Skip to content
English
Go to rudolphresearch.com
  • There are no suggestions because the search field is empty.

Recommended Calibration Interval for NIST-Traceable Quartz Control Plates

Rudolph Research Analytical NIST-traceable calibration standards are manufactured from quartz and are produced to specified requirements for planeness, parallelism, purity, and optical axis alignment. Quartz is inherently optically stable over time. Changes in the optical rotation of a quartz control plate are generally associated with factors such as physical damage, surface scratches, contamination, or optical stress caused by handling or environmental conditions.

Determining the Calibration Interval

The appropriate calibration interval for a quartz control plate should be established by the user based on the requirements of the application and the organization's quality system.

Factors that should be considered when establishing a calibration interval include:

  1. Process accuracy requirements
  2. Regulatory or quality-system requirements
  3. Stability of the calibration standard
  4. Risk to product quality or laboratory results
  5. Historical calibration results
  6. Frequency of use and handling
  7. Operating, storage, and environmental conditions

Because of the inherent stability of quartz, the appropriate calibration interval is primarily influenced by the user's application, risk assessment, calibration history, and quality-system requirements.

Standards and guidance such as ISO/IEC 17025 and ANSI/NCSLI Z540 support establishing calibration intervals based on factors such as intended use, measurement risk, equipment stability, and historical calibration performance.

Rudolph Recommendation

Rudolph Research Analytical recommends an initial calibration interval of 2 to 3 years for NIST-traceable quartz control plates.

This interval should be used as an initial baseline and may be adjusted based on the organization's calibration history, application requirements, risk assessment, and applicable regulatory or quality-system requirements.

Organizations should maintain an appropriate metrology management program and periodically review calibration results to determine whether the established calibration interval remains appropriate.

Additional Considerations

A quartz control plate should be evaluated and, when appropriate, recalibrated before its scheduled calibration interval if it:

  • Is dropped or subjected to physical shock
  • Becomes scratched or otherwise physically damaged
  • Is exposed to conditions that may induce optical stress
  • Produces results that are inconsistent with historical performance
  • Is suspected of contributing to an out-of-tolerance or questionable measurement