自然環境用ラドン娘核種モニター

• 児島 紘

  東京理科大学理工学部

• 阿部 史朗

  放射線医学総合研究所環境衛生研究部

書誌事項

タイトル別名

• An apparatus for environmental monitoring of short lived radon daughters.

抄録

We performed an attempt for application of a radon daughter monitor which enabled the measurements of individual activity concentrations of short lived radon daughters in a natural environment. The monitor was fundamentally based on a filter method with gross counting, which was refered to as Tsivoglou-Thomas method; the radon daughters in the air were sampled on a membrane filter and α rays from RaA and RaC' in the collected daughters were counted over three time intervals. By comparing these counting values with theoretical decay characteristics, the activity concentration of each of three nuclides (RaA, RaB, RaC) was obtained.<br>The precision of the assessment of activity concentration in this method depends on several parameters related to the measuring conditions. Therefore, to enable the most precise assessment of the activity, the values of these parameters were determined, based on the calculation of error propagation. The calculation showed that the most sensitive parameters to the assessment were a flow rate (L) of sampling air, a total counting time interval (t₁+t₂+t₃) and a waiting time (t₀) which is a time interval from the end of the sampling period to the start of count. Based on the results, we determined the values of these parameters as follows: sampling time=10min, t₀=10sec, first counting time interval=4min, and second and third counting interval=27min.<br>In order to confirm the validity of the monitor, the preliminary measurements were carried out indoor and outdoor. The result offered the possibility of using the monitor to automatically assess the activity concentration of short lived radon daughters.

収録刊行物

• 保健物理

  保健物理 21 (3), 167-174, 1986

  日本保健物理学会

キーワード

• apparatus
• environment
• radon
• radon daughters
• filter method

詳細情報

• CRID: 1390001204289922688
• NII論文ID: 130000793037
• NII書誌ID: AN00228458
• DOI: 10.5453/jhps.21.167
• COI: 1:CAS:528:DyaL2sXit1anu7w%3D
• ISSN: 18847560
• ISSN: 03676110
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可