Responsibilities

• Production Chemist: Ensure correct placement and usage of thermocouples during batch processes.
• Engineering Department: Calibrate and maintain thermocouples according to schedule.
• QA Officer: Verify thermocouple calibration and compliance with GMP documentation requirements.

4. Accountability

The Engineering Head is accountable for maintenance and calibration. The Production Head is accountable for operational use, and the QA Head is responsible for ensuring regulatory compliance.

5. Procedure

5.1 Types of Thermocouples

1. Use Type K (Nickel-Chromium/Nickel-Alumel) or Type J thermocouples for general purpose temperature monitoring unless otherwise specified.
2. Thermocouples must be selected based on:
   • Process temperature range
   • Chemical compatibility
   • Length and diameter suitable for reactor size

5.2 Pre-Use Inspection

1. Verify calibration label and due date before each use.
2. Ensure insulation sheath is intact, wire tips are clean, and no physical damage is observed.
3. Check for proper sensor response using hot water or calibration source (if applicable).

5.3 Installation and Placement

1. Insert the thermocouple through the designated port of the vessel/reactor/dryer.
2. Ensure the tip reaches the center/mass of the material for accurate readings.
3. Secure the thermocouple with clamps or fittings to avoid movement or displacement.
4. Connect the thermocouple to a calibrated temperature indicator or digital data logger.

5.4 During Operation

1. Monitor temperature at defined intervals as per BMR.
2. Record readings manually or ensure automated data capture is functioning.
3. Ensure that temperature alarms or control loops using thermocouple inputs are functional.

5.5 Post-Use Care

1. Carefully remove thermocouple from equipment after process completion.
2. Clean the thermocouple with 70% IPA or suitable solvent, ensuring no residues are left on the sheath.
3. Inspect for damage. If damaged, label as “Out of Use” and inform Engineering for replacement.

5.6 Calibration and Maintenance

1. Thermocouples shall be calibrated annually or as per the calibration SOP.
2. Calibration shall be traceable to national/international standards and documented in the Calibration Record (Annexure-2).
3. Calibration status shall be indicated by a visible label with due date, serial number, and calibrated by information.

5.7 Documentation

1. Record the following in the Thermocouple Usage Log (Annexure-1):
   • Thermocouple ID
   • Date of use
   • Batch number
   • Equipment name
   • Process stage
   • Initial and final readings

6. Abbreviations

• SOP: Standard Operating Procedure
• API: Active Pharmaceutical Ingredient
• QA: Quality Assurance
• BMR: Batch Manufacturing Record

7. Documents

1. Thermocouple Usage Log (Annexure-1)
2. Thermocouple Calibration Record (Annexure-2)

8. References

• ICH Q7 – GMP Guidelines for APIs
• 21 CFR Part 211 – cGMP for Finished Pharmaceuticals
• USP <1058> – Analytical Instrument Qualification

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Thermocouple Usage Log

Date	Thermocouple ID	Batch No.	Equipment	Stage	Initial Temp (°C)	Final Temp (°C)	Checked By
13/04/2025	TC-09	API-20250413	Reactor R1	Crystallization	24.5	15.2

Annexure-2: Thermocouple Calibration Record

Thermocouple ID	Calibrated On	Calibrated By	Due Date	Remarks
TC-09	01/04/2025	Maintenance Engineer	01/04/2026	Pass

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
01/01/2022	1.0	Initial Issue	New SOP	QA Head
13/04/2025	2.0	Added usage log, clarified calibration process	GMP Compliance	QA Head