesian Voivodeship

In the paper, results of year-long measurements of radon levels in dwellings on the premises of Silesian Voivodeship are presented. Track etched detectors with polymer CR-39 foils were used in the investigations. As the studied buildings were located in different regions of Silesian Voivodeship, therefore results of measurements were analysed due to possible influence of geological structure or effect of mining operations in places, where given dwellings were situated. Elevated concentrations of radon were measured mostly in dwellings located in areas, where permeable Triassic limestone and dolomite occur, as it has been predicted. On the other hand, the impact of mining activity such as disintegration of rock-body and activation of faults plays an important role, too, because it enables radon migration and its entry into buildings. Beside the analysis of seasonal variations of radon activity concentration, the impact of temperature and pressure on these fluctuations outdoor and indoor buildings has been analysed

Measurements of natural radioactivity in the salt cavern of the Polkowice-Sieroszowice copper mine

Due to their low radioactivity background, underground physics laboratories offer a unique possibility for investigating extremely rare phenomena like proton decay, dark matter signals or neutrino physics/astrophysics related issues. The knowledge of the natural radioactivity background is essential for the success of an underground physics experiment. The following measurements of the natural radioactivity background, in the foreseen location of an underground physics laboratory in the salt layer, in the Polkowice–Sieroszowice copper mine are presented: concentration of natural radio-isotopes from in situ obtained gamma-ray spectra and from alpha spectroscopy of rock samples, radon concentration in the air and the dose determination