Standard Operating Procedure for Using pH Meter

1) Purpose

The purpose of this SOP is to outline the procedure for the proper operation and maintenance of the pH meter used in the manufacturing of otic dosage forms to ensure accurate and consistent pH measurements.

2) Scope

This SOP applies to all personnel involved in the operation and maintenance of the pH meter in the pharmaceutical manufacturing facility.

3) Responsibilities

Operators: Responsible for correctly using the pH meter as per this SOP.
Quality Control (QC) Personnel: Responsible for calibration and verification of the pH meter.
Maintenance Personnel: Responsible for the upkeep and repair of the pH meter.

4) Procedure

4.1 Operation
4.1.1 Preparation
4.1.1.1 Ensure the pH meter is on a stable, level surface.
4.1.1.2 Rinse the pH electrode with distilled water before use.
4.1.1.3 Check that the pH meter is properly calibrated.

4.1.2 pH Measurement Procedure
4.1.2.1 Turn on the pH meter and allow it to stabilize.
4.1.2.2 Prepare the sample solution to be tested.
4.1.2.3 Immerse the pH electrode into the sample solution.
4.1.2.4 Stir the solution gently and allow the reading to stabilize.
4.1.2.5 Record the pH value displayed on the meter.

4.2 Calibration
4.2.1 Daily Calibration
4.2.1.1 Perform a daily calibration using standard buffer solutions (pH 4.0, 7.0, and 10.0) before taking measurements.
4.2.1.2 Record the calibration results in the calibration log.

4.2.2 Monthly Calibration
4.2.2.1 Conduct a full calibration of the pH meter monthly using certified buffer solutions.
4.2.2.2 Document the calibration results and any necessary adjustments.

4.3 Maintenance
4.3.1 Routine Maintenance
4.3.1.1 Clean the pH electrode regularly to prevent contamination.
4.3.1.2 Store the pH electrode in a storage solution when not in use.

4.3.2 Troubleshooting
4.3.2.1 If the pH meter displays error messages or unstable readings, refer to the manufacturer’s manual for troubleshooting steps.
4.3.2.2 Contact maintenance personnel if issues persist.

5) Abbreviations, if any

QC: Quality Control
SOP: Standard Operating Procedure

6) Documents, if any

Calibration log
Maintenance log

7) Reference, if any

Manufacturer’s manual for the pH meter
Regulatory guidelines for equipment calibration and maintenance

8) SOP Version

Version 1.0