Study on the deposition velocity of .sup.222Rn/.sup.220Rn progeny at varying environmental conditions

• Published in: Journal of radioanalytical and nuclear chemistry 2022-12, Vol.331 (12), p.5547
• Main Authors: Prajith, R, Rout, R. P, Mishra, R, Jalaluddin, S, Sapra, B. K
• Format: Article
• Language: English
• Subjects: Analysis; Environmental quality; Humidity
• ISSN: 0236-5731
• DOI: 10.1007/s10967-022-08671-w

Deposition of the .sup.222Rn (radon) and .sup.220Rn (thoron) progeny on surfaces is one of the important processes that reduces the progeny activity concentration and hence inhalation dose in the indoor as well as occupational environment. Deposition of .sup.222Rn/.sup.220Rn progeny on surfaces is characterized by the term effective deposition velocity ( [Formula omitted]) which is highly influenced by parameters like air velocity, aerosol concentration (Z) and Relative Humidity (RH) etc. prevailing in any real indoor or occupational environment. In the present study, behavior of [Formula omitted] of both .sup.222Rn and .sup.220Rn progeny for varying environmental conditions were studied by simulating these conditions in an 8 m.sup.3 calibration chamber. It was observed that both .sup.222Rn and .sup.220Rn progeny behave in a similar manner with respect to the environmental parameters. With increase in air velocity, [Formula omitted] of both .sup.222Rn and .sup.220Rn progeny was found to be increased, whereas, with increase in Z and RH, [Formula omitted] was observed to be decreased. The experimentally obtained values of [Formula omitted] were compared against the theoretical model calculation which showed good agreement. Measurement of [Formula omitted] was also carried out in an occupational environment with varying humidity conditions and was found to agree well with the theoretical as well as the experimental values of [Formula omitted] in controlled calibration chamber.