Radon in (Greek) workplaces GREECE

Transcription

1 Radon in (Greek) workplaces GREECE Maria Kolovou Department of Environmental Radioactivity Control

2 Measurement of radon Radon measurements are performed according to the terms of ISO Passive: Solid state nuclear track detectors -CR 39 Discharge of polarisedsurface inside an ionization chamber -Electret Active: Alpha guard SARAD All data are saved in an Ingres 9.2 database Accreditation according to the terms of ISO 17025

3 Existing legislation Decision 1014(ΦΟΡ) 94/ Radiation Protection Regulations Specifically, as regards exposure due to the presence of radon and its daughters at the workplace, the following rules shall apply: 1. Workplaces at which the average annual total radon concentration (corresponding to an annual working time of 2000 hours) is less than 400 Bq/m3 shall be exempted from further control and radiation protection measures. 2. In workplaces at which the average annual total radon concentration (corresponding to an annual working time of 2000 hours) is greater than 400 Bq/m3 and less than 1000 Bq/m3, the possibility of reducing the above concentrations using appropriate technologies shall be investigated. These workplaces shall be defined as supervised areas and the radiation protection measures taken must be approved by GAEC. 3. Workplaces at which the average annual total concentration of radon (corresponding to an annual working time of 2000 hours) is greater than 1000 Bq/m3 and less than 3000 Bq/m3 shall be defined as controlled areas and the practices in question must be authorized by GAEC; the radiation protection measures taken must be approved by GAEC. 4. The average annual total concentration of radon at the workplace may not exceed 3000Bq/m3foranannualworkingtimeof2000hours.

4 Measurements of radon in schools Radon and gamma dose rate measurements were performed in 512 schools in 8ofthe13regionsofGreece. The distribution of radon concentration was well described by a lognormal distribution. Most (86%) of the radon concentrations were between 60 and 250Bq/m 3 withamostprobablevalueof135 Bq/m 3. The arithmetic and geometric means of the radon concentration are 149 Bq/m 3 and 126 Bq/m 3 respectively. The maximum measured radon gas concentrationwas958 Bq/m 3 Only in a small fraction (about 2.7%) of schools, the European Commission actionlevel(400 Bq/m 3 )wasexceeded. Thevalueof200 Bq/m 3 wasexceededatabout17%oftheschools.

5 Measurements of radon in schools The school with measurement over 400 Bq/m3 were in Ksanthi and Ikaria Ikaria Firstmeasurement~1500Bq/m 3 Iris expert installed an active system Now200Bq/m 3 Ksanthi 9schoolshadmeanradonconcentrationabove400Bq/m 3. From continuous radon gas measurements in the school with a relative higher radonconcentration(958bq/m 3 )theradonconcentrationintheschool,during thehoursofthepresenceofteachersandscholars,foratimeperiodofabout2 weeks was 104 Bq/m 3. The mean radon concentration for the same 2 weeks was700bq/m 3

6 Measurements of radon in underground workplaces METRO 2004 main metro stations Today repeat due to reduction to ventilation main lignite mine (Kardia) of the electric company in kozani(max 200 Bq/m 3 ) TVX Hellas MavrePetres(galena, sphalerite) ( Bq/m 3 ) MademLakkos(pyrite) ( Bq/m 3 ) Olympiada(gold) ( Bq/m 3 ) Skouries(gold) (150 Bq/m 3 at 50m)

7 Measurements of radon in spas InGreecetherearemorethan200spasbutonly70areactive In 2009 legislation obliged all to perform a survey (including radiological) in order to be categorized 11 were categorized as radon spas Spa Min (Bq/l) Max(Bq/l) Ikaria(4) Kamena Vourla(3) Loutraki Korinthias(3) Edipsos In 2011 legislation for occupational exposure Study in progress InEdipsoinworkingplacesmaxwas195Bq/m 3

8 Measurements of radon in public buildings Region Min (Bq/m 3 ) Max (Bq/m 3 ) Concert hall Athens Hospitals Athens, Thessalonica, Ioannina, Patra Monasteries Mount Athos Banks 20 around Athens Foundation for Research and Technology Crete Army facilities Around Greece Tourist caves Crete

9 THANK YOU Greek Atomic Energy Commission P.O Box Agia Paraskevi 15310, Athens T: F: E: facebook.com/eeaegr twitter.com/#eeaegr 9