title: Comparative Measurements of Radon Concentration in Soil Using Passive and Active Methods in High Level Natural Radiation Area (HLNRA) of Ramsar.
abstract: BACKGROUND
  Radon and its daughters are amongst the most important sources of natural exposure in the world. Soil is one of the significant sources of radon/thoron due to both radium and thorium so that the emanated thoron from it may cause increased uncertainties in radon measurements. Recently, a diffusion chamber has been designed and optimized for passive discriminative measurements of radon/thoron concentrations in soil.
  
  
  OBJECTIVE
  In order to evaluate the capability of the passive method, some comparative measurements (with active methods) have been performed.
  
  
  METHODS
  The method is based upon measurements by a diffusion chamber, including two Lexan polycarbonate SSNTDs, which can discriminate the emanated radon/thorn from the soil by delay method. The comparative measurements have been done in ten selected points of HLNRA of Ramsar in Iran. The linear regression and correlation between the results of two methods have been studied.
  
  
  RESULTS
  The results show that the radon concentrations are within the range of 12.1 to 165 kBq/m(3) values. The correlation between the results of active and passive methods was measured by 0.99 value. As well, the thoron concentrations have been measured between 1.9 to 29.5 kBq/m(3) values at the points.
  
  
  CONCLUSIONS
  The sensitivity as well as the strong correlation with active measurements shows that the new low-cost passive method is appropriate for accurate seasonal measurements of radon and thoron concentration in soil.
authors.affiliation: Department of physics, Payame Noor University, Po Box 19395-3697, Tehran, Iran.
authors.forename: B
authors.initials: B
authors.lastname: Amanat
authors.affiliation: Radiation Application School, Nuclear Sciences and Technology Institute, Tehran, Iran ; Iran Nuclear Regulatory Authority, Tehran, Iran.
authors.forename: M R
authors.initials: MR
authors.lastname: Kardan
authors.affiliation: Radiation Research Center, Shiraz University, Shiraz, Iran ; Nuclear Engineering Departments, Shiraz University, Shiraz, Iran.
authors.forename: R
authors.initials: R
authors.lastname: Faghihi
authors.affiliation: Radiation Application School, Nuclear Sciences and Technology Institute, Tehran, Iran ; Iran Nuclear Regulatory Authority, Tehran, Iran.
authors.forename: S M
authors.initials: SM
authors.lastname: Hosseini Pooya
keywords: Passive Detectors; Radon; Ramsar; SSNTD