Development of a continuous radon concentration monitoring system in underground soil

Author

Yamamoto, S. ; Tarutani, K. ; Yamasoto, K. ; Iskandar, D. ; Iida, T.

Author_Institution

Kobe City Coll. of Technol., Japan

Volume

48

Issue

3

fYear

2001

fDate

6/1/2001 12:00:00 AM

Firstpage

391

Lastpage

394

Abstract

A continuous radon (Rn-222) concentration monitoring system for use in underground soil was developed and tested. The system consists of a 19-mm-diameter, 1100-mm-long detector assembly and a microprocessor based data logger. A small volume chamber is installed at the tip of the detector assembly. A thin ZnS(Ag) scintillator film inside the chamber and a photomultiplier tube (PMT) detect alpha particles from radon and its daughters. When the system is in measurement, the detector part is buried into underground soil. An energy resolution of approximately 70% full width half maximum (FWHM) was obtained for 5.5 MeV alpha particles from Am-241. Both the rise time and fall time for the system were measured to be approximately 1-2 h. Temporal variations in underground radon concentration at different depths were investigated simultaneously using four sets of the developed system. The results confirmed that the developed system is useful for continuous measurement of radon concentration in underground soil

Keywords

alpha-particle detection; natural radioactivity hazards; photomultipliers; radiation monitoring; soil; solid scintillation detectors; 5.5 MeV; ²²²Rn; FWHM; Rn; ZnS(Ag) scintillator film; ZnS:Ag; alpha particles; continuous Rn concentration monitoring system; energy resolution; photomultiplier tube; underground Rn concentration; underground soil; Alpha particles; Assembly systems; Detectors; Energy resolution; Microprocessors; Monitoring; Photomultipliers; Soil measurements; System testing; Time measurement;

fLanguage

English

Journal_Title

Nuclear Science, IEEE Transactions on

Publisher

ieee

ISSN

0018-9499

Type

jour

DOI

10.1109/23.940086

Filename

940086