SOP for Calibration of Infrared Moisture Balance | Step-by-Step Guide for QC Labs

Learn the complete SOP for Calibration of Infrared Moisture Balance to ensure accurate moisture measurements in quality control. Step-by-step procedure, tips, and FAQs included.

SOP for Calibration of Infrared Moisture Balance: A Complete Guide

Ensuring accurate and reliable moisture analysis is essential for any quality control (QC) lab. The SOP for Calibration of Infrared Moisture Balance provides a standardized procedure to calibrate the equipment by comparing it with the Loss on Drying (LOD) method at 105°C. Proper calibration ensures consistent results, compliance with regulatory standards, and improved product quality.

1. Objective

The purpose of this SOP is to calibrate the infrared moisture balance accurately to guarantee reliable results during moisture determination. Regular calibration prevents discrepancies and maintains the integrity of your QC measurements.

2. Scope

This procedure applies to all infrared moisture balances installed in the quality control department. It is relevant for both raw materials and in-process granules used in production.

3. Responsibility

• Performed by: Technical Assistant
• Checked by: Executive / Manager

4. Accountability

The Head of the Department is accountable for ensuring the SOP is followed and calibration records are maintained.

5. Procedure for Calibration

Frequency: Once every three months

Step-by-Step Guide:

1. Operate the infrared moisture balance as per its standard operating procedure.
2. Set the desired temperature using the voltage regulator knob.
3. Allow the instrument to stabilize for fifteen minutes, then observe and record the temperature in the calibration annexure.
4. Select a representative sample (e.g., starch or any in-process granules) and perform the LOD test at 105°C. Record the percentage of LOD in Annexure-I.
5. Using the same sample, perform the moisture analysis in the infrared moisture balance at the same temperature and record the results in the annexure.
6. Compare the % LOD obtained from the oven and the infrared balance. The instrument is considered satisfactorily calibrated if the difference is within 10% of the LOD observed in the oven. If not, follow the corrective action as per the SOP.

6. Abbreviations

• % – Percentage
• LOD – Loss on Drying
• I.R. – Infrared

7. Key Points to Remember

• Calibration should be performed consistently every three months.
• Always use a representative sample for accurate comparison.
• Maintain proper records in annexures for audit and compliance purposes.
• Ensure the equipment is in good working condition before calibration.

Frequently Asked Questions (FAQs)

1. What is the purpose of the SOP for Calibration of Infrared Moisture Balance?
The SOP ensures that the infrared moisture balance provides accurate and reliable moisture measurements by comparing it with the standard LOD method at 105°C.

2. How often should the infrared moisture balance be calibrated?
Calibration should be performed once every three months to maintain measurement accuracy.

3. What samples are used for calibration?
Representative samples such as starch or in-process granules are used to compare LOD values between the oven and the infrared moisture balance.

4. What is the acceptable tolerance for calibration?
The calibration is satisfactory if the difference between the oven LOD and the infrared moisture balance LOD is within 10%.

5. Who is responsible for performing and checking the calibration?
The Technical Assistant performs the calibration, while the Executive or Manager checks it. The Head of the Department is accountable for overall compliance.