Do Not Use Laboratory Glassware with Faded or Unreadable Calibration Marks

Discard Glassware with Illegible Calibrations in GMP Laboratories

Remember: Laboratory glassware with unreadable volume markings must not be used—accurate measurements are essential for GMP analytical reliability.

Why This Matters in GMP

Accurate analytical testing relies heavily on the precision of volumetric instruments such as beakers, pipettes, and flasks. If calibration marks are faded, scratched, or illegible, the reliability of measurements is compromised, resulting in erroneous data. This can lead to out-of-specification (OOS) results, misinterpretation of batch quality, or regulatory non-compliance. GMP mandates the use of validated and calibrated instruments for all quality control operations. Damaged or degraded glassware should be discarded and replaced to maintain test precision and laboratory integrity.

Also Read: GMP Guidelines for Drug Formulation Development in Clinical Trials

Regulatory and Compliance Implications

FDA 21 CFR Part 211.160 and 211.68 require the use of accurate measuring devices and proper calibration practices. WHO GMP and Schedule M emphasize the use of clean, calibrated equipment with readable graduations. EU GMP Chapter 6 mandates documented procedures for qualification, calibration, and usage of laboratory instruments. Auditors review laboratory glassware during inspections, and unreadable equipment may lead to observations under data integrity or testing reliability violations.

Implementation Best Practices

Visually inspect all laboratory glassware periodically for calibration readability and

damage.

Maintain an equipment control list that includes condition checks of volumetric instruments.

Label defective glassware as “Do Not Use” and remove from testing areas immediately.

Procure Class A or certified volumetric glassware and document certificates of conformity.

Train QC personnel on glassware inspection criteria and handling practices.

Regulatory References

FDA 21 CFR Part 211.160 – Laboratory Controls
FDA 21 CFR Part 211.68 – Equipment Calibration
EU GMP Chapter 6 – Quality Control
WHO GMP – Laboratory Equipment Guidelines
Schedule M – Laboratory Instrument Maintenance