Standard Operating Procedure for Headspace Oxygen Level Control in Elixir Manufacturing
| Department | Elixir Department |
|---|---|
| SOP No. | SOP/ELX/108/2025 |
| Supersedes | SOP/ELX/108/2022 |
| Page No. | Page 1 of 8 |
| Issue Date | 11/04/2025 |
| Effective Date | 15/04/2025 |
| Review Date | 11/04/2026 |
1. Purpose
To define the procedure for controlling and monitoring the oxygen level in the headspace of mixing and storage tanks used in elixir manufacturing, in order to prevent oxidative degradation of sensitive ingredients.
2. Scope
This SOP applies to all tanks used for processing, holding, or transferring oxygen-sensitive elixirs in the Elixir Department, including nitrogen purging or inert gas blanketing systems.
3. Responsibilities
- Production Operator:
- Perform and document headspace oxygen level control activities.
- Production Supervisor:
- Review oxygen readings and ensure corrective actions where required.
- QA Officer:
- Verify compliance with specified oxygen limits and sign off before batch release.
4. Accountability
The Head of Production is accountable for ensuring proper control of oxygen in the tank headspace and documentation of monitoring activities.
5. Procedure
5.1 Applicable Batches
- Refer to the Master Formula Record (MFR)
to identify if the product requires oxygen control.
Note the acceptable headspace oxygen level defined (typically below 2.0%).
5.2 Equipment Preparation
- Ensure oxygen analyzer is calibrated and labeled “CALIBRATED.”
- Use only cleaned and validated sampling ports for measurement.
- Connect nitrogen (or other inert gas) to the tank inlet port using sterile filters (0.2 µm).
5.3 Oxygen Level Monitoring Procedure
- Take initial oxygen reading in the headspace before purging using a handheld or inline oxygen analyzer.
- If oxygen level is above the permissible limit, initiate nitrogen purging.
- Open the vent slightly to allow displacement of oxygen with nitrogen.
- Continue purging until oxygen level is below the target (e.g., 2.0%).
- Record final oxygen level and time taken in the Oxygen Monitoring Log (Annexure-1).
5.4 Post-Purging Controls
- Close inlet and outlet valves tightly to maintain inert environment.
- Affix label “OXYGEN CONTROLLED” on the tank and mention date/time.
- Repeat oxygen level check after 2 hours to ensure stability (if batch is held longer).
5.5 Corrective Action
- If oxygen level exceeds the limit after storage, repeat nitrogen purging.
- Investigate for leaks or faulty gaskets and document deviation if applicable.
6. Abbreviations
- SOP: Standard Operating Procedure
- QA: Quality Assurance
- MFR: Master Formula Record
7. Documents
- Oxygen Monitoring Log (Annexure-1)
- Batch Manufacturing Record (BMR)
- Calibration Logbook for Oxygen Analyzer
8. References
- WHO TRS 1010 – GMP Guidelines
- ICH Q1A(R2) – Stability Testing of New Drug Substances and Products
- 21 CFR Part 211.113 – Control of Microbial Contamination
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Oxygen Monitoring Log
| Date | Batch No. | Tank No. | Initial O2 Level (%) | Final O2 Level (%) | Purge Duration (min) | Operator | QA Verified |
|---|---|---|---|---|---|---|---|
| 11/04/2025 | ELX-1045 | TANK-04 | 5.6% | 1.8% | 12 | Rajesh Kumar | Sunita Reddy |
Revision History:
| Revision Date | Revision No. | Revision Details | Reason for Revision | Approved By |
|---|---|---|---|---|
| 01/01/2024 | 1.0 | Initial SOP Release | New SOP | QA Head |
| 11/04/2025 | 2.0 | Updated oxygen control steps and log format | Stability Enhancement | QA Head |