The aim of Task 1.3 is
- to use the 222Rn radon sources developed in Task 1.1 to establish traceable stable radon activity concentrations in reference chambers in the laboratories at BfS, BFKH, IFIN- HH, IRSN, SUJCHBO and METAS,
- to develop calibration procedures for these reference chambers for the radon activity concentration range from 100 Bq/m³ to 300 Bq/m³,
- to use these new reference 222Rn fields to calibrate radon measurement instruments, including those instruments that will then be used in WP5 to validate the traceability of European radon calibration facilities, and to determine their accuracy,
- based on this information, to document a method for the traceable calibration of radon (222Rn) measurement instruments at low activity concentrations (100 Bq/m³ to 300 Bq/m³) with relative uncertainties ≤ 5 % (k = 1).
Alpha-track detectors are the most commonly used radon devices in the world and the most often used for regulation purposes, hence emphasis will be placed on improving their traceability.