Indoor radon in Tunisian spas

¹ Institut Supérieur des Technologies Médicales de Tunis (ISTM), 9 avenue du Docteur Z. Essafi, Tunis 1006, Tunisia
e-mail: labidisalam@yahoo.fr
² Department of Applied Sciences, College of Technological Studies, Public Authority for Applied Education and Training, P.O. Box 42325, 70654 Shuwaikh, Kuwait
email: ds.alazmi@paaet.edu.kw
³ Faculté de Médecine de Sousse. 270, Sahloul II, 4054 Sousse, Tunisia

Received: 25 November 2011
Accepted: 4 January 2012

Abstract

Indoor radon concentrations were measured in four well-known spas of Tunisia using nuclear track detectors. The radon concentrations in these spas were found to be in the range of 19 - 870 Bq.m^-3. The equilibrium factor F between radon and its progeny was found to vary in the range of 0.2 - 0.5, depending upon the ventilation rates within the buildings of the spas. Using the exposure-dose conversion factor, the effective doses to patients and workers were estimated and the dose was found to vary in the range 3.7 × 10^-3 - 12.5 × 10^-3 mSv.y^-1 and 0.45 - 1.5 mSv.y-1 for patients and workers, respectively. These values are well inside the limit recommended for the annual dose limit of 20 mSv.y^-1 for an occupational worker. The radium content in the groundwater of all four spas was measured and the results showed no correlation between the ²²⁶Ra concentration in water and radon concentration in indoor air of the investigated spas.