Comparison of calibration facilities for the radon activity concentration
Project Description
The comparison is an important tool of quality assurance in the radon activity concentration metrology. Since no direct comparisons of radon reference atmospheres are possible, this comparison uses a radon monitor as a comparison device. The radon monitor is calibrated in the reference atmosphere of each participating radon calibration institution at given radon activity concentrations (1 kBq/m3, 3 kBq/m3, 10 kBq/m3 ) due to the standard calibration procedure at this institution. All participating radon calibration institutions have to qualify themselves by a traceability chain to national / international standards and an implemented quality assurance system. As a result of these calibrations, the calibration factors and their corresponding uncertainties are compared and discussed. This procedure was successfully tested already in 2001-2002. It will provide a solid metrological basis for radon activity concentration measurements, which gained importance due to the Euratom regulation (96/29).
Radon monitor (comparison device) was purchased in 2000 by PTB, it is tested and available.
Final Report 2005-01-31
Since no direct comparisons of radon reference atmospheres are possible, this comparison has used a radon monitor as a comparison device. The radon monitor has been calibrated in the reference atmosphere of each participating institute at given radon activity concentrations (1 kBq/m3, 3 kBq/m3, 10 kBq/m3 ) due to the
standard calibration procedure at this institute.
Status:
- There have been no major problems
- Everything was done according the technical protocol. No delays were observed
- All information about the traceability chains were complete at the beginning of the measurements in October 2002
- All measurements of the 12 participants have been completed until March 2004
- Ten of twelve result reports have already been received at PTB. The collection of results was finished in May 2004
- The comparison meeting was held at PTB Braunschweig at June 14th - 15th
- Draft A was presented and distributed during the meeting
- Draft B completed 2005-01-20