1. GENERAL INSPECTION INFORMATION
Product Name: Louvered Solid Wood Door
Applicable Origin: Vietnam / Thailand / Cambodia
Export Destination: USA / European Union / Canada / Australia
Inspection Standard: International Furniture Inspection Standard, EU EN Standards, US ASTM Wood Door Specification, AQL 0.0 (Critical) / 2.5 (Major) / 4.0 (Minor)
Defect Classification Definition (Global Unified Industry Terminology)
- Critical Defect (CRI): Safety hazards, regulatory non-compliance, structural failure, zero tolerance, 100% reject
- Major Defect (MAJ): Obvious functional impairment, severe appearance defect affecting sales, non-acceptable for export
- Minor Defect (MIN): Slight cosmetic deviation, no impact on structure & function, within international acceptable tolerance
Inspection Scope: Visual Appearance Inspection, Internal Structural Inspection, Dimensional Tolerance Inspection, Functional Performance Inspection, Laboratory Physical & Chemical Testing
2. VISUAL APPEARANCE INSPECTION (SURFACE & LOUVER DETAILS)
Industry Standard Basis: ASTM D3134 (Wood Surface Defect Grading), EN 971-1 (Coating Surface Specification)
| Inspection Item | Professional Defect Terminology | Acceptable Standard (MIN) | Unacceptable Standard (MAJ/CRI) | Defect Level |
|---|---|---|---|---|
| Wood Grain & Color Consistency | Heterochromia, Grain Mismatch, Tone Variation | Slight tone deviation under natural light, invisible from 1m distance; consistent grain layout of louver slats | Obvious heterochromia, severe grain disorder, color difference exceeding industry color tolerance; inconsistent louver grain arrangement | MAJ |
| Surface Coating Finish | Orange Peel, Pinhole, Blister, Crazing, Flow Mark, Sagging | Micro pinholes ≤2pcs per square meter, no concentrated distribution; slight uniform orange peel texture without hand feeling difference | Visible blister, coating crazing, sagging & flow mark; concentrated pinholes; peeling coating | MAJ |
| Surface Damage | Scuff, Scratch, Dent, Chip, Bruise | Fine superficial scratch ≤5mm, no paint penetration; tiny dent depth ≤0.2mm, no obvious visual impact | Deep scratch penetrating coating, length >5mm; obvious dent, edge chipping, wood fiber damage | MAJ |
| Wood Knot Defect | Dead Knot, Loose Knot, Over-sized Live Knot, Knot Void | Solid live knot ≤3mm, stable texture, no cracking; no loose/dead knot on visible surface | Dead knot, loose knot, falling knot void; live knot >3mm with cracking tendency | MAJ |
| Louver Slat Uniformity | Slat Misalignment, Uneven Gap, Slat Warpage, Inconsistent Angle | Slat gap deviation ≤1mm, angle tolerance ±1°, no visible misalignment at normal viewing angle | Slat gap deviation >1mm, distorted angle, obvious warpage, staggered slat arrangement affecting appearance | MAJ |
| Edge & Corner Treatment | Burr, Sharp Edge, Edge Chipping, Unsealed Edge | Slight tiny burr removable by fine polishing, no sharp edge; complete edge sealing | Persistent burr, sharp edge causing scratch risk; edge chipping, incomplete edge sealing | MAJ |
| Surface Contamination | Stain, Oil Mark, Dust Inclusion, Foreign Particle | Invisible tiny foreign particles, no residual stain after cleaning | Persistent oil stain, color stain, embedded foreign particles affecting surface finish | MIN/MAJ |
3. INTERNAL STRUCTURE INSPECTION (CORE & INNER WORKMANSHIP)
Industry Standard Basis: EN 1121 (Wood Door Structural Strength), ASTM F892 (Door Construction Specification)
| Inspection Item | Professional Defect Terminology | Acceptable Standard (MIN) | Unacceptable Standard (MAJ/CRI) | Defect Level |
|---|---|---|---|---|
| Core Material Consistency | Material Mismatch, Hollow Core Defect, Filler Shortage | Consistent solid wood core as customized, uniform filler density, no local hollow | Core material inconsistent with contract specification; serious hollow core, insufficient filler affecting structural stability | CRI |
| Internal Splicing Joint | Joint Gap, Open Seam, Mis-splice, Adhesive Void | Splicing gap ≤0.5mm, full adhesive penetration, no open seam under pressure test | Joint gap >0.5mm, open seam, adhesive void, loose splicing structure | MAJ |
| Wood Moisture Content (Internal) | Excessive Moisture, Low Moisture, Uneven Moisture Distribution | Moisture content 8%–12% (US/EU standard), uniform internal moisture | Moisture ＜6% or ＞14%; uneven moisture causing warping risk | MAJ |
| Internal Reinforcement Structure | Reinforcement Missing, Offset Reinforcement, Loose Fixing | Reinforcement plate/bar installed in standard position, firm fixing, no offset | Missing reinforcement at hinge/lock position, loose fixing, serious offset affecting load-bearing | CRI |
| Anti-corrosion & Mildew Treatment | Mildew Spot, Corrosion Residue, Untreated Inner Surface | Complete internal anti-mildew & anti-corrosion treatment, no mildew trace | Visible internal mildew spot, corrosion residue, missing protective treatment | MAJ |
| Louver Internal Connection | Loose Connection, Slat Detachment, Structural Gap | All louver slats firmly connected, no loose shake under slight vibration | Loose louver connection, slat shaking, partial detachment, structural gap | MAJ |
4. DIMENSIONAL & TOLERANCE INSPECTION
Industry Standard Basis: ISO 2859-1 (Sampling Standard), EN 1529 (Door Dimensional Tolerance)
| Inspection Item | Tolerance Specification | Acceptable | Unacceptable | Defect Level |
|---|---|---|---|---|
| Door Leaf Height & Width | ±2mm | Deviation within ±2mm | Deviation over ±2mm | MAJ |
| Door Leaf Thickness | ±1mm | Deviation within ±1mm | Deviation over ±1mm | MAJ |
| Diagonal Difference | ≤2mm | Diagonal length difference ≤2mm | Diagonal difference ＞2mm (causes distortion & poor fitting) | MAJ |
| Door Frame & Leaf Gap | Top:1.5–3mm, Side:2–5mm, Bottom:5–8mm | Gap within standard range, uniform clearance | Gap out of range, uneven gap causing jamming/air leakage | MAJ |
| Flatness & Verticality | Flatness ≤1.5mm/m, Verticality ≤2mm/m | Flatness & verticality within tolerance | Excessive flatness/verticality deviation causing warping & fitting failure | MAJ |
5. FUNCTIONAL PERFORMANCE INSPECTION
Industry Standard Basis: ASTM F1576 (Door Operation Performance), EN 12219 (Door Functional Safety)
| Inspection Item | Defect Terminology | Acceptable Standard | Unacceptable Standard | Defect Level |
|---|---|---|---|---|
| Opening & Closing Operation | Binding, Snagging, Abnormal Noise, Self-closing/self-opening | Smooth opening/closing, no snagging, no abnormal friction noise; 45° static placement stable | Obvious binding & snagging, harsh friction noise; automatic opening/closing due to unvertical installation | MAJ |
| Hardware Matching & Operation | Hardware Mis-fit, Loose Hinge, Latch Failure, Jammed Key | Hinge fixed firmly, lock latch flexible, key rotation smooth, complete hardware accessories | Loose hinge, lock failure, key jamming, missing/wrong hardware | MAJ |
| Louver Adjustment Function | Adjustment Stuck, Slat Inflexible, Angle Fixed Failure | Louver angle adjustable freely, uniform adjustment damping, no stuck | Louver adjustment stuck, inflexible rotation, unable to fix angle | MAJ |
6. LABORATORY PROFESSIONAL TESTING ITEMS (EXPORT STANDARD)
Compliance Standard: US CARB P2, EU E1 Emission Standard, AU AS/NZS 2208, Canada CSA O121
| Laboratory Test Item | International Standard Requirement | Unacceptable Test Result (CRI) |
|---|---|---|
| Formaldehyde Emission Test | EU E1: ≤0.124mg/m³; US CARB P2 Compliant | Exceed standard limit, fail environmental certification (prohibited for EU/US/CA/AU export) |
| Wood Moisture Content Test | 8%–12% (Global wooden door export standard) | Moisture out of range, causing post-transport warping, cracking, mildew |
| Surface Coating Adhesion Test | ASTM D3359 Grade 4B–5B, no coating peeling | Coating peeling, adhesion grade ＜4B |
| Impact Resistance Test | EN 1529: No structural damage & obvious dent after standard impact | Crack, dent, structural deformation after impact test |
| Humidity & Temperature Cycling Test | No warping, cracking, delamination after cyclic test | Visible warping, splicing crack, coating delamination after test |
| Mold & Corrosion Resistance Test | ASTM D4587: No mildew growth & metal corrosion | Mildew breeding, hardware corrosion, wood decay |
| Structural Load-bearing Test | No deformation & connection loosening under standard load | Permanent deformation, connection failure, structural damage |
7. FINAL INSPECTION JUDGMENT RULES
- Critical Defect: 100% batch rejection, no tolerance, unqualified for all export markets
- Major Defect: Judge batch qualification per AQL 2.5; excess quantity = batch reject
- Minor Defect: Judge batch qualification per AQL 4.0; slight cosmetic defects within tolerance allowable
- Laboratory Test Failure: All test item non-compliance = batch full rejection, prohibited from shipment to US/EU/CA/AU
8. AQL SAMPLING & ACCEPTANCE JUDGMENT TABLE (STANDARD EXPORT INSPECTION)
Applicable Standard: ISO 2859-1:2019 General Inspection Level II, Normal Inspection, Single Sampling Plan, Non-Tightened Inspection (Default for USA/EU/CA/AU Wooden Door Export)
Unified AQL Threshold: Critical Defect = 0.0 | Major Defect = 2.5 | Minor Defect = 4.0 (Global Furniture Export Universal Standard)
| Lot Size (Batch Quantity) | Sample Inspection Quantity | Critical Defect (AQL 0.0)Accept / Reject | Major Defect (AQL 2.5)Accept / Reject | Minor Defect (AQL 4.0)Accept / Reject |
|---|---|---|---|---|
| 2–8 | 2 | 0 / ≥1 | 0 / ≥1 | 0 / ≥1 |
| 9–15 | 3 | 0 / ≥1 | 0 / ≥1 | 1 / ≥2 |
| 16–25 | 5 | 0 / ≥1 | 0 / ≥1 | 1 / ≥2 |
| 26–50 | 8 | 0 / ≥1 | 1 / ≥2 | 2 / ≥3 |
| 51–90 | 13 | 0 / ≥1 | 1 / ≥2 | 3 / ≥4 |
| 91–150 | 20 | 0 / ≥1 | 2 / ≥3 | 5 / ≥6 |
| 151–280 | 32 | 0 / ≥1 | 3 / ≥4 | 7 / ≥8 |
| 281–500 | 50 | 0 / ≥1 | 5 / ≥6 | 10 / ≥11 |
| 501–1200 | 80 | 0 / ≥1 | 7 / ≥8 | 14 / ≥15 |
| 1201–3200 | 125 | 0 / ≥1 | 10 / ≥11 | 21 / ≥22 |
AQL SAMPLING SUPPLEMENT RULES (EXPORT STANDARD)
- Critical Defect Zero Tolerance: Any single critical defect found during inspection results in immediate batch rejection, applicable to all Vietnam/Thailand/Cambodia production batches for US/EU/CA/AU markets.
- Sampling Randomness Requirement: Inspection samples must be randomly selected from different production layers, packaging cartons and container loading positions to ensure representativeness.
- Defect Cumulative Judgment: Major and Minor defects are counted separately; cross-type defect accumulation is not allowed for qualification judgment.
- Re-inspection Regulation: Rejected batches can be fully sorted and reworked, then apply secondary sampling inspection; secondary failure results in permanent batch rejection.
9. ON-SITE INSPECTION PHOTO EVIDENCE CHECKLIST (MANDATORY FOR EXPORT ARCHIVE)
Industry Standard Basis: Global Third-Party Inspection Photo Documentation Specification, EU/US Export Customs & Client Audit Requirement
Rule: All photos must be clear, unedited, full-scene & close-up dual shots; defective positions must be marked with inspection tag/sticker
| No. | Photo Shooting Item | Shooting Requirement & Standard | Photo Taken (√/×) |
|---|---|---|---|
| 1 | Batch Overall Scene | Capture full batch stacking status, packaging condition, production batch label & origin marking | |
| 2 | Product Overall Appearance | Front & back full view of door leaf, overall louver slat arrangement, whole surface finish status | |
| 3 | Louver Slat Detail Shot | Close-up of slat gap uniformity, angle consistency, connection tightness, surface finish of slat edge | |
| 4 | Surface Defect Close-up | Targeted shooting for scratch, dent, stain, pinhole, orange peel, knot defect and other cosmetic issues | |
| 5 | Edge & Corner Treatment Detail | Close-up of door edge sealing, corner polishing, no burr/chipping verification | |
| 6 | Dimensional Inspection Verification | Shoot caliper/tape measure reading, diagonal test, flatness & verticality inspection process | |
| 7 | Functional Operation Test | Photo of door opening/closing status, louver angle adjustment, hardware flexible operation | |
| 8 | Internal Structure Sampling Shot | Partial sampling shooting of core material, splicing joint, reinforcement structure, adhesive filling status | |
| 9 | Moisture Content Test Record | Shoot moisture meter numerical reading on door surface & internal wood structure | |
| 10 | Defect Marking & Sorting Scene | Shoot marked defective products, classified sorting of MIN/MAJ/CRI defect goods | |
| 11 | Packaging & Container Loading Status | Shoot finished packaging, carton marking, container stacking environment for export shipment | |
| 12 | Laboratory Test Sample Retention | Shoot reserved test samples, test report data sheet & certification documents |
10. KEY FACTORS AFFECTING LOUVERED SOLID WOOD DOOR QUALITY (EXPORT GRADE)
Industry Standard Basis: ASTM D245 (Wood Grading Standard), EN 335 (Wood Durability Specification), International Wooden Door Export Quality Control Guideline
10.1 Raw Material Factors (Root Quality Influence)
- Wood Species Consistency: Mixed wood species usage causes inconsistent density, shrinkage & expansion coefficient, leading to uneven deformation and color difference after finishing; unqualified raw wood with excessive loose knots/dead knots directly reduces structural stability and surface grade.
- Raw Wood Moisture Content: Uncontrolled pre-production wood moisture (out of 8%–12% standard range) is the core cause of post-production warping, cracking, mildew and louver slat distortion; ununiform moisture distribution leads to asymmetric structural stress.
- Raw Material Grading: Failure to grade wood by grain direction, texture density and defect level results in concentrated surface defects, inconsistent louver slat texture and poor overall appearance uniformity.
10.2 Production & Processing Factors
- Louver Processing Precision: Inaccurate slat cutting angle, uneven gap milling and inconsistent trimming size cause slat misalignment, unsmooth adjustment and overall appearance disorder; low processing precision leads to assembly tolerance overrun.
- Splicing & Adhesive Technology: Insufficient adhesive penetration, uneven glue coating and irregular splicing gap cause adhesive void, open seam and loose internal structure; unqualified environmental adhesive leads to formaldehyde emission exceeding export standards.
- Surface Coating Process: Unstandardized priming/topcoating spraying, improper drying temperature & humidity lead to orange peel, pinhole, blister and coating crazing; insufficient coating adhesion process causes post-transport peeling and scratch damage.
- Edge Sealing & Polishing Workmanship: Incomplete edge sealing causes wood moisture re-absorption and mildew; insufficient polishing leaves burrs and sharp edges, affecting safety and appearance grade.
10.3 Structural & Reinforcement Factors
- Reinforcement Layout Rationality: Missing or offset reinforcement at hinge and lock bearing positions leads to structural deformation and loose hardware installation after long-term use, failing EU/US structural load-bearing tests.
- Louver Connection Structure: Unstandardized fixed connection process causes slat shaking, detachment and angle fixation failure, reducing product durability and functional qualification rate.
- Internal Filling Uniformity: Uneven core filler density and local hollow defects lead to inconsistent door leaf flatness, poor sound insulation performance and structural instability.
10.4 Environmental & Storage Factors (Origin Plant Control)
- Workshop Temperature & Humidity Control: Unstable production environment humidity in Vietnam/Thailand/Cambodia factories causes secondary moisture absorption or dehydration of semi-finished products, inducing subsequent warping and cracking.
- Warehouse Storage Condition: Unsealed storage, damp ground and poor ventilation lead to wood mildew, hardware corrosion and surface stain contamination before shipment.
- Packaging & Transportation Protection: Unreasonable buffer packaging causes extrusion dent and scratch during container transportation; lack of moisture-proof packaging leads to humidity damage in cross-ocean shipment.
10.5 Testing & Compliance Factors
- Environmental Index Control: Unqualified formaldehyde emission and harmful substance content fail US CARB P2, EU E1 and Australian standard certification, resulting in export rejection.
- Physical Performance Stability: Unqualified impact resistance, temperature & humidity cycling resistance and mold resistance lead to product failure in overseas after-sale use and customer claim risk.
11. INSPECTION REMARKS & SIGNATURE
Inspection Date: _______________
Production Origin: _______________ (Vietnam/Thailand/Cambodia)
Export Destination: _______________ (USA/EU/Canada/Australia)
Batch Quantity: _______________ Inspected Quantity: _______________
Total Critical Defects: _______________ Total Major Defects: _______________ Total Minor Defects: _______________
Inspection Result: □ PASS □ FAIL
Inspector Signature: _______________ Auditor Signature: _______________
Official Remarks & Non-conformity Description: ________________________________________________________________________ ________________________________________________________________________
Inspection Date: _______________
Production Origin: _______________ (Vietnam/Thailand/Cambodia)
Export Destination: _______________ (USA/EU/Canada/Australia)
Batch Quantity: _______________ Inspected Quantity: _______________
Total Critical Defects: _______________ Total Major Defects: _______________ Total Minor Defects: _______________
Inspection Result: □ PASS □ FAIL
Inspector Signature: _______________ Auditor Signature: _______________
Remarks: ________________________________________________________________________
Inspection Date: _______________
Production Origin: _______________ (Vietnam/Thailand/Cambodia)
Export Destination: _______________ (USA/EU/Canada/Australia)
Batch Quantity: _______________ Inspected Quantity: _______________
Inspection Result: □ PASS □ FAIL
Inspector Signature: _______________ Auditor Signature: _______________
