title: Development and characterisation of a silicon PIN diode array based highly sensitive portable continuous radon monitor.
abstract: This paper discusses the development and characterisation of a portable and highly sensitive continuous radon monitor (CRM) based on an array of in-house developed silicon PIN diode detectors. The development of this system was initiated in view of the limitations of the available similar radon measurement systems with regards to low sensitivity. The system utilises a hemispherical metal chamber (1 L capacity) for active air sampling. A quantitative estimation of radon concentration is carried out through alpha spectroscopy of electro-deposited (222)Rn decay products on the detector surface. The system was successfully tested and characterised in laboratory conditions. The characterisation experiments included optimisation of sensitivity, calibration with respect to linearity and a study of the influence of humidity on its performance. The novel PIN diode array design yields a high sensitivity of 1.76 ± 0.003 counts h(-1)/(Bq m(-3)) at a relative humidity level of 10% in the sampled air, which is more than two times as high as that reported for similar commercial systems. This instrument displayed a minimum detectable activity level of 0.80 Bq m(-3).
authors: Radiation Safety Systems Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India.
authors: P
authors: P
authors: Ashokkumar
authors: B K
authors: BK
authors: Sahoo
authors: Anand
authors: A
authors: Raman
authors: Y S
authors: YS
authors: Mayya
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D004867:Equipment Design; D011834:Radiation Monitoring / Q000295:instrumentation*; D011886:Radon / Q000032:analysis*; D012825:Silicon
chemical_list: D000396:Air Pollutants, Radioactive; D011886:Radon; D012825:Silicon