Understanding AQL 2.5 Sampling Tables & Accept/Reject Limits
Lesson Contents Overview
Learning Objectives
Comprehensive Technical GuidanceTextbook & Training SOP
Understanding AQL 2.5 Sampling Tables & Accept/Reject Limits
═══════════════════════════════════════════════════════════════════════════════ MODULE 01: ISO 2859-1 AQL SAMPLING TABLES & MECHANICS LESSON 01.01: UNDERSTANDING AQL 2.5 SAMPLING TABLES & ACCEPT/REJECT LIMITS ═══════════════════════════════════════════════════════════════════════════════ [Course: AQL 2.5 Quality Inspection & QA Masterclass] [Next: 01.02 Inspection Levels & Code Letters ➡️]
1. Introduction: The Foundation of Apparel Quality Auditing
In the global garment manufacturing industry, producing hundreds of thousands of shirts, trousers, jackets, or intimate apparel pieces every day makes 100% finished inspection by buyers economically impossible and logistically unfeasible. Inspecting every single seam, button, hem, and zipper on 50,000 garments would take weeks, dramatically increase labor costs, and still fail to catch human inspection fatigue errors.
To solve this challenge, international trade relies on statistical quality control sampling governed by the ISO 2859-1 (International Organization for Standardization) and ANSI/ASQ Z1.4 (American National Standards Institute / American Society for Quality) standards, historically derived from the US military standard MIL-STD-105E.
At the heart of this statistical framework is the Acceptable Quality Limit (AQL), most commonly set at AQL 2.5 for Major defects and AQL 4.0 for Minor defects, alongside AQL 0.0 (Zero Tolerance) for Critical safety defects.
┌─────────────────────────────────────────────────────────────────────────────┐ │ THE AQL SAMPLING EQUILIBRIUM │ │ │ │ BUYER (CONSUMER'S RISK - BETA) FACTORY (PRODUCER'S RISK - ALPHA) │ │ Wants zero defects, perfect fit, Wants fast shipment clearance, │ │ flawless aesthetics, safe garments. zero unnecessary carton rework. │ │ ▲ ▲ │ │ └───────────────┬─────────────────┘ │ │ │ │ │ ISO 2859-1 / ANSI/ASQ Z1.4 │ │ STATISTICAL SAMPLING PLAN │ │ (Scientific Balance of Risk & Cost) │ └─────────────────────────────────────────────────────────────────────────────┘
2. What AQL Really Means (And What It Does NOT Mean)
One of the most dangerous misconceptions on the garment factory floor is that "AQL 2.5 means our shipment is allowed to have 2.5% defective garments."
This is fundamentally incorrect.
The True Definition
Acceptable Quality Limit (AQL): The maximum percent nonconforming (or maximum number of defects per hundred units) that, for the purposes of sampling inspection, can be considered satisfactory as a process average.
What AQL Is vs. What It Is Not
| Aspect | What AQL Is (True Principle) | What AQL Is NOT (Common Fallacy) |
|---|---|---|
| Process Benchmark | A statistical threshold that validates whether a factory's ongoing production process is stable and acceptable. | A contractual permission slip to intentionally ship 2.5% defective garments. |
| Pass/Fail Decision | A formal mathematical rule to decide whether to Accept or Reject a specific production lot based on sample findings. | A guarantee that 100% of uninspected garments in the remaining cartons are defect-free. |
| Statistical Risk | A mathematically designed curve balancing Producer's Risk (Alpha ≈ 5%) and Consumer's Risk (Beta). | An arbitrary guessing system used by quality auditors. |
| Defect Allowance | A boundary condition: lots with process averages ≤ 2.5% have a ≥ 95% probability of acceptance. | A target defect quota for sewing operators and line quality controllers. |
3. Garment Defect Classification: Critical, Major, and Minor
Before an inspector can count defects against AQL limits, every defect observed during the audit must be categorized according to its severity classification.
┌─────────────────────────────────────────────────────────────────────────────┐ │ GARMENT DEFECT SEVERITY PYRAMID │ │ │ │ ▲ │ │ / \ │ │ / \ │ │ / CRIT\ AQL 0.0 (Ac=0, Re=1) │ │ /───────\ Zero-Tolerance: Safety & Legal │ │ / MAJOR \ AQL 2.5 (Standard) │ │ /───────────\ Functional & Visual Failure │ │ / MINOR \ AQL 4.0 (Standard) │ │ /───────────────\ Cosmetic & Workmanship Flaws │ │ ─────────────────── │ └─────────────────────────────────────────────────────────────────────────────┘
1. Critical Defects (AQL 0.0 / Zero Tolerance: Ac = 0, Re = 1)
A Critical defect is any condition that compromises consumer safety, violates international regulations, or poses legal liability.
- Sharp Foreign Objects: Broken sewing needle fragment embedded in garment, sharp staples, loose pins.
- Child Safety Hazards: Loose buttons or snap fasteners on infant garments (<90N pull strength), drawstrings exceeding legal lengths on kids' hoodies.
- Biological / Chemical Contamination: Live insects, mold/mildew spores, blood stains, toxic chemical smells (formaldehyde).
- Regulatory Non-Compliance: Missing country of origin label, incorrect fiber composition label, flammability test failure.
- Inspection Outcome: A SINGLE CRITICAL DEFECT FAILS THE ENTIRE SHIPMENT IMMEDIATELY, regardless of lot size.
2. Major Defects (AQL 2.5 Standard)
A Major defect is a structural, functional, or severe aesthetic flaw that causes the garment to fail its intended purpose, impair fit, or lead to retail customer returns.
- Structural Seam Failures: Open seams >1/4" (6 mm), cracked stitches under tension, missing bar-tacks on stress points.
- Fabric & Material Flaws: Fabric holes, dropped loops, horizontal knit ladders, torn warp threads, severe pilling.
- Dimensional Out-of-Tolerance: Key measurements exceeding buyer tolerance (e.g., chest width ±1.5 cm on a ±0.75 cm spec).
- Color & Shading Issues: Noticeable panel-to-panel shade variation (Delta E > 1.0 or Grade <4 on Gray Scale), severe color bleeding.
- Functional Hardware Failures: Jammed or broken zippers, missing buttonholes, inoperable snap buttons.
3. Minor Defects (AQL 4.0 Standard)
A Minor defect is a slight cosmetic imperfection or workmanship blemish that does not impair the function, durability, or fit of the garment, and is unlikely to result in a retail return.
- Thread Trimming Flaws: Uncut thread ends >1/2" (12 mm) that are non-critical and easily trimmed.
- Slight Sewing Irregularities: Minor stitch run-off at inside waistband facing, slight SPI variation (11 SPI instead of 12 SPI).
- Minor Aesthetic Blemishes: Removable chalk/pencil marks, slight iron shine/glaze, care label stitched 2 mm off-center inside side seam.
To execute an AQL inspection, QA professionals use two standardized tables:
- Table 1: Sample Size Code Letters (Determines the Code Letter based on Lot Size and Inspection Level).
- Table 2-A: Single Sampling Plans for Normal Inspection (Determines the Sample Size and the specific Accept/Reject limits for each AQL).
Step 1: Finding the Sample Size Code Letter (Table 1)
Cross-reference the Lot Size (Total Garment Quantity) with General Inspection Level II (the default standard for ready-made garments).
LOT SIZE RANGE LEVEL I LEVEL II (Default) LEVEL III ───────────────────────────────────────────────────────────────────────── 2 to 8 A A B 9 to 15 A B C 16 to 25 B C D 26 to 50 C D E 51 to 90 C E F 91 to 150 D F G 151 to 280 E G H 281 to 500 F H J 501 to 1,200 G J K 1,201 to 3,200 H K L 3,201 to 10,000 J L M 10,001 to 35,000 K M N 35,001 to 150,000 L N P 150,001 to 500,000 M P Q 500,001 and over N Q R
Step 2: Locating the Sample Size & Limits in Table 2-A
CODE SAMPLE AQL 0.65 AQL 1.0 AQL 1.5 AQL 2.5 (Major) AQL 4.0 (Minor) LETTER SIZE Ac / Re Ac / Re Ac / Re Ac / Re Ac / Re ─────────────────────────────────────────────────────────────────────────────────────────── A 2 ↓ (0/1) ↓ (0/1) ↓ (0/1) ↓ (0/1) ↓ (0/1) B 3 ↓ (0/1) ↓ (0/1) ↓ (0/1) ↓ (0/1) ↓ (0/1) C 5 ↓ (0/1) ↓ (0/1) ↓ (0/1) ↓ (0/1) ↓ (0/1) D 8 ↓ (0/1) ↓ (0/1) ↓ (0/1) ↓ (0/1) 0 / 1 E 13 ↓ (0/1) ↓ (0/1) ↓ (0/1) 0 / 1 1 / 2 F 20 ↓ (0/1) ↓ (0/1) 0 / 1 1 / 2 2 / 3 G 32 ↓ (0/1) 0 / 1 1 / 2 2 / 3 3 / 4 H 50 0 / 1 1 / 2 2 / 3 3 / 4 5 / 6 J 80 1 / 2 2 / 3 3 / 4 5 / 6 7 / 8 K 125 2 / 3 3 / 4 5 / 6 7 / 8 10 / 11 L 200 3 / 4 5 / 6 7 / 8 10 / 11 14 / 15 M 315 5 / 6 7 / 8 10 / 11 14 / 15 21 / 22 N 500 7 / 8 10 / 11 14 / 15 21 / 22 ↑ (21/22) P 800 10 / 11 14 / 15 21 / 22 ↑ (21/22) ↑ (21/22) Q 1,250 14 / 15 21 / 22 ↑ (21/22) ↑ (21/22) ↑ (21/22) R 2,000 21 / 22 ↑ (21/22) ↑ (21/22) ↑ (21/22) ↑ (21/22)
5. The Critical "Arrow Rules" in AQL Tables
Notice the downward arrows (↓) and upward arrows (↑) in Table 2-A. These arrows represent a vital statistical mandate:
┌─────────────────────────────────────────────────────────────────────────────┐ │ HOW TO FOLLOW THE ARROW RULES │ │ │ │ DOWNWARD ARROW (↓) UPWARD ARROW (↑) │ │ 1. Follow arrow down to the first 1. Follow arrow up to the first │ │ row containing Ac and Re values. row containing Ac/Re values. │ │ 2. USE THE NEW SAMPLE SIZE associated 2. USE THE NEW SAMPLE SIZE │ │ with that row! associated with that row! │ │ │ │ EXAMPLE: Code Letter D (Size 8) at AQL 2.5: │ │ Table shows (↓). Follow down to Code E (Size 13) where Ac=0, Re=1. │ │ Auditor MUST inspect 13 pieces, NOT 8 pieces! │ └─────────────────────────────────────────────────────────────────────────────┘
6. Real Garment Case Study: Complete AQL Calculation
Let us examine a realistic apparel factory inspection scenario from start to finish.
Scenario Details
- Garment Style: Men’s 100% Cotton Piqué Polo Shirt
- Order PO Quantity: 8,400 pcs
- Packing: 24 pcs per master carton = 350 cartons
- Quality Specification: General Inspection Level II, Single Normal Sampling
- Quality Standard: Critical = AQL 0.0, Major = AQL 2.5, Minor = AQL 4.0
STEP-BY-STEP CALCULATION FLOW: 1. TOTAL LOT SIZE: 8,400 pcs └── Fits in Table 1 Range: "3,201 to 10,000" 2. GENERAL INSPECTION LEVEL II: └── Intersects at CODE LETTER "L" 3. TABLE 2-A FOR CODE LETTER "L": ├── Sample Size = 200 pcs ├── Critical (AQL 0.0) -> Ac = 0, Re = 1 ├── Major (AQL 2.5) -> Ac = 10, Re = 11 └── Minor (AQL 4.0) -> Ac = 14, Re = 15 4. CARTON SELECTION (Square Root Rule): └── Cartons to open = √(350) + 1 ≈ 18.7 + 1 = 20 cartons └── Pull 10 shirts randomly per carton (20 × 10 = 200 sample pcs)
Inspection Audit Results
| Defect Type | Description of Faults Found | Garments Affected | Threshold (Ac / Re) | Status |
|---|---|---|---|---|
| Critical | None found | 0 | Ac = 0, Re = 1 | PASS |
| Major | 2 broken collar points, 3 open placket seams, 2 out-of-spec sleeve cuffs, 1 dye stain | 8 | Ac = 10, Re = 11 | PASS (8 ≤ 10) |
| Minor | 6 uncut threads >1/2", 4 loose button threads, 3 slight care label tilts | 13 | Ac = 14, Re = 15 | PASS (13 ≤ 14) |
Final Decision: SHIPMENT ACCEPTED (PASSED AQL 2.5/4.0).
7. Factory Standard Operating Procedure (SOP): Conducting an AQL Audit
┌─────────────────────────────────────────────────────────────────────────────┐ │ FACTORY AQL INSPECTION WORKFLOW SOP │ │ │ │ [1. LOT COMPLETION CHECK] │ │ └── Verify 100% production completed & ≥80% packed in shipping cartons. │ │ │ │ [2. SAMPLING & CARTON SELECTION] │ │ └── Apply √(Total Cartons)+1 rule. Pull cartons across all pallet depths. │ │ │ │ [3. VISUAL & WORKMANSHIP AUDIT] │ │ └── Inspect 200 pcs under 1,000 lux D65 light using clock-wise method. │ │ │ │ [4. MEASUREMENT AUDIT] │ │ └── Measure key points on Special Level S-4 or 8-13 pcs across size set. │ │ │ │ [5. DATA TALLY & FORMAL DECISION] │ │ └── Compare Critical, Major, Minor totals against Ac/Re. Issue Report. │ └─────────────────────────────────────────────────────────────────────────────┘
- Lot Readiness Verification: Ensure 100% of garments are produced, finishing is complete, and at least 80% of master cartons are packed and sealed.
- Representative Sampling: Never allow factory staff to hand-pick cartons. The auditor must physically select cartons from top, middle, bottom, front, and back stacks.
- The Clockwise Inspection Technique: Inspect each garment methodically:
- Front view: Collar/neckline → Right shoulder → Armhole → Front chest/placket → Bottom hem.
- Back view: Back neck → Yoke → Back body → Side seams → Inside labels.
- Defect Tallying: Record each defective garment on the official inspection check sheet. Always photograph every Critical and Major defect alongside a measuring tape and PO label.
- Disposition & CAPA: If the lot fails, quarantine all cartons, initiate a 100% factory sorting/rework operation, and issue a Corrective and Preventive Action (CAPA) plan before scheduling re-inspection.
8. Summary & Key Takeaways
- AQL 2.5 / 4.0 is the universal benchmark governing apparel export inspections worldwide.
- Critical defects require zero tolerance (Ac = 0, Re = 1). A single broken needle or mold spore fails the entire batch.
- Single Sampling Mechanics: If defects ≤ Ac, the lot passes. If defects ≥ Re, the lot fails. Re is always Ac + 1.
- Garment-Level Evaluation: Always evaluate defective garments, not individual defect counts, against the sampling table thresholds.
- Master Table Navigation: Use ISO 2859-1 Table 1 to find the Code Letter under General Level II, then read sample size and Ac/Re limits from Table 2-A, strictly adhering to downward and upward arrow rules.
1. ISO 2859-1 (ANSI/ASQ Z1.4) Table 1: Sample Size Code Letters
| Lot Size (Garment Pcs) | Special Level S-1 | Special Level S-2 | Special Level S-3 | Special Level S-4 | General Level I | General Level II (Default) | General Level III |
|---|---|---|---|---|---|---|---|
| 2 to 8 | A | A | A | A | A | A | B |
| 9 to 15 | A | A | A | A | A | B | C |
| 16 to 25 | A | A | B | B | B | C | D |
| 26 to 50 | A | B | B | C | C | D | E |
| 51 to 90 | B | B | C | C | C | E | F |
| 91 to 150 | B | B | C | D | D | F | G |
| 151 to 280 | B | C | D | E | E | G | H |
| 281 to 500 | B | C | D | E | F | H | J |
| 501 to 1,200 | C | C | E | F | G | J | K |
| 1,201 to 3,200 | C | D | E | G | H | K | L |
| 3,201 to 10,000 | C | D | F | G | J | L | M |
| 10,001 to 35,000 | C | D | F | H | K | M | N |
| 35,001 to 150,000 | D | E | G | J | L | N | P |
| 150,001 to 500,000 | D | E | G | J | M | P | Q |
| 500,001 and over | D | E | H | K | N | Q | R |
2. ISO 2859-1 Table 2-A: Single Sampling Plans for Normal Inspection (Master Table)
| Code Letter | Sample Size (Pcs) | AQL 0.65 Ac / Re | AQL 1.0 Ac / Re | AQL 1.5 Ac / Re | AQL 2.5 (Major) Ac / Re | AQL 4.0 (Minor) Ac / Re | AQL 6.5 Ac / Re |
|---|---|---|---|---|---|---|---|
| A | 2 | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) |
| B | 3 | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) |
| C | 5 | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | 0 / 1 |
| D | 8 | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | 0 / 1 | 1 / 2 |
| E | 13 | ↓ (0 / 1) | ↓ (0 / 1) | ↓ (0 / 1) | 0 / 1 | 1 / 2 | 2 / 3 |
| F | 20 | ↓ (0 / 1) | ↓ (0 / 1) | 0 / 1 | 1 / 2 | 2 / 3 | 3 / 4 |
| G | 32 | ↓ (0 / 1) | 0 / 1 | 1 / 2 | 2 / 3 | 3 / 4 | 5 / 6 |
| H | 50 | 0 / 1 | 1 / 2 | 2 / 3 | 3 / 4 | 5 / 6 | 7 / 8 |
| J | 80 | 1 / 2 | 2 / 3 | 3 / 4 | 5 / 6 | 7 / 8 | 10 / 11 |
| K | 125 | 2 / 3 | 3 / 4 | 5 / 6 | 7 / 8 | 10 / 11 | 14 / 15 |
| L | 200 | 3 / 4 | 5 / 6 | 7 / 8 | 10 / 11 | 14 / 15 | 21 / 22 |
| M | 315 | 5 / 6 | 7 / 8 | 10 / 11 | 14 / 15 | 21 / 22 | ↑ (21 / 22) |
| N | 500 | 7 / 8 | 10 / 11 | 14 / 15 | 21 / 22 | ↑ (21 / 22) | ↑ (21 / 22) |
| P | 800 | 10 / 11 | 14 / 15 | 21 / 22 | ↑ (21 / 22) | ↑ (21 / 22) | ↑ (21 / 22) |
| Q | 1,250 | 14 / 15 | 21 / 22 | ↑ (21 / 22) | ↑ (21 / 22) | ↑ (21 / 22) | ↑ (21 / 22) |
| R | 2,000 | 21 / 22 | ↑ (21 / 22) | ↑ (21 / 22) | ↑ (21 / 22) | ↑ (21 / 22) | ↑ (21 / 22) |
3. Apparel Garment Defect Severity Matrix & Classification Standards
| Defect Category | AQL Standard | Accept / Reject Rule | Typical Garment Examples | Consumer / Commercial Impact |
|---|---|---|---|---|
| Critical Defect | 0.0 (or 0.10) | Ac = 0, Re = 1 (Zero Tolerance) | Broken needle fragment, sharp staple, loose metal snap, mold/mildew, blood stain, toxic chemical odor, non-compliant flammability. | Immediate product recall, safety hazard, severe legal liability, customs seizure. |
| Major Defect | 2.5 | Standard AQL 2.5 Table Limit | Open seam >1/4", hole or fabric ladder, missing button, wrong size label, critical out-of-tolerance measurement (e.g., chest ±1.5"), severe color shading across panels, broken zipper. | Product returned by consumer, unsellable at full retail price, garment fails functional use. |
| Minor Defect | 4.0 | Standard AQL 4.0 Table Limit | Uncut thread end >1/2" (non-safety), slight stitching run-off at non-visible hem, mild shade variation on inner facing, slightly crooked care label, minor press mark/shine. | Customer may notice but will not return the product; does not affect fit, durability, or primary aesthetics. |
Practical Commercial Flow
A factory QC team conducted a Final Random Inspection (FRI) on an export order of 5,000 pcs Men’s 5-Pocket Denim Jeans destined for a major European retailer under General Inspection Level II (Normal Single Sampling):
Factory Real-Life Scenario
Scenario: A knitwear manufacturer in Narayanganj produced 12,000 pcs of Graphic Hoodies for a US brand. During buyer PSI, the third-party auditor found 15 Major defective garments against an Ac of 14 (Re = 15) for Code Letter M (sample size 315 pcs). The shipment was placed on REJECT status.
Solution: The factory QA Director immediately instituted a 100% screening and rectification protocol across the entire 12,000-piece lot. The QA team identified that 8 of the 15 defective garments suffered from unclipped embroidery backing paper and broken coverstitch at the pocket hem. A dedicated 20-person rework station cleared all 12,000 garments over 36 hours.
Impact: On re-inspection under Tightened Inspection (Level II, Code M: Sample size 315, AQL 2.5 Tightened Ac = 10, Re = 11), the auditor found only 3 Major defects and 4 Minor defects. The lot passed re-inspection, averting a $45,000 air freight penalty.
Commercial Officer Best Practice
For multi-color and multi-size POs, draw samples proportionally across every SKU based on the packing list ratio (Square Root of Cartons Rule: √Total Cartons + 1). Ensure at least 1 garment is pulled from every selected carton to guarantee random representation.
Top Beginner Mistakes to Avoid
- Confusing AQL percentage with the maximum defect rate allowed in the total bulk shipment (AQL is a statistical sampling threshold, not a warranty of perfection).
- Summing multiple minor or major defects on a single garment as multiple defective units, artificially inflating the sample rejection tally.
- Failing to follow the arrow rules in ISO 2859-1 tables, which leads to using the wrong sample size when inspecting small or specialized lots.
- Allowing factory packaging lines to continue packing while sampling is underway, contaminating the lot size and sample validity.
- Overlooking Critical defects (e.g., broken needle fragments) under the assumption that a lot can pass if total Major defects are within limits.
- Selecting sample cartons only from the outer layer of pallet stacks, ignoring potential mold, moisture, or shading issues inside inner cartons.
Important Commercial & Trade Terminology (7 Terms)
The maximum percent nonconforming (or maximum number of defects per hundred units) that, for sampling inspection, can be considered satisfactory as a process average.
💡 Note: Standardized under ISO 2859-1, ANSI/ASQ Z1.4, and BS 6001.The highest number of nonconforming units or defects found in the sample that still permits the acceptance of the inspection lot.
💡 Note: If defects <= Ac, the lot passes.The lowest number of nonconforming units or defects found in the sample that requires the rejection of the inspection lot.
💡 Note: In single normal sampling, Re is always Ac + 1.An alphabetical letter (A through R) derived from the lot size and the chosen inspection level that dictates the number of units to be drawn for audit.
💡 Note: Determined via ISO 2859-1 Table 1.A garment unit containing one or more defects of a specified category (Critical, Major, or Minor).
💡 Note: Evaluated on a per-garment basis during AQL sampling calculations.The statistical probability of rejecting a lot that actually meets the required acceptable quality standard.
💡 Note: Typically designed at 5% (95% confidence level).The statistical probability of accepting a lot that actually has a defect level worse than the acceptable quality limit.
💡 Note: Reduced by increasing sample size (e.g., moving from Level I to Level III).Interview Preparation Questions & Answers (4 Questions)
Master these high-frequency interview questions for Commercial Officer, Merchandising, and Export Executive roles.
AQL 2.5 means that if the supplier’s continuous production process average stays at or below 2.5% defective garments, the vast majority of lots (typically 95% to 99%) will be accepted under ISO 2859-1 single normal sampling. It is NOT a promise that every carton contains zero defects or that the shipment contains exactly 2.5% defects; it is a statistical quality threshold that governs lot pass/fail decisions.
Frequently Asked Questions (3 FAQs)
Clear, beginner-friendly answers to the most common questions about the Commercial Department.
Key Takeaways & Summary Points
Executive Lesson Summary
AQL 2.5 sampling under ISO 2859-1 is the universally recognized statistical standard governing apparel quality control. By understanding sample size code letters, single sampling mechanics, accept/reject limits, and defect severity classification, garment QA professionals can objectively assess batch quality, mitigate commercial risk, and maintain strict compliance with international brand standards.
Lesson Downloads & SOP Templates
AQL 2.5 Sampling Calculator
Instant lot size, code letter, sample size, and Ac/Re threshold calculator.
Open Tool