Standard Operating Procedure for Monitoring Spray Rate in Coating Machines
| Department | Tablet |
|---|---|
| SOP No. | SOP/TAB/140/2025 |
| Supersedes | SOP/TAB/140/2022 |
| 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 monitoring the spray rate in coating machines during tablet coating, ensuring uniform and controlled application of the coating material to the tablets.
2. Scope
This SOP applies to the monitoring of spray rate in the coating process for tablets, ensuring that the coating is applied consistently and meets the required specifications for tablet quality.
3. Responsibilities
- Quality Control (QC): Responsible for monitoring and recording the spray rate during the coating process to ensure it meets the specifications.
- Coating Operator: Responsible for adjusting and maintaining the spray rate on the coating machine, as per the defined parameters, during the coating process.
- Quality Assurance (QA): Ensures compliance with the SOP, reviews spray rate data, and verifies that the coating process remains within the required specifications.
4. Accountability
The QC Manager is accountable for ensuring that the spray rate is monitored and controlled during the coating process. The QA Manager is responsible for reviewing
the spray rate records and ensuring compliance with quality standards.
5. Procedure
5.1 Spray Rate Settings
- Before starting the coating process, ensure that the spray rate is set correctly according to the formulation specifications. The spray rate should be based on factors such as tablet size, coating material, and desired coating thickness.
- Set the spray rate on the coating machine, using the manufacturer’s guidelines for the equipment. Common spray rates are between 20-100 mL/min, depending on the tablet size and formulation.
- Ensure that the coating machine is calibrated to provide a consistent spray rate throughout the coating process. Verify that the spray nozzles are clean and functional before starting the process.
5.2 Monitoring Spray Rate During Coating
- During the coating process, continuously monitor the spray rate to ensure it remains consistent and within the specified range. Use a flow meter or other appropriate device to measure the spray rate at regular intervals.
- Check the spray rate at predefined intervals, such as every 30 minutes or after every 100 kg of coated tablets, depending on the batch size.
- If the spray rate deviates from the specified range, pause the coating process and adjust the settings on the coating machine.
5.3 Adjustments and Corrective Actions
- If the spray rate is found to be outside the acceptable range, make the necessary adjustments to the coating machine settings. Common adjustments include modifying the air pressure, pump speed, or nozzle size.
- If the spray rate is too high, reduce the flow rate to prevent over-coating and ensure an even coating layer.
- If the spray rate is too low, increase the flow rate to ensure sufficient coverage of the tablets with the coating material.
- Once adjustments are made, recheck the spray rate to confirm it is within the acceptable range before resuming the coating process.
5.4 Documentation
- Document the spray rate settings, monitoring results, and any adjustments made during the coating process in the batch record (Annexure-2).
- Record the spray rate at each monitoring interval and document any deviations from the specified range, along with corrective actions taken, in the deviation report (Annexure-1).
- Ensure that all records are signed, dated, and reviewed by QA for compliance with quality standards.
5.5 Acceptance Criteria
- The spray rate should remain within the specified range throughout the coating process. Common specifications are typically between 20-100 mL/min, but these may vary depending on the product requirements.
- If the spray rate deviates outside of the acceptable range, corrective actions should be taken, and the batch may need to be stopped for reprocessing.
5.6 Post-Coating Actions
- Once the coating process is complete and the spray rate has been confirmed to be within specification, proceed with the next stages of tablet processing, including drying, packaging, and labeling.
- Ensure that the coating machine is cleaned, calibrated, and maintained according to the preventive maintenance schedule after each use.
6. Abbreviations
- SOP: Standard Operating Procedure
- GMP: Good Manufacturing Practice
- QC: Quality Control
- QA: Quality Assurance
7. Documents
- Batch Record (Annexure-2)
- Deviation Report (Annexure-1)
8. References
- USP <701> – Coating Process for Tablets
- 21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals (US FDA)
- European Pharmacopoeia (EP) – Coating Specifications for Tablets
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 | Spray rate exceeded specified range | Adjusted spray nozzle pressure and re-tested | John Doe |
Annexure-2: Batch Record
| Sample Number | Spray Rate | Deviation | Action Taken |
|---|---|---|---|
| Sample 1 | 50 mL/min | Pass (Deviation: 2%) | 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 | Updated spray rate monitoring process | Improved process monitoring | QA Head |