| Management System | Quality management system and scope of certification | Valid ISO 9001 certificate showing the correct legal entity, factory address, and relevant glass-processing activities | Certificate is current, traceable, and covers the actual production site | Check certificate number, validity, scope, issuing body, and certification database where available | No site-specific certificate |
| Product Safety | Applicable safety-glass standard | Test reports for tempered or laminated safety glass, such as EN 12150, EN 14449, ANSI Z97.1, or 16 CFR 1201, depending on the destination market | The standard matches the product type, thickness, and target market | Confirm report date, sample description, test laboratory, and tested construction | Generic report unrelated to the supplied specification |
| Optical Performance | Anti-glare performance, haze, gloss, reflectance, and transmission | Independent optical test report and a product datasheet defining measurement methods | Values are agreed in writing for the intended viewing distance, lighting, and application | Request sample measurements and compare them with the approved specification | Only uses the term “anti-glare” without measurable values |
| Surface Treatment | Etched, chemically treated, coated, or laminated anti-glare surface | Process description, coating or treatment datasheet, surface-energy information where relevant, and compatibility statement | The supplier can explain how the surface achieves glare reduction and how it affects cleaning and durability | Inspect samples under direct light, oblique light, and normal viewing conditions | Visible haze, uneven texture, pinholes, or inconsistent appearance |
| Glass Quality | Thickness, dimensions, flatness, edgework, scratches, chips, bubbles, and inclusions | Approved drawings, inspection standards, dimensional inspection records, and defect classification rules | Tolerance limits are defined before production and applied consistently to every batch | Use calibrated thickness gauges, measuring tools, visual inspection, and approved limit samples | Acceptance criteria are verbal or change after production |
| Tempering Control | Heat-treatment process, fragmentation, surface stress, and distortion | Furnace records, heat-treatment parameters, fragmentation test results, and inspection records | Process parameters are recorded for each batch and linked to the production lot | Review batch records and conduct third-party or incoming fragmentation checks when required | No batch-level furnace records |
| Lamination Control | Interlayer type, thickness, adhesion, bubbles, delamination, and edge quality | Interlayer technical datasheet, autoclave or laminating records, adhesion tests, and visual inspection reports | Interlayer specification and lamination cycle are documented and traceable | Inspect edges and glass under transmitted light; verify lot numbers and test records | Unidentified interlayer or unexplained substitutions |
| Durability | Resistance to humidity, temperature cycling, abrasion, chemicals, and cleaning agents | Durability test reports appropriate to the final application and surface technology | Testing reflects the actual indoor, outdoor, architectural, display, or furniture environment | Compare test conditions with the project environment and cleaning specification | Only short-term appearance samples are provided |
| Laboratory Control | Calibration and competence of measurement equipment | Calibration certificates for gloss meters, haze meters, spectrophotometers, thickness gauges, and other critical equipment | Equipment is calibrated at planned intervals and calibration status is identifiable | Review calibration dates, equipment IDs, standards used, and out-of-tolerance actions | Measurements cannot be linked to calibrated equipment |
| Independent Testing | Credibility of laboratory results | Reports from an accredited laboratory, preferably operating under ISO/IEC 17025 for the relevant tests | The laboratory scope includes the exact optical, safety, or durability test performed | Verify laboratory accreditation scope and report authenticity | Unverifiable laboratory or incomplete report |
| Production Capacity | Ability to maintain stable quality at the required volume | Production-flow chart, equipment list, monthly capacity statement, shift plan, and recent batch records | Capacity is supported by equipment and staffing, not only by a sales estimate | Conduct a remote or on-site factory audit and compare capacity with current orders | Capacity changes significantly between quotations |
| Traceability | Connection between raw materials, processing, inspection, and shipment | Lot-number system, production traveler, inspection report, packing list, and shipment records | A finished panel can be traced back to glass, interlayer or coating lot, machine, date, and inspector | Select a shipped lot and request the complete traceability file | Only invoice-level traceability is available |
| Incoming Inspection | Control of float glass, interlayers, coatings, packaging materials, and accessories | Incoming inspection plans, supplier certificates, material identification records, and nonconformance reports | Critical materials are checked before release to production | Review sampling frequency, acceptance criteria, and rejected-material controls | Materials enter production without documented inspection |
| Final Inspection | Release criteria before packing and shipment | Final inspection checklist covering dimensions, appearance, optical values, safety properties, labeling, and packaging | Every shipment is released against a signed inspection record | Compare the inspection record with the purchase order and approved sample | Inspection is performed only after customer complaints |
| Packaging & Logistics | Protection against breakage, moisture, edge damage, and surface contamination | Packing specification, loading photos, crate design, moisture protection method, and handling instructions | Packaging is suitable for the glass size, weight, transport route, and storage period | Approve a packing sample and inspect loading procedures before mass shipment | Insufficient separators, unstable crates, or no loading controls |
| Corrective Action | Response to defects, claims, and repeated nonconformities | Nonconformance reports, root-cause analysis, corrective-action records, and effectiveness checks | Issues are analyzed using documented root-cause and preventive-action procedures | Ask for anonymized examples showing closure and verification of corrective actions | Repeated defects are blamed on transport or installation without investigation |
| Environmental & Safety Compliance | Environmental management, worker safety, and chemical handling | Relevant ISO 14001 or ISO 45001 certificates, chemical safety documents, waste records, and workplace controls | Certificates and controls apply to the actual manufacturing site | Review certificate scope and audit chemical storage, waste handling, and safety signage | Certificates belong to another site or entity |
| Commercial Reliability | Specification control, lead time, warranty, and change notification | Signed technical specification, quality agreement, warranty terms, change-control procedure, and delivery records | No material, process, or subcontracting change occurs without written approval | Include approval procedures and measurable acceptance criteria in the purchase contract | Unapproved substitutions or vague warranty language |