Standard Operating Procedure for Calibration of Viscometers for Cream Testing
| Department | Creams |
|---|---|
| SOP No. | SOP/CRM/160/2025 |
| Supersedes | SOP/CRM/160/2022 |
| Page No. | Page 1 of 5 |
| Issue Date | 21/01/2026 |
| Effective Date | 26/01/2026 |
| Review Date | 21/01/2027 |
1. Purpose
The purpose of this SOP is to define the procedure for calibrating viscometers used for testing the viscosity of cream products. Proper calibration ensures that viscosity measurements are accurate and reliable, meeting the required product specifications and regulatory standards.
2. Scope
This SOP applies to all viscometers used in the QC laboratory for testing cream formulations. It includes the procedure for calibrating both manual and automated viscometers to ensure accurate viscosity measurements.
3. Responsibilities
- Quality Control (QC) Team: Responsible for performing the calibration of viscometers, ensuring that they are within the required calibration standards, and maintaining accurate calibration records.
- Maintenance Team: Responsible for ensuring that the viscometers are in proper working condition and providing support for calibration and troubleshooting any equipment malfunctions.
- Laboratory Supervisor: Responsible for overseeing the calibration process and ensuring compliance with the SOP.
4. Accountability
The QC Manager is accountable for ensuring that viscometers are calibrated regularly and maintained in proper working condition.
The Laboratory Supervisor is responsible for supervising the calibration process and ensuring that it is completed as required. The Maintenance Team is responsible for repairing or servicing the equipment as necessary.
5. Procedure
5.1 Pre-Calibration Preparation
- Ensure that the viscometer is clean and free of any residue or contamination from previous tests.
- Verify that all necessary calibration standards and reference materials are available and within their expiration dates.
- Ensure that the viscometer is set up in a clean, controlled environment, free from vibration, temperature fluctuations, or any other factors that could affect its performance.
- Check the equipment for proper functioning and ensure that any issues such as malfunctions or wear and tear are addressed before calibration.
5.2 Calibration Procedure
- Select the appropriate calibration standards based on the viscosity range expected for the cream formulations being tested.
- For manual viscometers, fill the sample container with the calibration fluid or standard and attach it to the viscometer. For automated viscometers, ensure that the standard fluid is loaded into the instrument according to the manufacturer’s instructions.
- Perform the calibration according to the manufacturer’s guidelines, ensuring that the instrument is measuring viscosity correctly. The procedure typically involves comparing the readings from the viscometer with the known values of the calibration fluid.
- Record the readings from the viscometer and compare them with the expected values for the standard fluid. Any deviation from the expected values must be within the acceptable range specified by the manufacturer or regulatory standards.
5.3 Post-Calibration Checks
- If the calibration results are within the acceptable range, the viscometer is considered calibrated and ready for use.
- If the calibration results are outside the acceptable range, recalibrate the instrument using a different calibration fluid or check for any issues with the equipment (e.g., malfunctioning parts, improper setup).
- Record the calibration results, including the date, calibration fluid used, calibration values, and any corrective actions taken, in the Calibration Log (Annexure-1).
- If any corrective actions are needed, perform them and repeat the calibration process to ensure the instrument meets the required specifications.
5.4 Equipment Maintenance
- Ensure that the viscometer is properly maintained following the manufacturer’s maintenance schedule. Regular maintenance will ensure that the instrument continues to perform accurately and consistently.
- Schedule regular preventive maintenance and calibration checks as part of a routine maintenance program.
- Ensure that any malfunctioning equipment is repaired promptly, and calibration records are updated accordingly.
5.5 Documentation and Record-Keeping
- Document all calibration results, including any deviations, in the Calibration Log (Annexure-1). This includes both successful and unsuccessful calibration attempts.
- Ensure that all calibration records are signed off by the person performing the calibration and reviewed by the Laboratory Supervisor.
- Maintain calibration records for a minimum of two years or as required by regulatory guidelines.
- Ensure that all records are securely stored and readily available for review during internal audits or regulatory inspections.
6. Abbreviations
- GMP: Good Manufacturing Practices
- QC: Quality Control
- QA: Quality Assurance
- PPE: Personal Protective Equipment
7. Documents
- Annexure-1: Calibration Log
8. References
- Good Manufacturing Practices (GMP) Guidelines – 21 CFR Part 211
- International Conference on Harmonisation (ICH) Q7 – Good Manufacturing Practice for Active Pharmaceutical Ingredients
- Viscometer Manufacturer’s Calibration Guidelines
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Calibration Log
| Viscometer ID | Calibration Date | Calibration Fluid | Measured Viscosity | Expected Viscosity | Deviation | Operator |
|---|---|---|---|---|---|---|
| VM-001 | 21/01/2026 | Standard Fluid A | 85 cP | 80 cP | 5 cP | John Doe |
Revision History:
| Revision Date | Revision No. | Revision Details | Reason for Revision | Approved By |
|---|---|---|---|---|
| 01/03/2024 | 1.0 | Initial Version | New SOP Creation | QA Head |
| 01/03/2025 | 2.0 | Format Revision and Updates | Standardization of Document | QA Head |