Standard Operating Procedure for Monitoring CO₂ Levels in Incubators in Biosimilar Labs

Department	Biosimilars
SOP No.	SOP/BS/045/2025
Supersedes	SOP/BS/045/2022
Page No.	Page 1 of 10
Issue Date	04/05/2025
Effective Date	06/05/2025
Review Date	04/05/2026

1. Purpose

To outline the routine procedure for monitoring and verifying carbon dioxide (CO₂) concentrations in cell culture incubators used in biosimilar development, ensuring optimal atmospheric conditions for cell growth and viability.

2. Scope

This SOP applies to all CO₂ incubators used in biosimilar R&D laboratories and cell line development areas where mammalian cells are cultured for biosimilar product development.

3. Responsibilities

• Lab Technician: Conducts routine monitoring and records readings.
• Engineering/Maintenance Staff: Performs calibration and adjustment of CO₂ sensors if deviations are detected.
• QA Personnel: Reviews CO₂ monitoring records and verifies compliance.

4. Accountability

The Head of Biosimilar Manufacturing is accountable for ensuring the accuracy of CO₂ levels in all incubators used for critical cell culture operations.

5. Procedure

5.1 Monitoring Frequency and Instruments

1. Monitor CO₂ levels in each incubator:
   • Daily visual check of digital CO₂ display
   • Weekly verification using a calibrated external CO₂ analyzer
2. Ensure external analyzer is traceable and within calibration validity.

5.2 Daily Monitoring

1. Record displayed CO₂ percentage in the Incubator CO₂ Log (Annexure-1).
2. Expected range: 5.0% ± 0.2%
3. If out of range, inform Engineering immediately and initiate deviation form.

5.3 Weekly Verification Using External Analyzer

1. Place analyzer probe inside the incubator’s sample port or chamber.
2. Allow reading to stabilize for 3–5 minutes.
3. Record external analyzer reading and compare with incubator display.
4. If deviation exceeds ±0.2%, initiate CO₂ calibration.

5.4 CO₂ Level Adjustment

1. Adjust incubator CO₂ setpoint through the control panel following manufacturer’s guidelines.
2. Re-verify after 15 minutes to confirm stabilization.
3. Document adjustment in the CO₂ Correction Log (Annexure-2).

5.5 Gas Cylinder Management

1. Ensure CO₂ gas cylinders are replaced before depletion (<20%).
2. Record gas change in the CO₂ Gas Supply Log (Annexure-3).

5.6 Troubleshooting and Deviation Management

1. Common issues:
   • Blocked gas inlet
   • Sensor drift or fault
   • Leak in CO₂ tubing
2. Raise deviation report for any unresolved discrepancies and isolate incubator if required.

6. Abbreviations

• CO₂: Carbon Dioxide
• OOT: Out of Tolerance
• QA: Quality Assurance

7. Documents

1. Incubator CO₂ Log (Annexure-1)
2. CO₂ Correction Log (Annexure-2)
3. CO₂ Gas Supply Log (Annexure-3)

8. References

• WHO TRS 1010 – GMP Equipment Guidelines
• Manufacturer Manual for CO₂ Incubator (Model Specific)
• ICH Q9 – Quality Risk Management

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Incubator CO₂ Log

Date	Incubator ID	CO₂ Display (%)	Remarks	Initials
04/05/2025	INC-CO2-01	5.1	Within limit	AV

Annexure-2: CO₂ Correction Log

Date	Incubator ID	Observed Value (%)	Corrected To (%)	Adjusted By
03/05/2025	INC-CO2-02	4.7	5.0	Vinay Pawar

Annexure-3: CO₂ Gas Supply Log

Date	Cylinder ID	Replaced By	Remaining Pressure	Remarks
02/05/2025	CO2-2025-17	Sunita Reddy	18%	New cylinder installed

Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By
04/05/2025	2.0	Included weekly analyzer verification and cylinder tracking	Enhanced Monitoring