What to Look for When Checking for Impurities

Inspection Checklist

Title: What to Look for When Checking for Impurities

Department: Quality Control / Production
Location: Cathode & Anode Lines, Mixing, Coating, and Slitting Areas
Document Owner: Quality Assurance Manager
Last Reviewed: [Date]

1. Purpose

To provide a standardised checklist for identifying potential impurities during production, ensuring product quality and regulatory compliance.

2. Scope

Applies to operators, quality inspectors, and maintenance personnel conducting in-process or post-process inspections.

3. Inspection Triggers

Start-of-shift line clearance
Changeover between batches
After equipment maintenance or cleaning
Routine hourly checks during production

4. Key Impurity Types and Indicators

A. Foreign Particles

Dust, fibres, or hair in mixing tanks or slurry
Metallic fragments in the final coated rolls
Plastic or packaging residue in processing zones

B. Cross-Contamination

Signs of previous batch material in the current output
Mismatched colour or texture in the slurry or coating
Residual powder or liquid in pipelines or tanks

C. Surface Defects

Pinholes, streaks, or bubbles on coated foil
Uneven coating thickness or spots
Scratches or dents on processed material

D. Environmental Contamination

Condensation on walls, ceiling, or ducts
Open doors, compromising clean/dry room pressure
Unauthorised entry without full PPE

5. Inspection Procedure

Perform visual inspection under proper lighting.
Use lint-free wipes to test for residue if needed.
Use a UV or inspection lamp for foreign particle checks.
Document all observations and deviations.

6. Reporting & Response

Report anomalies immediately to Line Lead or QA.
If impurities are found:
- Quarantine affected the material
- Record lot/batch number and location
- Initiate non-conformance procedure

7. Documentation

Use the Impurity Inspection Log (paper or digital)
Include date, time, product ID, area inspected, and findings
Attach photos where applicable

8. Reminders

Never proceed if an impurity is suspected but unresolved
Always verify the cleaning of equipment between material changes
Report recurring impurity patterns to supervisors

End of Checklist