AARST_Radon_Reporter_July_2023

THE RADON REPORTER | 17 RESEARCH FIGURE 5. INDIVIDUAL CONCENTRATION MEASUREMENTS BY EACH OF THE THREE TRAVELING AGS WITH THE 4TH (LOANED FROM THE US EPA LAS VEGAS) AG IN A VERY LOW CONCENTRATION ENVIRONMENT (DATE AXES OF DIFFERENT SCALES). As shown in Figure 5, the background measurements showed consistency and exhibited no evidence of background buildup in the three AlphaGUARDs relative to the fourth, in the final very low concentration outdoor environment. The overall conclusions are clear: radon calibration chamber engineers and operators successfully manage radon emanation rates, air flow and leakage, as well as their ownmeasurement systems, and report calibration concentrations with an impressive degree of accuracy. The participating NRPP secondary calibration facilities in the US can be confident that their systems accurately correspond with those in Canada, Sweden, the United Kingdom, Australia, Spain, and the Czech Republic. These intercomparisons need to be repeated periodically, but for now, American radon measurement providers can be assured that if they use an NRPP listed calibration facility, their results can be used with confidence.