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H Tsertos

Publications and source records attributed to H Tsertos.

7 recordsLinked to original sources
PubMed2006

Indoor and outdoor in situ high-resolution gamma radiation measurements in urban areas of Cyprus.

In situ, high-resolution, gamma-ray spectrometry of a total number of 70 outdoor and 20 indoor representative measurements were performed in preselected, common locations of the main urban areas of Cyprus. Specific activities and gamma absorbed dose rates in air due to the naturally occurring radionuclides of (232)Th and (238)U series, and (40)K are determined and discussed. Effective dose rate to the Cyprus population due to terrestrial gamma radiation is derived directly from this work. The results obtained outdoors match very well with those derived previously by high-resolution gamma spectrometry of soil samples, which were collected from the main island bedrock surface. This implies that the construction and building materials in urban areas do not affect the external gamma dose rate; thus they are mostly of local origin. Finally, the indoor/outdoor gamma dose ratio was found to be 1.4 +/- 0.5.

Air Pollutants, Radioactive↗
PubMed2004

A comprehensive study of natural gamma radioactivity levels and associated dose rates from surface soils in cyprus.

A survey was carried out to determine activity concentration levels and associated dose rates from the naturally occurring radionuclides 232Th, 238U and 40K, in the various geological formations of Cyprus, by means of high-resolution gamma ray spectrometry. A total of 115 representative soil samples were collected from all over the bedrock surface of the island, based on the different lithological units of the study area, sieved through a fine mesh, sealed in 1000 ml plastic Marinelli beakers and measured in the laboratory with respect to gamma radioactivity for a counting time of 18-h each. From the measured spectra, activity concentrations were determined for 232Th (range from 1.0 x 10(-2) to 39.8 Bq kg(-1)), 238U (from 1.0 x 10(-2) to 39.3 Bq kg(-1)) and (40)K (from 4.0 x 10(-2) to 565.8 Bq kg(-1)). Gamma absorbed dose rates in air outdoors were calculated to be in the range from 1.1 x 10(-2) to 51.3 nGy h(-1), depending on the geological features, with an overall mean value of 8.7 nGy h(-1) and a standard deviation of 8.4 nGy h(-1). This value is by a factor of about seven below the corresponding population-weighted world-averaged value of 60 nGy h(-1) and one of the lowest that has been reported from similar investigations worldwide. Assuming a 20% occupancy factor, the corresponding effective dose rates outdoors equivalent to the population were calculated to be between 1.3 x 10(-2) and 62.9 microSv y(-1), with an arithmetic mean value of 10.7 microSv y(-1) and a standard deviation of 10.3 microSv y(-1).

Background Radiation↗
PubMed2003

Indoor radon (222Rn) concentration measurements in Cyprus using high-sensitivity portable detectors.

Using high-sensitivity radon ((222)Rn) portable detectors (passive electronic devices of the type RADIM3), the airborne (222)Rn concentration in the interior of various Cypriot buildings and dwellings was measured. For each preselected building and dwelling, a calibrated detector was put into a closed room, and the (222)Rn concentration was registered in sampling intervals of 2 to 4 h for a total counting time of typically 48 h. (222)Rn activity concentrations were found to be in the range of 6.2 to 102.8 Bq m(-3), with an overall arithmetic mean value of (19.3+/-14.7) Bq m(-3). This value is by a factor of two below the world average (population-weighted) value of 39 Bq m(-3). The total annual effective dose equivalent to the Cypriot population was calculated to be between 0.16 and 2.6 mSv with an overall arithmetic mean value of (0.49+/-0.37) mSv.

Air Pollutants, Radioactive↗