Guardbanding Using Automated Calibration Software

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Guardbanding Using Automated Calibration Software (95.17 KB)

The ISO 17025 standard (“General Requirements for the Competence of Testing and Calibration Laboratories”) requires that measurement uncertainty be taken into account when statements of compliance are made. In other words, when a calibration laboratory calibrates an instrument and produces a calibration certificate indicating that the calibration verification procedure “passed” or “failed”, it is important that, for each test point, the measurement uncertainty be first calculated and then used in the determination of the test result. Guardbanding is a primary technique for assuring compliance with this 17025 requirement. Considerations of efficiency and productivity in calibration laboratories require full automation whenever possible. It is therefore desirable for automated calibration software to include guardbanding capability. This paper describes a flexible, configurable implementation of guardbanding in an automated calibration software system. A number of techniques are discussed, including both table-based and formula-based methods. Facilities for customization of the guardbanding algorithm are presented. A description of generated result data is included.