vision system cameras

Operational Qualification (OQ):

• Running empty and dummy blister cycles
• Testing control panel functionality, alarms, interlocks
• Testing different temperature and pressure ranges for sealing plates

Performance Qualification (PQ):

• Producing multiple full-scale commercial batches
• Monitoring sealing integrity, foil cutting precision, and product alignment
• Collecting and trending critical process parameters (CPPs)

Each stage should include predefined acceptance criteria, raw data, and QA signoff.

3. Critical Parameters in Blister Packaging Validation

Blister line validation focuses on the following critical parameters:

• Sealing plate temperature (°C)
• Sealing pressure (N/cm²)
• Sealing dwell time (seconds)
• Forming station vacuum level
• Foil/aluminum feed tension and positioning

Example Acceptance Range:

Parameter	Set Point	Acceptance Range
Sealing Temp	200°C	±5°C
Sealing Pressure	2.5 N/cm²	±0.2 N/cm²
Dwell Time	0.8 sec	±0.1 sec

Document these in the PQ protocol along with sample sizes, batch numbers, and deviations (if any).

4. Heat Sealing Integrity and Leak Testing

Sealing integrity is verified using the following tests:

• Dye Penetration Test: Detects microleaks by vacuum-submerging blister in methylene blue solution
• Bubble Leak Test: Used for transparent films to detect air escape under water
• Peel Test: Measures the force required to separate seal layers (min 1.5 N for aluminum seals)

Each test should include positive and negative controls. Acceptance criteria should ensure no leaks or delamination in test samples.

5. Vision System and Print Verification

Automated vision systems are validated to ensure correct print, position, and absence of defects:

• OCR/OCV for batch number and expiry date
• Barcode or 2D Data Matrix validation (as per serialization)
• Blister cavity fill inspection – presence/absence detection
• Detection of color variation and misalignment

Vision system validation should include false positive and false negative scenarios using intentionally incorrect samples.

6. Line Clearance and GMP Compliance

Line clearance ensures that the line is free of materials from the previous batch and is ready for use. Key elements:

• Visual inspection of packaging area, hopper, conveyor, scrap bins
• Documentation of clearance activity in logbook
• Checklist verification and QA signoff
• Label printer purge and roll reset

Line clearance is mandatory before each batch and should be part of every SOP governing blister packaging lines.

7. Cleaning Validation for Blister Lines

Blister packaging lines that process multiple products must undergo validated cleaning to prevent cross-contamination. Validation should include:

• Swab and rinse sampling from forming station, sealing plate, guides
• Worst-case product selection based on solubility, potency
• Acceptance limits: MACO & PDE based calculations

Example Acceptance Limit (API A): MACO = 0.9 µg/cm², Swab LOD = 0.5 µg/cm²

For cleaning limit templates, visit PharmaValidation.in.

8. Strip Packaging: Special Considerations

Strip packaging involves continuous sealing between two foil layers, which presents unique validation challenges:

• Constant sealing pressure and speed synchronization
• Perforation quality validation
• Product misfeed rejection mechanism
• Print legibility on continuous strip (lot & expiry)

Strip packaging lines should undergo separate OQ/PQ with defined acceptance criteria and dummy runs.

9. Revalidation and Change Control

Any of the following changes trigger revalidation:

• Change in foil supplier or GSM (grams per square meter)
• Modification to sealing jaw design or temperature sensor
• Label content or layout change
• Software or vision system upgrades

Such changes must follow documented change control procedures and be justified with documented impact assessments.

10. Documentation and Compliance Readiness

Blister line validation documentation must include:

• IQ, OQ, PQ protocols and reports
• Calibration and maintenance records
• Cleaning validation reports
• Deviation logs and CAPA (if applicable)
• Vision system validation results
• Batch-specific line clearance forms

Ensure that validation files are readily retrievable for GMP inspections. Refer to pharmaregulatory.in for FDA inspection readiness checklists.

Conclusion

Blister line validation is a comprehensive, cross-functional activity that ensures product integrity, packaging compliance, and regulatory readiness. By validating critical parameters like sealing temperature, line clearance, vision inspection, and equipment functionality, pharmaceutical manufacturers can maintain consistent quality and pass regulatory audits with confidence.

For validation templates, equipment qualification checklists, and sample PQ protocols, visit PharmaValidation.in.