Assessment of Alpha Doses Received by Spa Workers Due to the Inhalation of 214 Po and 218 Po Radon Progeny

In Morocco spas are more and more frequented by bathers for massages, body treatments, and aromatherapy and hair services, among others. Alpha-activities due to 222 Rn, 220 Rn and their progeny have been evaluated inside spa room atmospheres by means of a technique based on using two types of solid-state nuclear track detectors. 222 Rn and 220 Rn concentrations ranged between (67 ± 5 and 103 ± 7) Bq m -3 and (5.5 ± 0.4 and 9.8 ± 0.7) Bq m -3 for the studied spa rooms, respectively. The influence of ventilation rate in spa rooms on 222 Rn and 220 Rn concentrations has been studied. Alpha-activities due to the attached and unattached fractions of 214 Po and 218 Po radon progeny have been evaluated in various compartments of the respiratory system of spa working personnel. It has been shown that the majority of 214 Po and 218 Po radon progeny are attached to aerosols inside the considered spa rooms. Alpha-doses to the respiratory tract tissues of spa working personnel due to the energy loss of the emitted alpha-particles were evaluated. It has been shown that alpha-doses to the respiratory system of spa working personnel are influenced by exposure time of workers, mass of respiratory system target tissues, and radon concentration inside the studied spa rooms. The largest value of alpha-dose due to the 214 Po and 218 Po radon progeny from inhalation of air by female workers working 2,080 hours per year in the studied spa rooms was found equal to 5.16 mSv y -1 .