University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Doctoral Thesis:
Michael Stietka
(2017):
Strahlenexposition von Personen durch natürliche Radionuklide in Zusammenhang mit Trinkwasserproduktion.
Doctoral Thesis - Institut für Bodenforschung (IBF),
BOKU-Universität für Bodenkultur,
pp 155.
UB BOKU
obvsg
- Abstract:
- Through ground or spring water, Rn-222 enters waterworks, where it can exhale into the indoor air through open water surfaces, and may increase health risks of the workers. Based on investigations in 21 Austrian waterworks, this work proves a significant, occupational radiation exposure for employees of waterworks caused by Rn-222 progenies. Within the scope of this work, various influence parameters on the Rn-222 activity concentrations in indoor air of waterworks were evaluated. Among the investigated influence parameters are the Rn-222 activity concentrations in water as well as meteorological, hydrogeological and indoor climate parameters. The also investigated influence of the ventilation, which is considered as the most important factor, strongly overlays other effects. The ventilation is also one cause of the observed seasonal variations of the Rn-222 activity concentrations in indoor air. Hazard sources arising from natural radioactivity in waterworks are primarily due to the potentially increased exposures resulting from Rn-222, but also other natural radionuclides such as Ra-226 can be enriched in residues and working materials. This was proven by gamma spectrometric analyses of residue samples. Specific problems due to interfering gamma lines, which may occur during the gamma-ray spectrometry of NORM, were analyzed and suitable correction factors were compiled from literature. The Rn-222 loss caused by the leakage of the sample containers is a common problem with gamma spectrometric analyses of NORM. Based on active Rn-222 detectors, a simplified method to quantify the Rn-222 loss was developed and presented within this work.
- Betreuer: Maringer Franz Josef
- 1. Berater: Gerzabek Martin