Filtration approach to mitigate indoor thoron progeny concentration

• Autorzy: Wang J. , Meisenberg O. , Chen Y. , Karg E. , Tschiersch J.
• Konferencja: Proceedings of the International Conference "Radon in Environment" 10-14 May 2009, Zakopane Poland
• Języki publikacji: EN

Abstrakty

EN

This study investigates filtration of air as potential mitigation method of thoron progeny exposure. The experiments were conducted in a model room (volume 7.1 m3) which was equipped with a pump and an HEPA (high efficiency particulate air) filter. Filtration at a rate of 0.2, 0.4, 0.5 and 0.8 h–1 during 88 h proved an effective practice in reducing the total indoor thoron decay product concentration. The results indicate that 0.4–0.8 h–1 filtration rate had almost the same filtration efficiency in decreasing the total thoron EEC (equilibrium equivalent concentration) by 97 per cent while 80 per cent of total thoron EEC were reduced by 0.2 h–1 filtration rate; meanwhile, the unattached thoron EEC rose significantly by 190, 270, 290 per cent, respectively under 0.4–0.8 h–1 filtration rate, whereas 0.2 h–1 filtration rate increased unattached thoron EEC by 40 per cent. The aerosol number size distribution variation reveals that filtration operation removes smaller particles faster or earlier than the larger ones. The annual effective dose calculated was reduced by 91–92 per cent at a filtration rate of 0.4–0.8 h–1 while 75 per cent reduced at 0.2 h–1 filtration rate after 88 h filtration process.

Słowa kluczowe

EN

filtration; thoron progeny; potential alpha energy concentration (PAEC); equilibrium equivalent concentration (EEC); mitigation

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2010
• Tom: Vol. 55, No. 4
• Strony: 445--450
• Opis fizyczny: Bibliogr. 26 poz., rys.

Twórcy

autor

Wang J.

autor

Meisenberg O.

autor

Chen Y.

autor

Karg E.

autor

Tschiersch J.

• Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, PR China and Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Radiation Protection, 1 Ingolstädter Landstr., 85764 Neuherber,

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