Procedure for Viscosity Testing of Liquids
1) Purpose
The purpose of this SOP is to outline the procedure for measuring the viscosity of liquid samples used in pharmaceutical manufacturing to ensure consistency and quality control.
2) Scope
This SOP applies to all liquid formulations produced within the manufacturing facility that require viscosity testing.
3) Responsibilities
Quality Control (QC) Department: Responsible for conducting viscosity measurements and ensuring compliance with this SOP.
Production Department: Responsible for providing liquid samples and maintaining process parameters.
4) Procedure
4.1 Equipment Preparation:
4.1.1 Calibrate the viscometer using standard viscosity calibration fluids as per the manufacturer’s instructions.
4.1.2 Ensure the viscometer is clean and free from any residues that could affect measurements.
4.1.3 Set the viscometer to the appropriate speed and spindle size based on the viscosity range of the sample.
4.2 Viscosity Measurement Procedure:
4.2.1 Place a sufficient amount of the liquid sample into the viscometer chamber.
4.2.2 Lower the spindle into the sample, ensuring it is fully immersed.
4.2.3 Start the viscometer and allow sufficient time for the reading to stabilize (typically 30 seconds to 1 minute).
4.2.4 Record the viscosity reading displayed on the viscometer screen.
4.2.5 Repeat the measurement at least three times for each sample to ensure consistency.
4.3 Calculation and Interpretation:
4.3.1 Calculate the average viscosity value from the multiple measurements.
4.3.2 Compare the measured viscosity with the specified limits or target viscosity range for the product.
4.3.3 Document any deviations from expected viscosity values and take appropriate corrective actions if necessary.
4.4 Acceptance Criteria:
4.4.1 The viscosity of the liquid sample meets the specified range or target value as per product requirements.
4.4.2 Viscometer calibration check is performed at regular intervals and meets acceptance criteria.
4.5 Documentation:
4.5.1 Record all viscosity measurements, calibration checks, and any corrective actions taken in the Viscosity Testing Record.
4.5.2 Review and approve the documentation by QC Manager.
5) Abbreviations, if any
QC: Quality Control
6) Documents, if any
Viscosity Testing Record
Calibration Record for Viscometer
Sampling Plan Document
7) Reference, if any
USP General Chapter <911> – Viscosity
21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals
8) SOP Version
Version 1.0