A chamber to test the response of radon detectors to changing environmental conditions

Radon risk assessment is carried out with accurate measurements with active or passive instrumentation. All radon detectors must be calibrated and tested using a radon chamber containing a known concentration of radon produced by specific sources of 226Ra. Some of the chambers can also be used to test the response of detectors as a function of environmental conditions. In this case, it can be inferred a calibration curve with respect to changing of the parameter considered. For this aim, a new chamber radon was designed and realized to perform both calibration of instruments and to study the detector response in a large range of variation of the environmental parameters (pressure, 700 - 1100 mbar; temperature, 5-50 ◦C; humidity, 10-90%). The experiments conducted to study the influence of environmental parameters on the detector response, in terms of variation of radon concentration and equilibrium factor, have shown flexibility and ease of use of the chamber.