Ensures that safety protocols are followed during the testing process, especially in relation to handling microbial cultures and testing materials.

Laboratory Personnel: Responsible for carrying out the microbial limit tests using appropriate techniques and equipment, and ensuring that the test conditions are controlled and documented.

4. Accountability

The Manufacturing Manager is accountable for ensuring that microbial limit tests are performed as part of the quality control process. The overall compliance with this SOP is overseen by the Quality Assurance (QA) Manager.

5. Procedure

5.1. Pre-Test Preparation

1. Ensure that the aerosol products are fully prepared for testing, including proper sealing and labeling for identification.
2. Prepare the necessary laboratory equipment and materials, including:
   • Agar plates or broth media for microbial growth
   • Incubators set to the appropriate temperature for microbial growth
   • Appropriate sampling tools, such as sterile swabs or pipettes
   • PPE, including gloves, lab coats, and goggles, to ensure safety during testing
3. Ensure that the laboratory environment is sterile and free from contamination. Clean and disinfect the testing area and all equipment before use.
4. Ensure that microbial testing media are prepared and sterilized according to the manufacturer’s guidelines.

5.2. Conducting the Microbial Limit Test

1. Collect the sample from the aerosol product using sterile tools to avoid contamination during the sampling process.
2. For each sample, transfer an appropriate volume or mass of the aerosol product to the prepared agar plates or into the test broth media. The specific volume or weight will depend on the type of test being conducted (e.g., for total aerobic count or yeast and mold count).
3. For the microbial growth test:
   • Place the inoculated agar plates or broth in the incubator at the specified temperature for the recommended duration (e.g., 48–72 hours for bacterial growth).
   • Monitor the samples periodically to check for microbial growth.
   • After incubation, observe the samples for visible colonies. Record the number of colonies and the type of microorganisms (e.g., bacteria, yeast, mold) based on colony morphology, color, and shape.
4. For the absence test:
   • After the specified incubation period, check for the absence of microbial growth. If no growth is observed, the product passes the microbial limit test.
   • If microbial growth is detected, the sample fails the test and corrective actions must be taken.
5. Record the results of the test, including the number of colonies, the type of microorganism, and any deviations or issues observed during the test.

5.3. Post-Test Actions

1. If microbial contamination is detected, identify the source of contamination and investigate potential causes (e.g., inadequate cleaning, improper storage conditions).
2. Remove the contaminated products from the production line, and take corrective actions such as re-cleaning, reprocessing, or adjusting formulation components as necessary.
3. Notify the Quality Assurance (QA) Manager and relevant personnel of the test failure and the corrective actions taken to resolve the issue.
4. Document the test results, including the type of microorganisms detected, the actions taken, and any additional testing conducted, in the Microbial Limit Testing Log (Annexure-1).

5.4. Calibration and Maintenance of Equipment

1. Ensure that all equipment used for microbial testing, such as incubators and testing media, is calibrated and maintained according to the manufacturer’s specifications.
2. Regularly inspect and clean laboratory equipment, such as pipettes, inoculating loops, and incubation chambers, to ensure accurate testing and prevent cross-contamination.
3. Document all calibration and maintenance activities in the Equipment Calibration Log (Annexure-2) and the Equipment Maintenance Log (Annexure-3).

5.5. Documentation and Record-Keeping

1. Document all microbial limit testing activities, including the test results, sample details, operator name, and any corrective actions taken, in the Microbial Limit Testing Log (Annexure-1).
2. Ensure that all test records are reviewed and approved by the QC team to confirm that the aerosol product meets the required microbial limits.
3. Store all microbial testing records in the document management system for future reference and audits.

5.6. Safety and Environmental Considerations

1. Ensure that all personnel involved in microbial testing are trained in the proper handling of microbiological materials, including the use of PPE, safe handling of contaminated samples, and proper disposal of waste.
2. Conduct all testing in a controlled laboratory environment to minimize the risk of contamination.
3. Dispose of any contaminated materials, such as petri dishes, used sampling tools, or waste media, in accordance with safety and environmental regulations.

6. Abbreviations

• GMP: Good Manufacturing Practice
• QC: Quality Control
• PPE: Personal Protective Equipment
• SOP: Standard Operating Procedure

7. Documents

1. Microbial Limit Testing Log (Annexure-1)
2. Equipment Calibration Log (Annexure-2)
3. Equipment Maintenance Log (Annexure-3)

8. References

This SOP is based on the following regulatory guidelines and industry standards:

• Good Manufacturing Practice (GMP) Guidelines
• FDA Code of Federal Regulations (CFR) Title 21, Part 211
• ISO 9001:2015 – Quality Management Systems

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Microbial Limit Testing Log

Sample ID	Test Date	Test Type	Microbial Growth	Operator Name	Remarks
MIC-12345	06/02/2025	Total Aerobic Count	No growth	Rajesh Patel	Test passed

Annexure-2: Equipment Calibration Log

Equipment ID	Calibration Date	Calibration Results	Operator Name	Remarks
MIC-001	06/02/2025	Pass	Rajesh Patel	No adjustments required

Annexure-3: Equipment Maintenance Log

Equipment ID	Maintenance Date	Tasks Performed	Operator Name	Remarks
MIC-001	06/02/2025	Cleaned and calibrated	Rajesh Patel	No issues found

12. Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By	Page No.	Ref. Point No.	Details of Revision
01/01/2024	V 1.0	Initial Release	First Issue	Anjali Sharma	Page 1	[Ref Point]	First Release
01/01/2025	V 2.0	Updated microbial limit testing procedure	To comply with updated GMP regulations	Anjali Sharma	Page 1	[Ref Point]	Updated procedures