Standard Operating Procedure for Conducting Process Capability Studies for Gel Manufacturing
| SOP No. | SOP/GM/112/2025 |
|---|---|
| Version | 2.0 |
| Effective Date | 05/06/2025 |
| Review Date | 03/06/2026 |
| Supersedes | SOP/GM/112/2023 |
| Approval | QA Head |
| Prepared By | Production Department |
1. Purpose
To establish a standard procedure for conducting process capability studies to evaluate the consistency and predictability of gel manufacturing processes.
2. Scope
This SOP applies to all new and modified gel manufacturing processes that require validation of process capability prior to full-scale production.
3. Responsibilities
- Production Team: Execution of trial batches and data collection.
- Quality Assurance: Oversight, verification, and reporting.
- Quality Control: Analytical testing and data analysis support.
- Statistical Analyst/Process Engineer: Data modeling and capability calculations.
4. Accountability
Head – Manufacturing
5. Procedure
- Identification of Critical Parameters:
- Select critical process parameters (CPPs) and critical quality attributes (CQAs) such as pH, viscosity, fill weight, and homogeneity.
- Define acceptable limits
based on formulation requirements and prior process knowledge.
Sampling Strategy:
Data Collection:
Statistical Analysis:
Capability Index Interpretation:
Documentation and Reporting:
Follow-up Actions:
- Conduct at least 20-30 observations for each parameter from routine or pilot production batches.
- Use random sampling methods to avoid bias.
- Document each reading along with batch ID, operator, time, and machine used.
- Ensure use of calibrated instruments.
- Calculate mean (μ), standard deviation (σ), Cp, Cpk values for each parameter.
- Use control charts to identify trends and outliers.
- Assess normality using histograms and normal probability plots.
- Cp & Cpk ≥ 1.33: Process is capable.
- 1.0 ≤ Cp & Cpk < 1.33: Process may require improvement.
- Cp & Cpk < 1.0: Process is not capable – initiate root cause analysis.
- Compile data into a Process Capability Study Report.
- Highlight critical findings, trends, and recommendations.
- Review and approve report through QA and Manufacturing Head.
- Update process parameters, SOPs, and control limits as needed.
- Implement CAPA for any deficiencies identified during the study.
6. Abbreviations
- CPP – Critical Process Parameter
- CQA – Critical Quality Attribute
- Cp – Process Capability Index
- Cpk – Process Capability Performance Index
- SOP – Standard Operating Procedure
- CAPA – Corrective and Preventive Action
7. Documents
- Process Capability Study Protocol – Annexure 1
- Raw Data Log Sheet – Annexure 2
- Capability Analysis Report Template – Annexure 3
- Corrective Action Report Format – Annexure 4
8. References
- ICH Q9 – Quality Risk Management
- ISO 7870 – Control Charts
- Schedule M – Indian GMP Guidelines
9. SOP Version History
| Version | Effective Date | Reason for Revision |
|---|---|---|
| 1.0 | 15/03/2023 | Initial issue |
| 2.0 | 05/06/2025 | Enhanced statistical analysis and graphical tools added |
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | Jr. Production Chemist | QA Executive | Head – Manufacturing |
| Department | Gel Manufacturing | Quality Assurance | Manufacturing |
11. Annexures
| Annexure No. | Title | Description / Format |
|---|---|---|
| Annexure 1 | Process Capability Study Protocol | Outlines parameter selection, sampling plan, statistical approach. |
| Annexure 2 | Raw Data Log Sheet | Table format capturing each observation with timestamp, parameter, result. |
| Annexure 3 | Capability Analysis Report | Contains mean, Cp, Cpk, graphs, conclusion and recommendations. |
| Annexure 4 | Corrective Action Report | Form with deviation description, cause, corrective action and effectiveness check. |