真空計測における Japan Calibration Service System：計量法に基づく校正事業者登録制度（JCSS）への取り組み，「誤差」から「トレーサビリティー」と「不確かさ」へ

This article describes the reason why ULVAC, Inc. tried to become the JCSS calibration Lab, and also describes the advantage to our vacuum gauge users. When operating ISO/IEC 17025 and getting traceability of measurement we needs to understand the concept of uncertainty of measurement. Understanding the difference of the concept of “measurement error” and “uncertainty of measurement” leads to understanding the concept of the traceability of measurement.