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FACTORS AFFECTING THE RADIATION DOSE TO INHABITANTS IN A SMALL NEW HOUSING ESTATE IN THE NETHERLANDS

P. de Jong and W. van Dijk
TNO Centre for Radiological Protection and Dosimetry
PO Box 9034, 6800 ES Arnhem, The Netherlands
Phone: (+31-26) 3563055. Fax: (+31-26) 4450787. E-mail: p.dejong@csd.tno.nl

A survey has been made of the radiation exposure of inhabitants in a small new housing estate in the
Netherlands, where 101 houses are built at about the same time, but according to nine different
designs. The objective of this study was to determine which dwelling characteristics affect the indoor
radon concentrations and the absorbed dose in air. Both components were examined separately for a
period of one year in the crawl space, the living room and a first-floor bedroom, using passive track-etched
and thermoluminescence detectors, respectively. The calculated effective dose to the
inhabitants ranges from 0.5 to 1.3 mSv per year, depending on the design. The houses at the low end
of this range are characterised by a timber frame construction with an air-tight concrete ground floor,
with the remaining floors made of timber and with flue gas desulphurization gypsum inner walls.
Designs constructed according to a corresponding ‘conventional’ building method (concrete floors,
cavity walls made of brick and sand-lime brick), show almost equal radon concentrations and dose
rates. The results indicate that the design has a more pronounced influence on the radiation burden
than the habits and preferences of its occupants.