PROFICIENCY TESTING ACTIVITIES OF FREQUENCY CALIBRATION LABORATORIES IN TAIWAN, 2009

摘要

In order to meet the requirements of ISO 17025 and the demand of TAF (Taiwan Accreditation Foundation) for calibration inter-laboratory comparisons, the National Time and Frequency Standard Laboratory (TL), playing the role of coordinating lab, has periodically organized the proficiency testing activities to provide opportunities for capability comparisons of domestic frequency calibration laboratories. The latest two activities were performed in 2006 and this year (2009). The "Device under Test" (DUT), together with TL's calibration system, was transferred to each participating laboratory according to a predetermined schedule. The DUT was measured by the participating lab's and TL's calibration systems simultaneously. The measured results from both systems were then analyzed and compared. There were 12 and 15 participating labs joined the activities performed in 2006 and 2009, respectively. All of them were TAF-accredited laboratories. As usual, the En value was used to evaluate a lab's capability of calibrating equipment within its accredited measurement uncertainty. In these two activities, the absolute En values of all labs were smaller than "1," which means their calibration ability was completely qualified. In this paper, the related details of these two activity and the result comparisons between activities in 2