Standard Operating Procedure for Calibration of Incubators for Cell Growth in Biosimilar R&D

Department	Biosimilars
SOP No.	SOP/BS/044/2025
Supersedes	SOP/BS/044/2022
Page No.	Page 1 of 11
Issue Date	04/05/2025
Effective Date	06/05/2025
Review Date	04/05/2026

1. Purpose

To define the procedure for the periodic calibration of incubators used in biosimilar R&D for maintaining required environmental conditions (temperature and CO₂ concentration) to support viable and reproducible cell growth.

2. Scope

This SOP applies to all CO₂ incubators and humidity-controlled chambers used for the cultivation of mammalian cells in the biosimilar laboratory and cell line development areas.

3. Responsibilities

• Engineering/Maintenance Team: Performs calibration using certified instruments and logs results.
• QA Representative: Reviews and verifies calibration data and certificates.
• Lab Users: Report deviations and support calibration activities by making incubators available.

4. Accountability

The Head of Engineering is accountable for ensuring that all incubators are calibrated as per schedule and perform within the validated range for accurate cell culture conditions.

5. Procedure

5.1 Calibration Frequency

1. Perform calibration of each incubator:
   • Quarterly (Temperature)
   • Half-yearly (CO₂ and humidity, if applicable)
2. Use traceable calibration instruments (e.g., calibrated thermometer, CO₂ gas analyzer).

5.2 Pre-Calibration Checklist

1. Switch incubator to standby mode.
2. Remove cell cultures, sensors, and trays.
3. Ensure the chamber is clean and dry.
4. Log equipment details in Calibration Record Log (Annexure-1).

5.3 Temperature Calibration

1. Place three-point temperature sensors inside the chamber (top, center, bottom shelves).
2. Set incubator to 37°C and record readings for 30 minutes at 5-minute intervals.
3. Acceptance Criteria: ±0.5°C from setpoint.
4. Document average readings and deviation calculations in Annexure-2.

5.4 CO₂ Calibration

1. Use calibrated CO₂ gas analyzer to measure chamber levels.
2. Inject 5% CO₂ and allow stabilization for 15 minutes.
3. Compare analyzer reading to incubator display.
4. Adjust sensor via manufacturer’s manual if deviation exceeds ±0.2%.

5.5 Post-Calibration Steps

1. Reinstall shelves and sensor probes.
2. Label incubator with calibration tag showing date, due date, and performed by.
3. Update Calibration Status Log (Annexure-3).

5.6 Out-of-Tolerance (OOT) Handling

1. If any parameter is out of tolerance:
   • Quarantine incubator from use.
   • Initiate deviation report and assess impact on cultures.
   • Perform root cause analysis and recalibrate after service.

6. Abbreviations

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

7. Documents

1. Calibration Record Log (Annexure-1)
2. Temperature Calibration Log (Annexure-2)
3. Calibration Status Log (Annexure-3)

8. References

• ICH Q7: GMP for Active Pharmaceutical Ingredients
• WHO TRS 1010 Annex 2 – Equipment Qualification
• Manufacturer Manuals for Incubators

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Calibration Record Log

Incubator ID	Make/Model	Location	Calibration Date	Next Due
INC-101	Thermo Forma 311	CLD Lab	03/05/2025	03/08/2025

Annexure-2: Temperature Calibration Log

Location	Target Temp (°C)	Observed Avg (°C)	Deviation	Status
Center Shelf	37.0	36.8	-0.2	Pass

Annexure-3: Calibration Status Log

Date	Incubator ID	Calibrated By	Tag Placed	Comments
03/05/2025	INC-101	Vinay Pawar	Yes	CO₂ sensor adjusted

Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By
04/05/2025	2.0	Inclusion of OOT handling and humidity reference	Calibration compliance enhancement