Business · Records and learning

Product specification · original probability model

Does an AQL field guarantee a defect-free lot?

Compare Hartalega’s AQL field with NIST sampling definitions, then calculate an explicitly fictional acceptance probability without inventing a lot guarantee.

Original documentary or teaching figure for Does an AQL field guarantee a defect-free lot?. Toy plan is not Hartalega’s plan, a calibrated AQL 1.5 plan, a standard or regulatory recommendation. No actual lot defect rate, zero-defect warranty or medical-performance finding. Finite-lot sampling without replacement requires different inputs/model.
1.5
AQL field on the selected product page
20 / 1
Fictional sample size / acceptance number
94.01% / 39.17%
Model acceptance probabilities at p = 0.02 / 0.10

The short answer

What can a reader infer from Hartalega’s stated AQL 1.5, and why is acceptance under a sampling plan different from proving every item in a lot is conforming?

Compare the evidence

A field, a method and a supported conclusion

Retain the object, assumptions and scope behind each statement.

Original comparison of inspected records and explicitly fictional teaching examples.
Record or exampleWhat it suppliesWhat it does not establish
Manufacturer’s product tableA stated AQL field and product attributes.Actual shipment defect rate or a complete sampling procedure.
NIST method recordsDecision rules, quality levels and acceptance risks.The manufacturer’s undisclosed n/c settings.
Fictional modeln = 20, c = 1 and two assumed probabilities.Observed quality, compliance or medical efficacy of real gloves.

Chronology

A timeline of the turning points

  1. AQL field

    Retain the specification and the absence of a particular lot test.

  2. Single versus other sampling plans

    NIST defines the decision structure and its risk terms.

  3. Explicit model

    Independent binomial assumptions are teaching inputs, not a manufacturer’s procedure.

Begin with the field actually published

Hartalega’s COATS product page places AQL 1.5 alongside fields such as examination type and non-sterile status. This is a manufacturer’s product specification. The selected table does not give a particular shipment’s test results, the sample size, acceptance number or a certificate for an identified production lot. It also does not make a claim that every glove in a shipment has been individually tested.

The number should therefore remain a labelled specification field. It is not an observed defect percentage for a lot that the reader has inspected. Nor does the AQL field independently establish clinical performance, suitability for a particular procedure or the truth of every medical statement elsewhere in the marketing page. This guide examines sampling language, not a choice of protective equipment.

Sources for this section: [1]

A sampling plan needs a decision rule

NIST describes a single-sample plan using two values: n, the number sampled, and c, the largest number of nonconforming items that can be observed before rejecting the lot. In that form, reject when the sample contains more than c nonconforming items. Double and sequential plans use different decision structures, so their sample counts cannot be silently substituted for a single plan.

NIST describes AQL as a baseline quality level at which the producer wants a high probability of acceptance. It separately identifies a worse quality level of concern to the consumer and the risk of accepting at that level. Acceptance is consequently a decision made under uncertainty. A high chance of accepting good production is not a guarantee that an accepted lot contains no nonconforming items.

Sources for this section: [2] · [3]

Choose and label a probability model

For an original teaching model, suppose twenty independent items are sampled and acceptance allows at most one nonconforming item. Let p be the stipulated probability that each sampled item is nonconforming. Under an independent binomial model, acceptance occurs with zero or one such item: P(accept) = (1 − p)^20 + 20p(1 − p)^19.

This is a fictional n = 20, c = 1 plan. It is not identified as Hartalega’s plan, an ISO plan or a regulated glove-inspection procedure, and it is not calibrated to the product’s AQL 1.5. For sampling without replacement from a finite lot, the lot size and composition matter; a hypergeometric model may be appropriate. Independence is a supplied assumption here, not a fact established about a real shipment.

Sources for this section: [2] · [3]

Exercise and worked probabilities

Evaluate the fictional plan at p = 0.02 and p = 0.10. At 0.02, the two terms sum to approximately 0.940101, so about 94.01% of samples would lead to acceptance under repeated use of this model. At 0.10, the sum is approximately 0.391747, or 39.17%. Keep the assumed item probability and the probability of an acceptance decision in different columns.

Now assess the sentence “The sample was accepted, therefore the lot has zero nonconforming items.” It does not follow. The plan explicitly accepts a sample with one nonconforming item, and an accepted sample does not reveal every unsampled item. Even a zero count in the sample would not prove zero in the lot. The probabilities describe a model’s repeated decisions, not an independently measured Hartalega defect rate.

Sources for this section: [2] · [3]

What further record would answer a shipment question?

To investigate a particular lot, request its identity, applicable test and standard, sampling type, sample size, acceptance criterion and actual observations. Any subsequent inference also depends on whether the sampling and test conditions justify the chosen statistical model. The manufacturer’s product field alone does not provide those records.

The comparison gives a useful division of labour between sources. The product page supplies the stated specification. NIST supplies definitions and decision structures. The original exercise supplies explicit mathematical assumptions. Keeping those three layers visible prevents a specification number from becoming an invented shipment statistic, a zero-defect warranty or a medical-performance conclusion.

Sources for this section: [1] · [2] · [3]

Continue the chronology

Biography context

Explore Malaysia through connected lives

Connected biographies

People connected with these records

MalaysiaBusiness

Career from 1969

Kuan Kam Hon

Hartalega founder and manufacturing organiserKuan Kam Hon moved from family construction work into manufacturing, founding Hartalega and helping organise its development in examination gloves.Read biography

Quick answers

Common questions

Is AQL 1.5 the observed defect rate of a shipment?
The inspected product table does not establish that. A stated AQL and an observed lot defect rate are different kinds of information.
Are the exercise’s twenty samples a recommended inspection plan?
No. This is an explicitly fictional independent-binomial model, not a manufacturer, ISO or regulatory plan.

Primary and institutional sources

How this history was checked

Selected institutional, technical and participant records support the comparison. Fictional examples retain their stated assumptions and do not substitute for actual operating or compliance evidence. This article was reviewed on 29 October 2026.

  1. HartalegaCOATS: selected product specification fields
  2. NISTSingle Sample Acceptance Plan: Dataplot reference
  3. NIST/SEMATECH Engineering Statistics HandbookWhat kinds of Lot Acceptance Sampling Plans are there?