Calibration verification is used to determine which of the following?

• A. It recalibrates the instrument using fresh buffer standards.
• B. Calibration verification confirms instrument performance remains within acceptance after calibration by running a known standard and comparing to expected values at intervals or after a set number of samples.
• C. It measures only the initial calibration accuracy on first setup.
• D. It is performed only when changing measurement units.

Answer: (B)

Calibration verification is a quality control step to confirm that an instrument remains accurate after it has been calibrated. It works by running a known standard and comparing the measured value to the expected value, at defined intervals or after a set number of samples. This check helps detect drift, wear, or other changes that could affect results, ensuring the instrument stays within the accepted tolerance between calibrations. If the measured standard falls within tolerance, the instrument is deemed to be performing correctly; if not, it indicates that recalibration or maintenance is needed. This isn’t about recalibrating with fresh standards, nor is it limited to the initial setup or tied to changing measurement units.