Quality problems discovered after your reading glasses shipment arrives are expensive to fix — storage costs, re-shipping fees, damaged customer relationships, and in the worst cases, product returns. A proper quality inspection before shipment can catch 90% of issues before they become your problem.
Why B2B Buyers Must Inspect Before Shipping
Factory quality control and buyer quality expectations are not always aligned. What a factory considers “acceptable” may not meet your retail standards or regulatory requirements. Always inspect before the goods leave the factory’s port — it’s dramatically harder to resolve disputes after your goods are on a container ship.
The AQL Sampling Standard
The AQL (Acceptable Quality Level) system is the industry standard for eyewear inspection. AQL 2.5 is commonly used for reading glasses in retail distribution.
The process:
- Randomly select a sample set from the batch based on lot size (e.g., for 5,000 units, sample ~200 pieces)
- Inspect each sampled piece for critical, major, and minor defects
- Pass the lot if defect rate is below the AQL threshold; reject if above
| Defect Type | Description | AQL Standard |
|---|---|---|
| Critical | Safety hazard — sharp edges, lens detachment risk | 0 (zero tolerance) |
| Major | Functional — hinge failure, misalignment affecting fit | 2.5 |
| Minor | Cosmetic — minor scratches, uneven finish | 4.0 |
Frame Inspection Checklist
Structural Integrity
- Frame symmetry: Both sides of the frame should be mirror images; place on a flat surface to check
- Lens alignment: Lenses (pre-installed) should sit flush in the frame; no tilting or gaps
- Hinge function: Open and close temples 10 times — hinges should remain firm without becoming loose
- Spring hinge (if applicable): Test the flex — spring hinges should return to neutral position consistently
- Frame material consistency: Check for cracks, air bubbles (acetate), or surface imperfections
Metal Frame Specific Checks
- Nickel release test: Request factory’s EN 1811 test report for EU market compliance
- Soldering quality: Inspect all joints — no visible gaps, weak points, or cold solder
- Plating adhesion: Scratch lightly at an edge — plating should not peel
- Nosepad adhesion: Nosepads should be firmly attached; test by attempting to remove them by hand
TR90 and Polymer Frame Checks
- Flex test: Bend temples beyond normal opening angle — frame should return to shape without cracking
- Surface finish: No flow lines, sink marks, or discoloration from the injection molding process
- Color consistency: Check across all pieces in the sample — colors should match within tolerance
Pre-Installed Reader Lens Inspection
- Optical clarity: Look through each lens — no bubbles, scratches, or waves
- Power accuracy: Use a lensometer or calibrated focimeter to verify diopter matches your order (+/- 0.13D tolerance is standard)
- Lens centration: Optical center should align with pupil position — misaligned lenses cause visual discomfort
- Lens scratch coating: Lightly drag a fingernail across the surface — hard coat should resist light scratching
Packaging Inspection
- Barcode readability: Scan each UPC/EAN — must be GS1-compliant and match your product listing
- Power label accuracy: Each unit’s diopter label must be correct — wrong power labels are a serious safety issue
- Box/pouch condition: No tears, crushed corners, or print defects
- Assembly correctness: All components (cloth, case, warranty card) present per order spec
Third-Party Inspection Services
If you can’t inspect in person, consider hiring a third-party inspection company:
- Asia Quality Focus, QIMA, Bureau Veritas: Offer inspections starting at $150–$300 per day in China
- Pre-shipment inspection (PSI): Most common for B2B buyers; inspector visits factory before shipment
- During Production Inspection (DPI): Catches issues early in the production run — higher cost but best for large first orders
Dispute Resolution: What to Do When Inspection Fails
If AQL sampling fails:
- Document all defects with photos immediately
- Request the factory’s side-by-side inspection report
- Negotiate: rework at factory cost, price reduction, or replacement shipment
- For serious quality failures: invoke the payment hold (standard is 10–20% held until quality confirmed)
At Wenzhouframe, we welcome third-party inspections and provide full AQL sampling documentation for all B2B orders. We also maintain a defect replacement policy — contact us to discuss our quality guarantee terms.
