Radon and thoron doses in kindergartens and elementary schools

Abstract

Exposing the Raduet Rn-Tn solid-state nuclear track detectors, radon (Rn: (222)Rn) and thoron (Tn: (220)Rn) activity concentrations have been measured in 7 kindergartens and 18 elementary schools in Slovenia. Diurnal variations of both gases were monitored using a Rad7 device. The Rn concentration was in the range from 145 to 794 Bq m(-3) in kindergartens and from 70 to 770 Bq m(-3) in schools, and the Tn concentration was in the range from 21 to 73 Bq m(-3) in kindergartens and from 4 to 91 Bq m(-3) in schools. The Tn versus Rn concentration ratio varied from 0.02 to 0.83. Monthly effective doses due to radon and its decay products ranged from 109 to 600 μSv month(-1) in kindergartens and from 21 to 232 μSv month(-1) in schools, and those due to thoron and its decay products ranged from 3.8 to 13.3 μSv month(-1) in kindergartens and from 0.29 to 6.62 μSv month(-1) in schools. The contribution of thoron to the total effective dose was from 1.3 to 11 % in kindergartens and from 0.4 to 17 % in schools.

Children’s Exposure to Radon in Nursery and Primary Schools

“…Indoor mean radon concentrations reported in recent literature for nursery schools from Italy [ 24 ], Bulgaria [ 26 ], Slovenia [ 25 ] and Czech Republic [ 27 ] were usually higher than those found in the present study, in both school microenvironments in the Porto and Bragança districts, which in turn were higher than those found in nursery schools from Saudi Arabia [ 22 ] and Poland [ 10 ].…”

“…On the other hand, indoor radon concentrations found in schools from the Porto district were lower than the majority of those found in recent literature, except when comparing with the results from Turkish [ 15 ], Canadian [ 17 ] and Pakistani schools [ 18 , 19 ]. Indoor radon concentrations found in schools from the Bragança district were higher than the majority of the ones reported in the literature, except for those in Bulgaria [ 26 ] and Slovenia [ 25 ], which enhance the concerns about the results here found for the Bragança district.…”

“…Considering the latter and as far as the authors’ knowledge goes, in the last five years 19 studies regarding radon in indoor air of nursery and primary schools can be found. The majority of them were only focused on primary schools [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ], while others also considered nursery schools [ 10 , 22 , 23 , 24 , 25 , 26 ] and some others only considered nursery schools [ 27 , 28 ]. The extent of the studies varied considerably from study to study.…”

“…The extent of the studies varied considerably from study to study. There are studies (surveys) that included a considerable number of nursery and primary schools of a particular country or region [ 14 , 16 , 27 ] and others studied only a limited number of buildings [ 25 , 26 ]. In the latter cases, a representative number of buildings was selected taking into account selection criteria that varied from case to case, like a comparison between two different cities [ 10 ] or a comparison between urban and rural contexts [ 18 ].…”

Long-term measurements of radon, thoron and their airborne progeny in 25 schools in Republic of Srpska

“…As mentioned earlier, the C Tn strongly depends on the distance from the wall, and such dependence arises for C Tn /C Rn as well. By comparison, in a survey of 18 Slovenian primary schools, where detectors were placed at 1 m distance from the wall, this value of C Tn /C Rn was lower, namely in the range of 0.02e0.82 (Vaupoti c et al, 2012).…”