Procedure for Ensuring Accuracy in Weighing Raw Materials

Department	Production/Quality Assurance (QA)/Quality Control (QC)/Warehouse
SOP No.	SOP/Ointment/173
Supersedes	V 1.0
Page No.	Page X of Y
Issue Date	[Insert Issue Date]
Effective Date	[Insert Effective Date]
Review Date	[Insert Review Date]

1. Purpose

The purpose of this Standard Operating Procedure (SOP) is to define a systematic approach for ensuring accuracy in weighing raw materials during pharmaceutical manufacturing. Accurate weighing is critical to maintaining product quality, batch consistency, and compliance with Good Manufacturing Practices (GMP) and regulatory guidelines.

2. Scope

This SOP applies to all personnel in the Production, Quality Assurance (QA), Quality Control (QC), and Warehouse departments responsible for the receipt, storage, and weighing of raw materials in pharmaceutical manufacturing.

3. Responsibilities

• Weighing Operator: Performs accurate weighing of raw materials following GMP protocols.
• QA Officer: Ensures proper documentation and compliance with standard limits.
• QC Analyst: Verifies raw material identity, quality, and weight accuracy.
• Warehouse Supervisor: Ensures proper storage and handling of raw materials before weighing.
• Production Supervisor: Oversees the entire weighing operation and ensures adherence to procedures.

4. Accountability

The QA Manager is accountable for ensuring that all weighing activities comply with GMP, FDA, ICH, WHO, and company policies.

5. Procedure

5.1 Preparation for Weighing

• Verify the cleanliness of the weighing area and balance.
• Ensure that the balance calibration status is **current and valid**.
• Confirm that the weighing room is under controlled environmental conditions:
  • Temperature: **15-25°C**
  • Humidity: **30-50% RH**
• Check the raw material label for:
  • Material name
  • Batch number
  • Manufacturing and expiry date
  • Storage conditions
• Ensure that personal protective equipment (PPE) is worn, including:
  • Gloves
  • Hairnets
  • Goggles
  • Protective gowns

5.2 Weighing Process

• Place a **”Weighing in Progress”** sign outside the weighing area.
• Use **pre-verified and calibrated** weighing balances.
• Before weighing, ensure that the balance is **tared correctly**.
• Place the **correct weighing container** on the balance.
• Weigh the raw material as per the batch manufacturing record (BMR) requirements.
• Record the weight in the **Raw Material Weighing Log (Annexure-1).**

5.3 Handling Weighing Deviations

• If the weight exceeds the tolerance range, **stop weighing and inform QA immediately.**
• Incorrectly weighed material must be:
  • Reweighed with supervision.
  • Returned to storage if within acceptance limits.
  • Disposed of if rejected, following waste disposal guidelines.
• All weighing deviations must be documented in the **Weighing Deviation Log (Annexure-2).**

5.4 Post-Weighing Activities

• Securely seal and label all weighed materials.
• Ensure proper documentation of all weights.
• Clean the balance and surrounding areas to remove any residual material.
• Submit the completed weighing log to the **QA department for review.**

5.5 Equipment Calibration and Maintenance

• Weighing balances must be calibrated **daily before use.**
• QA must perform **weekly verification** of calibration records.
• Any defective balance must be **tagged as “Out of Service”** and reported to maintenance.

6. Abbreviations

• GMP – Good Manufacturing Practices
• QA – Quality Assurance
• QC – Quality Control
• FDA – Food and Drug Administration
• ICH – International Council for Harmonisation
• BMR – Batch Manufacturing Record

7. Documents

• Raw Material Weighing Log (Annexure-1)
• Weighing Deviation Log (Annexure-2)

8. References

• ICH Q7 – GMP for Active Pharmaceutical Ingredients
• WHO Guidelines on Good Weighing Practices
• FDA Guidance on Pharmaceutical Manufacturing

9. SOP Version

Version 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Raw Material Weighing Log

Date	Material Name	Batch No.	Required Weight	Actual Weight	Operator	QA Review
02/02/2025	API X	SOP/Ointment/1001	5.0 kg	5.01 kg	John Doe	Approved

Annexure-2: Weighing Deviation Log

Date	Material Name	Batch No.	Deviation Type	Root Cause	Corrective Action	QA Approval
02/02/2025	API X	SOP/Ointment/1001	Overweight	Operator Error	Reweighed	Approved

12. Revision History

Revision Date	Revision No.	Details	Reason	Approved By
02/02/2025	2.0	Expanded Weighing Accuracy Procedures	Improved GMP Compliance	QA Head