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RADIOACTIVITY IN BUILDING MATERIALS: EXPERIMENTAL METHODS, CALCULATIONS AND AN OVERVIEW OF THE ITALIAN SITUATION

S. Risica* + , C. Bolzan**, and C. Nuccetelli*
*Physics Laboratory, National Institute of Health, (Istituto Superiore di Sanità), Viale Regina Elena
299, 00161 Rome, Italy
**Fellow of the Physics Laboratory, National Institute of Health + Corresponding author: Tel: +390649902203, fax: +390649387075, e-mail: serena@iss.it

First, models (room models) published in the international literature allowing the exposure to
gamma radiation indoors due to building materials to be assessed are reviewed and discussed. For
one of them, a sensitivity analysis regarding the effect of changing the parameters (e.g. dimensions
of the room, thickness and density of the walls, etc.) used in calculations is performed. Second, a
method is proposed for calculating the activity concentration in the walls of a room using: a) the
measured absorbed dose rate in air in the room; b) the contributions of natural radionuclides ( 238 U, 232 Th and 40 K) to the absorbed dose rate in air assessed by means of gamma spectrometry indoors;
c) the specific dose rate (nGyh -1 per Bqkg -1 ) of natural radionuclides, for the chosen room
geometry, calculated with the room model. Finally, published data on radioactivity concentration in
Italian building materials is reviewed. This data is used to assess the marketing impact of
introducing limitations on the use of these materials.
Keywords: radioactivity, room model, building materials, activity concentration indexes.