MS-QA_06-2019 rev5

ANSI/AARST MS-QA 2019 15 Radon Measurement Systems Quality Assurance Field Operations—EIC, Alpha Track and Charcoal Adsorption 5 QC FOR FIELD OPERATIONS USING EIC, ALPHA TRACK DETECTORS (ATD), and CHARCOAL ADSORPTION DEVICES (CAD) METHODS This section applies to the field measurement operations of EICs, ATDs and CADs, but does not include their analyses. The purpose of QC procedures is to provide documentation of validity and to ensure measurement results are defensible; the results of QC checks must be recorded, evaluated and used to maintain and improve measurement quality. Field operations for these methods require QC checks, including: 1. Detector condition checks 2. Blanks 3. Spikes 4. Duplicates 5.1 Field Operations (EIC, ATD, CAD)—Required Detector Condition Checks Standard operating procedures are to include checks for the integrity of the detector and package at the beginning of each test before it is opened and at the end of each test when it is closed. Any concerns are to be logged and relayed to the QP responsible for data validation of test results, to include: a) For CAD methods: poor closure of the charcoal container; damaged packaging; loose stickers, tape, lids and caps; or other conditions that may affect measurement; b) For ATD methods: poor closure of the ATD, damaged packaging, loose closure of a sticker or cap, or other conditions that may affect measurement; and c) For EIC methods: poor closure of the chambers, a loose cap or spring or debris on the electret surface, evidence of mechanical shock, or other conditions that may affect measurement. 5.2 Field Operations (EIC, ATD, CAD)—Required Blanks Informative advisory — Blanks are devices deployed to verify and document the absence of effects on the measurement result from sources other than the air being tested, and their records are important components of defensible data. It is vitally important to deploy blanks in a timely manner because an investigation of any failed blank may result in invalidating all recent field measurements or entire inventories of stored detectors due to interferences introduced during storage or shipping. 5.2.1 Field Operation Blanks—Frequency and Procedures Users of EIC, ATD, and CAD detectors are responsible for setting aside at least 5% of the number of measurements or a maximum required of 25 per month to be used as blanks . If using detectors with different configurations, even when from the same manufacturer, the same requirement applies for each different configuration, including differences in both the design of the detector as well as the type and source of the sensitive material used in the CADs and ATDs (Note—Section 7.4 Lab Quality Control of Detector Materials describes quality tracking for laboratories.) Procedures related to detector packaging and shipping, such as opening and immediately closing detectors, shall be done in conformance with manufacturer recommendations for handling blanks . Informative advisory —When blanks are processed at an independent analysis laboratory, the deployment period represented to an independent analysis laboratory should be consistent with that of other deployed detectors or as stated by the manufacturer as the optimal deployment period for that detector.