//,**0. +2 - +, + +, + + + +1 3 -* +2 + +1 Radon Concentration in Air and Water and Tentative Dose Estimation in A Hot Spring Hotel of Gifu Prefecture Michikuni SHIMO +,ShinoOYAIZU +,ShinjiTOKONAMI,,KaoriKITAMURA +, Kazutaka EJIRI + and Kazuyuki MINAMI + + Fujita Health University, School of Health Sciences, Radon Research Group, National Institute of Radiological Sciences Abstract Measurement of radon concentration in indoor air and in spring water and bath was performed in a hot-spring hotel to estimate the human dose due to radon decay products. Radon concentration was -*1/ Bq/m - for indoor air, -/** Bq/L for spring water and,0* Bq/L for bath water. The tentative diurnal dose was estimated from calculation to become /.- msv for staying person and..+ msv for hotel stu#, respectively. The tentative annual dose was calculated from the diurnal dose to become 0* msv for staying person and,.2 msv for hotel stu#, respectively. These estimated doses are about, times higher comparing with world mean dose due to natural radon. It is concluded that these values are able to be ignored for consideration of human health. Key words : Hot-spring hotel, Radon concentration, Indoor air, Hot-spring water, Tentative dose estimation : 177
178 +,**+,.. msv,,, Rn,,* Rn + l +* Bq +33, + l,,, Rn 1. Bq,,0 Ra + + mg,,0 Ra,,, Rn,,+ +, / Fig. + / +* -* 3 +, +* ++, : + 3,., +* -+ -1
//,**0 179 Fig. + Measuring room in air and setting position of Rn-Tn monitor. Fig., Radon concentration in indoor air. + + +, - 1* -1-1 Fig.,,,,* m + +, +,
180 Table + Radon concentration in spring water and bath water Spring water & bath water Rn in Bq/L Ref4 Spring water Rn in Bq/L Spring water Water of bathtub for male + Water of bathtub for male, Water of bathtub for female + Water of bathtub for female, Mean of bathtub water -5/**-1 +/*- 243*41-0*0 +.*42,0*/.51** (Aug +0, 3/), -5.** (Oct,/, *,) -53** (Apr,, *-),,5.** (Aug,-, *-) -53** (Sep,., *-), + +,* +/ +* -* +, +, +* -* +0 -*,* -+ 2,, - Table + - -+ + Fig. - -* + - + -, D msv,*** DK T F Q K msvbq hm - T + + h F *.. *./,**+ Q Bqm -
//,**0 181 Fig. - Diurnal occupancy time, (a) Stay person, (b) Hotel stu#. P Da msv BRER, +333 D DaP D P +*. P +*. + Dw msv BRER, +333 DwKw W Qw Kw -./+* 0 msvbq, W + m - y,qw Bqm - + +** ml -,.+ L + + W + +2* ml -.2 L T
182 Fig. - + +..+ / / 3Bqm - /. Bqm - / /.2,*** ;,*** *./, *.0+.. 0.- Bqm -,*** + Yamasaki et al., +33/.,, Table, + /.- msv,..+ msv *./,,.1++ msv,,2., msv.- 2 2 + +,0* BqL Table - *.*.0 msv Table, ++**.. Table + 0, *.1+.. +* /,0** BqL,**, ++,3 IM
//,**0 183 Table, Parameters and diurnal dose and total diurnal dose (a) Stay person Dose conversion factor [msv/(bq h m - )] Diurnal occupancy time [h] F value [] Radon concentration in indoor air [Bq/m - ] Diurnal dose [ msv] Guest RM Dining RM Dressing RM Bath RM Outdoor (sum) +.4/,4* *4/ *4/ 04/,. *4/ /-+* /3 2 /. 3 /. 3 04-,41*4/ *4*0 +4**4, +4**4, *4+2 /4-*40 (b) Hotel stu# Dose conversion factor [msv/(bq h m - )] Diurnal occupancy time [h] F value [] Radon concentration in indoor air [Bq/m - ] Diurnal dose [ msv] Guest RM Dining RM Dressing RM Bath RM Outdoor (sum) +*4/ 24* +4* *4/.4*,. *4/ /-+* /3 2 /. 3 /. 3 04-,4* +41*4, *4,*4*- *4+*4*, *4++.4+ Table - Diurnal dose due to radon emanated from bath water Case Radon content in bathtub [Bq/L] Dose [ msv] Remarks (values of factor in Eq4 (+) and (,)) (+) (,) Mean of (+) and (,) +/* -0,0* *4*,1 *4*00 *4*.0 P+*.,K,T*4/, F P+*.,K,T*4/, F P+*.,K,T*4/, F + +2* ml +,., msv *.1+.. +./-.+ msv + -.0 msv -,0. msv./ + 1./ msv
184 Table. Dose due to radon Stay person Hotel stu# Mean value in Japan Diurnal dose 140 msv Rn in air /4. Rn in water *4*.0 Drinking,4,.4+ msv +4, msv Annual dose Rn concentration in Japan Annual occupation time (UNSCEAR,**+) *40 msv : - months stay,42 msv : one year stay +4/ msv - msv (used for upper column) Indoor : +/40 Bq/m - Outdoor : 04- Bq/m - Indoor : 1*** h Outdoor : +10* h 20,.* 3*,/* 1* -* +..+ msv /*,** + - *..- msv Sanada et al., +333 *./1 msv *.+0 msv*..+ msv + +,.2 msv + +./ msv -./ Table. + + +.,0 msv - /* +,.,, UNSCEAR,,**+,**..0 + -,+* 0 msvbq hm -,**+ -1* Bqm - F + 03 msv 1.0 msv
//,**0 185 F *.. +33/ ; Tokonami et al.,,**. / -*1/ Bqm -, -,/** BqL,,2* BqL + /.- msv - + *.0* msv +,.2 msv +..+ msv + +./* msv 3*,/* /*,** +.,0 msv -,., +.- *..- msv +.. 0./ -./, Board on Radiation E#ects Research (BRER ; +333) : Risk Assessment of Radon in Drinking Water, CLS/NRC Report, National academy Press.,*** : No.,1 /.0-. +33, :,*** :,*,3. UNSCEAR ;,**+ :,*** Sanada, T., Fujimoto, K., Miyano, K., Doi, M., Tokonami, S., Uesugi, M. and Takata, Y. (+333) : Measurement of Nationwide Indoor Radon Concentration in Japan, J. Env. Radioact.,./, +,3+-1.,*** : +,+3.
186,*** : No.,1 ++2+,-. Shimo, M., Sugino, M. and Hatano, H. (,**-) : Measurements of Radon Concentration in Water of Campus, Dormitory and Student Home in South area of Gifu Prefecture and Northwest area of Aichi Prefecture, J. Journ Health Phys. -2 (-),,0+,00.,**. : Proc. / th Workshop on Environmental Radioactivity, Ed. Miura T., 203-. Tokonami, S., Zhuo, W., Ryuo, H., Yonehara, H., Yamada, Y. and Shimo, M. (,**-) : Instrument Performance of A Radon Measuring System with The Alpha Track Detection Technique, Radiat. Prot. Dosim. +*-, 031,. Tokonami, S., Sun, Q., Akiba, S., Zhuo, W., Furukawa, M., Ishikawa, T., Hou, C., Zhang, S., Narazaki, Y., Ohji, B., Yonehara, H. and Yamada, Y. (,**.) : Radon and Thoron Exposure for Cave Residents in Shanxi and Shaanxi Provinces, Radiat. Res., +0,, -3*-30. Yamasaki, T., Guo, Q. and Iida, T. (+33/) : Distributions of thoron Progeny Concentration in Dwelling, Radiat.Prot. Dosim. /3, +-/+.*. +33/ : KURRI-TR-.+1 1/3+. Zhuo, W., Tokonami, S., Yonehara, H. and Yamada, Y. (,**,) : A Simple Passive Monitor for Integrating Measurements of Indoor Thoron Concentration, Rev. Sci. Instrum., 1- (2),,211,22+. +,,, Rn,,* Rn Zhuo et al.,,**, ; Tokonami et al.,,**- -/ mm, // mm, ++* cm -,,* g CR-3 a // +, mm. CR-3 0 3* +* mm CR-3 /* mm,
//,**0 187 Q RnCF Tn,N RnBCF Tn+N TnBTCF Rn+ CF Tn,CF Tn+ CF Rn, Q TnCF Rn,N RnBCF Rn+N TnBTCF Tn+ CF Rn,CF Rn+ CF Tn, N Rn : trackscm, N Tn : trackscm, Q Rn : kbqm - Q Tn : kbqm - CF Rn+ : trackscm, kbqm - h,., CF Tn+ : trackscm, kbqm - h*.+ CF Rn, : trackscm, kbqm - h,., CF Tn, : trackscm, kbqm - h+.- T: h B:CR--3 trackscm, A-+, A-,,,**- /** ml DPO, g, POPOP /* mg - ml +1 ml,** - ml +1 ml,** -, P /,,, Rn,,, Rn Q Bq Q QC f/ e V T*.**0, C f A-- C:/ e : V: l T: s f:, +.+/ +