Objective By organizing and implementing a laboratory proficiency validation plan for air change rate testing, this study aims to explore proficiency testing approaches in laboratory animal facilities, assess the current status of relevant laboratories regarding standard application and test capabilities, standardize air change rate testing methods, and ensure the accuracy and reliability of test results. Methods From September to November 2023, the National Institutes for Food and Drug Control (NIFDC) organized a laboratory proficiency validation plan for air change rate testing in laboratory animal facilities (Plan Number: NIFDC-PT-417). The proficiency testing was conducted on-site and consisted of two parts: a written test and practical operation. The written test was open-book. True/false questions focused on participants' understanding of specific clauses in relevant standards, while application-based questions assessed their ability to handle data processing in simulated testing scenarios. The practical operation was conducted according to the relevant criteria of the China National Accreditation Service for Conformity Assessment (CNAS). Two laboratory animal rooms were prepared as proficiency testing samples using a sample splitting approach. These rooms underwent uniformity and stability testing according to CNAS requirements and were approved. Participating laboratories were required to conduct three tests on each of the two laboratory animal rooms, complete the testing and calculation of air change rate within the specified timeframe, and submit their test result reports and original records. Results A total of 27 laboratories registered and participated in the proficiency testing. All participating laboratories submitted their results within the designated timeframe, and the outcomes of all tested laboratories were rated as satisfactory. Conclusion This proficiency validation program objectively and scientifically evaluates the air change rate testing capabilities of selected domestic laboratories, effectively promoting the overall improvement of testing capabilities in the industry. It provides technical support for regulatory authorities to standardize testing institutions and offers reliable references for the purchase of testing services. Through this activity, it was identified that some laboratories need to further enhance their calibration of instruments and the utilization of calibration results. Future efforts should focus on refining related standards to improve the accuracy and reliability of testing.

Objective Through organizing a proficiency evaluation activity for animal illuminance testing laboratories,to assess the accuracy of testing data from participating laboratories,and to propose suggestions for testing methods.Methods In September 2024,China National Institute for Food and Drug Control(NIFDC)organised reference laboratories to conduct on-site testing through open registration.A total of 35 laboratories participated,completed on-site testing,and submitted their reports.The samples to be tested were two adjacent guinea pig breeding rooms in the NIFDC laboratory animal facility.In order to reduce the impact of room voltage fluctuations on animal illumination,chip on board(COB)light sources powered by regulated power supply were used,and brightness was adjusted by regulating voltage output.Split-level test sample pairs were used to set animal illuminance in both rooms,and the reference laboratories conducted testing according to Laboratory animals——Environment and housing facilities(GB 14925-2023).Each reference laboratory was assigned a 3-digit random code,conducted 2 tests for each breeding room,and submitted an on-site test report,original records,and illuminance meter verification or calibration certificate.WPS Spreadsheet 12.1 was used to summarize data,Grubbs' test(α=0.01)was used to check the data and remove outliers,and SPSS 26.0 software was used for data processing and graph drawing.The median value from each reference laboratory was used as the specified value,the robust standard deviation was used as the uncertainty,the robust z-score method(both intra-laboratory and inter-laboratory z-scores)was used to evaluate the test results from each laboratory,and the factors affecting results were analyzed from aspects of personnel,equipment,and operational environment.Results Under the detection level of α=0.01,no outliers were identified.The specified values for Room 1 and Room 2 were 17.80 lx and 19.00 Ix,respectively.The results obtained from 34 laboratories were evaluated as"satisfactory",while the results from one laboratory were"unsatisfactory".Through analysis of illuminance meter calibration certificates from various laboratories,it was found that some reference laboratories had insufficient calibration points and coverage,which caused test results to fail to accurately reflect the actual illuminance of the facility.Conclusion The present study reveals that factors such as personnel,equipment,and operation environment have different impacts on animal illuminance measurements.The present study concentrates exclusively on animal illuminance in guinea pig breeding rooms,where the testing environment is relatively dim.Future research should focus on the development of more efficient methods for selecting measurement sites,with the combination of illuminance meters equipped with wireless probes and storage functions to enhance testing efficiency.

Objective Through organizing a proficiency evaluation activity for animal illuminance testing laboratories,to assess the accuracy of testing data from participating laboratories,and to propose suggestions for testing methods.Methods In September 2024,China National Institute for Food and Drug Control(NIFDC)organised reference laboratories to conduct on-site testing through open registration.A total of 35 laboratories participated,completed on-site testing,and submitted their reports.The samples to be tested were two adjacent guinea pig breeding rooms in the NIFDC laboratory animal facility.In order to reduce the impact of room voltage fluctuations on animal illumination,chip on board(COB)light sources powered by regulated power supply were used,and brightness was adjusted by regulating voltage output.Split-level test sample pairs were used to set animal illuminance in both rooms,and the reference laboratories conducted testing according to Laboratory animals——Environment and housing facilities(GB 14925-2023).Each reference laboratory was assigned a 3-digit random code,conducted 2 tests for each breeding room,and submitted an on-site test report,original records,and illuminance meter verification or calibration certificate.WPS Spreadsheet 12.1 was used to summarize data,Grubbs' test(α=0.01)was used to check the data and remove outliers,and SPSS 26.0 software was used for data processing and graph drawing.The median value from each reference laboratory was used as the specified value,the robust standard deviation was used as the uncertainty,the robust z-score method(both intra-laboratory and inter-laboratory z-scores)was used to evaluate the test results from each laboratory,and the factors affecting results were analyzed from aspects of personnel,equipment,and operational environment.Results Under the detection level of α=0.01,no outliers were identified.The specified values for Room 1 and Room 2 were 17.80 lx and 19.00 Ix,respectively.The results obtained from 34 laboratories were evaluated as"satisfactory",while the results from one laboratory were"unsatisfactory".Through analysis of illuminance meter calibration certificates from various laboratories,it was found that some reference laboratories had insufficient calibration points and coverage,which caused test results to fail to accurately reflect the actual illuminance of the facility.Conclusion The present study reveals that factors such as personnel,equipment,and operation environment have different impacts on animal illuminance measurements.The present study concentrates exclusively on animal illuminance in guinea pig breeding rooms,where the testing environment is relatively dim.Future research should focus on the development of more efficient methods for selecting measurement sites,with the combination of illuminance meters equipped with wireless probes and storage functions to enhance testing efficiency.