Standard Operating Procedure for Weighing of Raw Materials Under LAF in API Manufacturing

Department	API Manufacturing
SOP No.	SOP/API/015/2025
Supersedes	SOP/API/015/2022
Page No.	Page 1 of 10
Issue Date	13/04/2025
Effective Date	15/04/2025
Review Date	13/04/2026

1. Purpose

To define the procedure for weighing raw materials under Laminar Air Flow (LAF) to maintain accuracy, prevent cross-contamination, and ensure environmental control in accordance with GMP principles.

2. Scope

This SOP applies to the weighing of all raw materials used in API manufacturing that require controlled environmental conditions to ensure product quality and operator safety.

3. Responsibilities

• Warehouse Operator: Conduct weighing under LAF, maintain cleanliness, and record weights accurately.
• QA Officer: Verify LAF conditions and check for adherence to weighing procedure.
• Engineering Team: Maintain and calibrate LAF units and balances as per schedule.

4. Accountability

The Warehouse Manager is accountable for ensuring that weighing operations under LAF are performed correctly, recorded, and that equipment is validated and maintained.

5. Procedure

5.1 Pre-Weighing Checks

1. Ensure the LAF unit is operational and cleaned as per its respective SOP.
2. Switch ON the LAF and allow for a minimum of 15 minutes of air flow before initiating weighing.
3. Verify that the area is clean and that cleaning status label is in place.
4. Check the calibration status of the balance — calibration date must be current.
5. Check raw material label for:
   • Name
   • Batch No.
   • Status (Approved)
   • Expiry Date

5.2 Weighing Procedure

1. Wear appropriate PPE including gloves, mask, and clean room gown.
2. Place a clean, pre-labeled container or liner on the balance.
3. Tare the balance to zero.
4. Using a clean scoop, slowly transfer the required quantity of material to the container.
5. Ensure minimal dusting and avoid spilling by transferring at low height.
6. Record the net weight and verify it against the material requisition.
7. Once complete, close the container securely and affix “WEIGHED” label with:
   • Material Name
   • Batch No.
   • Weighed Quantity
   • Weighed By
   • Date & Time

5.3 Post-Weighing Activities

1. Clean the balance and working surface with 70% IPA.
2. Switch OFF the LAF after allowing for a 10-minute post-operation air flush.
3. Return the excess material (if applicable) back to the original container and label as “PARTIAL.”
4. Log the weighed material in the “Weighing Logbook” (Annexure-1).
5. QA to cross-check the label and quantity before transferring material to the production staging area.

6. Abbreviations

• SOP: Standard Operating Procedure
• LAF: Laminar Air Flow
• IPA: Isopropyl Alcohol
• QA: Quality Assurance

7. Documents

1. Weighing Logbook (Annexure-1)
2. Balance Calibration Record (Annexure-2)
3. LAF Cleaning Record (Annexure-3)

8. References

• ICH Q7 – GMP Guidelines for Active Pharmaceutical Ingredients
• 21 CFR Part 211.68 – Automatic, mechanical, and electronic equipment
• WHO TRS 961 Annex 9 – Guidance on Good Storage Practice

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Weighing Logbook

Date	Material	Batch No.	Weighed Qty	Weighed By	Verified By
13/04/2025	API-123	AP202504	15 kg

Annexure-2: Balance Calibration Record

Date	Balance ID	Calibrated By	Next Due	Status
01/04/2025	BL-101		01/10/2025	Calibrated

Annexure-3: LAF Cleaning Record

Date	LAF ID	Cleaned By	Verified By	Remarks
12/04/2025	LAF-02			Cleaned & operational

Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By
01/01/2022	1.0	Initial Issue	GMP Compliance	QA Head
13/04/2025	2.0	Added Post-Weighing Disinfection Step	Audit Finding	QA Head