Dongen R vanZanten R van2012-12-122012-12-121992-02-29http://hdl.handle.net/10029/259032Abstract niet beschikbaarThis report contains the results of dose rate measurements carried out during 1990 at the site of the National Institute of Public Health and Environmental Protection. The dose rates were determined by means of thermoluminescence dosimeters on twelve locations. One of these locations was meant for determination of the natural background (reference) on the site. The dose rates averaged over a year, appeared not to deviate significantly from the natural background levels in the Netherlands. The small increase of the annual mean of the dose rate near the building Sg, with regard to the reference level is due to irradiation activities for calibration work and the replacement of the old Co-60-source by a new one in July 1990 with a higher activity.16 pnl1692-1natuurlijke achtergrondstraling; thermoluminescentiedosimetersdosistempiReport2012-12-12