Quality Control and Evaluation Method for Analysis Process of ⁹⁰Sr in Environmental Sample

In order to confirm lab’s testing ability of ⁹⁰Sr in environmental samples, ensure test results’ accuracy and reliability, quality control activities such as internal and external tests are needed normally. The defects of the old quality control and evaluation methods for the analysis of ⁹⁰Sr were discussed. The evaluation method of quality control chart, the value of E_n method, Z-score method and critical value method were exhaustively studied, and a systematic discussion for the internal and external quality control and the evaluation method for analysis process of ⁹⁰Sr in environmental sample with example was made. As for internal quality control and evaluation methods, blank samples can be evaluated by the quality control chart and judgment limit, parallel double samples can be evaluated by the critical value method, spiked blind sample and radiochemistry recovery rate test can be evaluated by the value of E_n method, and the evaluation of comparison between personnel can be evaluated by the critical value method, value of E_n method, Z-score method and t test method. As for external quality control and evaluation methods, the critical value method, value of E_n method and Z-score method can be used for the evaluation of the measurement audit, and the capacity verification can be evaluated by the value of E_n method and Z-score method.