A revised version of Double Blind Testing of Passive Radon Detectors for the Conference of Radiation Control Program Directors (CRCPD) Committee on Radon (E-25) was released in June, 2013. The report was prepared by Ray Johnson, MS, SE, PE, FHPS, CHP, Consultant, and Craig Harris, Health Physicist.
Read the full report on CRCPD's official website: http://crcpd.org/Radon/BlindTesting/CRCPD%20Blind%20Testing%202013-06-19a%20complete.pdf
Background Information on this Double Blind Project:
Purpose
In a May 2009 report the US Environmental Protection Agency (EPA), Office of Inspector General, determined a need to verify that radon test kits and testers are reliable. To evaluate the performance of passive radon detectors, the Conference of Radiation Control Program Directors (CRCPD) issued a call for proposals in the spring of 2009 to seek a contractor for conducting double blind testing of radon detectors available to the generalpublic. A contract was awarded to Dade Moeller and Associates (Dade Moeller) in August 2009 for a double blind testing project to be coordinated by the CRCPD Committee on Radon (E-25).
General Conclusions
While this study indicates that a few laboratories need attention on the quality of their measurements, it seems reasonable to conclude that homeowners can generally have confidence in the accuracy and reliability of radon laboratory measurements in the United States. For continuing confidence in radon measurements it would also seem prudentto conduct double blind studies of radon laboratories on a regular basis. However, a double blind study can only provide an indication of
performance as a snapshot at the time of the study. The best assurance of ongoing radon testing re
liability is for individual laboratories to maintain a rigorous quality assurance program which includes monthly spikes, blanks, and duplicates, and daily verification of measurement quality by plotting control charts of check source and background readings. For making good decisions for radon mitigation, the greatest source of uncertainty most likely does not involve laboratory measurements, but rather the placement of radon detectors in homes, weather conditions, and occupancy factors. While laboratories can carefully control their analytical procedures, they cannot control how radon detectors are used or under what conditions.