Standard Operating Procedure for In-Process Particle Size Distribution Testing

Department	Tablet
SOP No.	SOP/TAB/146/2025
Supersedes	SOP/TAB/146/2022
Page No.	Page 1 of 6
Issue Date	01/03/2026
Effective Date	06/03/2026
Review Date	01/03/2027

1. Purpose

To define the procedure for testing the particle size distribution of granules or powders during the tablet manufacturing process to ensure the product meets the required quality standards for uniformity and performance.

2. Scope

This SOP applies to the in-process monitoring of particle size distribution during tablet granulation, blending, and final tablet formation to ensure consistent tablet quality and dissolution properties.

3. Responsibilities

• Quality Control (QC): Responsible for conducting the particle size distribution tests on granules or powders during various stages of tablet production.
• Production Operator: Responsible for sampling the material at specified intervals and ensuring the sample is representative for testing.
• Quality Assurance (QA): Ensures compliance with this SOP and reviews particle size distribution data to confirm that it meets specifications.

4. Accountability

The QC Manager is accountable for ensuring that particle size distribution tests are performed at appropriate stages of tablet production. The QA Manager ensures that the process is followed, and that the results are reviewed and approved in accordance with quality standards.

5. Procedure

5.1 Sampling

1. During granulation and blending stages, collect samples of granules or powders at defined intervals (e.g., every 100 kg or after each batch of granulation).
2. Ensure the sample is representative of the entire batch and is collected following the sampling procedure outlined in the relevant SOP.

5.2 Preparing Testing Equipment

1. Ensure the particle size analyzer or sieve shaker is clean and calibrated according to the manufacturer’s instructions and internal calibration procedures.
2. Prepare the equipment and set it up to match the type of material being tested (e.g., dry sieving, laser diffraction).

5.3 Performing Particle Size Distribution Testing

1. Weigh a sufficient amount of the sample to meet the requirements of the particle size testing method (typically 10-50 grams depending on the material).
2. Test the sample using the appropriate method (e.g., laser diffraction, sieve analysis). Follow the method’s specific instructions regarding time and procedure.
3. Record the particle size distribution results, including the d50, d90, and any other relevant parameters as specified in the product specifications.

5.4 Documentation and Records

1. Document the particle size distribution data in the batch record (Annexure-2), including the sample number, test method, and results.
2. If any deviations are observed from the acceptable particle size distribution range, generate a deviation report (Annexure-1) and initiate an investigation into the cause of the deviation.

5.5 Acceptance Criteria

1. The particle size distribution of the granules or powders must fall within the predefined specifications to ensure consistent tablet performance, including dissolution rate and tablet uniformity.
2. If the results fall outside the specified range, corrective actions must be taken, and the batch may need to be rejected or reprocessed.

5.6 Post-Testing Actions

1. If the particle size distribution meets the specifications, proceed with the next stages of tablet production, such as compression or coating.
2. If the particle size is out of specification, review the process, investigate the root cause, and take corrective actions such as rework or formulation adjustments.

6. Abbreviations

• SOP: Standard Operating Procedure
• GMP: Good Manufacturing Practice
• QC: Quality Control
• QA: Quality Assurance
• d50: Median particle size
• d90: Particle size at 90% cumulative distribution

7. Documents

1. Batch Record (Annexure-2)
2. Deviation Report (Annexure-1)

8. References

• USP <701> – Granulation and Particle Size Testing
• 21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals (US FDA)
• European Pharmacopoeia (EP) – Particle Size Distribution Specifications

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Deviation Report

Deviation Date	Batch Number	Deviation Description	Corrective Action	Responsible Person
15/12/2025	Batch 001	Particle size exceeded acceptable range	Reprocessed batch and adjusted granulation process	John Doe

Annexure-2: Batch Record

Sample Number	Particle Size Distribution	Action Taken
Sample 1	90% < 200 μm	Accepted

Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By
01/01/2024	1.0	Initial Version	New SOP Creation	QA Head
01/02/2025	2.0	Added in-process testing requirements	Process improvement	QA Head