GB/T 2829-2025 Sampling procedures and tables for periodic inspection by attributes (Apply to inspection of process stability)
1 Scope
This document specifies single, double and quintic sampling plans and sampling procedures using the rejectable quality limit (expressed as percent nonconforming or as nonconformities per 100 items) as the quality index.
This document applies to the inspection by attributes of process stability by the producer. It establishes the lower limit of lot quality (rejectable quality limit) for a specific lot (within a specified period), in order to control product quality problems caused by systematic instability during the production process.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 3358.1 Statistics - Vocabulary and symbols - Part 1:General statistical terms and terms used in probability
GB/T 3358.2 Statistics - Vocabulary and symbols - Part 2 : Applied statistics
GB/T 19000 Quality management systems - Fundamentals and vocabulary
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 3358.1, GB/T 3358.2 and GB/T 19000 and the following apply.
3.1.1
item
object that can be individually described and considered
Example: A discrete article, a given quantity of bulk material, a service, an activity, a person, a system, or a combination thereof.
[Source: GB/T 3358.2‑2009, 1.2.11]
3.1.2
lot
definite quantity of a product, material or service collected together under certain conditions
Note: In this document, "lot" refers specifically to all unit products manufactured for production pattern inspection, or all unit products manufactured within a specified period during lot production after passing the production pattern inspection.
3.1.3
lot size
number of unit products in a lot
[Source: GB/T 2828.1-2012, 3.1.14]
3.1.4
sample unit
unit product taken from the lot for inspection
3.1.5
sample
subset of a population consisting of one or more sample units
[Source: GB/T 3358.2‑2009, 1.2.17, modified]
3.1.6
sample size
number of sample units in a sample
Note: In multi‑stage sampling, the sample size refers to the total number of sample units in the sample after the final stage of sampling.
[Source: GB/T 3358.2‑2009, 1.2.26, modified]
3.1.7
nonconformity
quality characteristic of a unit product does not conform to specified requirements
Note: Nonconformities are usually classified according to the importance of the quality characteristics of the unit product, or according to the severity of the nonconformity. They are generally classified as: class A nonconformity, class B nonconformity and class C nonconformity.
3.1.8
class A nonconformity
critical nonconforming
case that the very important quality characteristic of a unit product does not conform to specified requirements, or the quality characteristic of a unit product does not conform to a very severe degree
Note: In periodic inspection, a relatively small rejectable quality limit (RQL) is used for this class of nonconformity.
3.1.9
class B nonconformity
major nonconforming
case that important quality characteristic of a unit product does not conform to specified requirements, or the quality characteristic of a unit product does not conform to a severe degree
Note: In periodic inspection, a rejectable quality limit (RQL) larger than that for class A but smaller than that for class C is specified for this class of nonconformity.
3.1.10
class C nonconformity
minor nonconforming
case that the general quality characteristic of a unit product does not conform to specified requirements, or the quality characteristic of a unit product does not conform to a minor degree
Note: In periodic inspection, a rejectable quality limit (RQL) larger than those for both class A and class B may be used for this class of nonconformity.
3.1.11
nonconforming item
unit product that has one or more nonconformities
Note: Based on the type of nonconformity, they are generally classified as: class A nonconforming item, class B nonconforming item and class C nonconforming item. A class A nonconforming item has one or more class A nonconformities, and may also have class B and/or class C nonconformities; a class B nonconforming item has one or more class B nonconformities, and may also have class C nonconformities, but does not include class A nonconformities; a class C nonconforming item has one or more class C nonconformities, but does not include class A or class B nonconformities.
3.1.12
percent nonconforming (in a population or lot)
number of nonconforming items in a population or lot divided by the population size or lot size, multiplied by 100, i.e.:
Percent nonconforming = (number of nonconforming items in the population or lot / population size or lot size) × 100
[Source: GB/T 2828.1‑2012, 3.1.9, modified]
3.1.13
nonconformities per 100 items (in a population or lot)
number of nonconformities in a population or lot divided by the population size or lot size, multiplied by 100, i.e.:
Nonconformities per 100 items = (number of nonconformities in the population or lot / population size or lot size) × 100
[Source: GB/T 2828.1‑2012, 3.1.11, modified]
3.1.14
lot quality
quality of a single submitted lot (expressed as percent nonconforming or as nonconformities per 100 items).
3.1.15
rejectable quality level
lower limit of lot quality considered unacceptable in periodic inspection
3.1.16
inspection
activity of measuring, checking, testing one or more characteristics of a product or process and comparing them with specified requirements to determine conformity
3.1.17
inspection by attributes
inspection in which, for each unit product in the product set under consideration, the occurrence of one or more specified characteristics is recorded, and the number of unit products that have or do not have the characteristic is counted, or the number of times the above events occur on the product, the product set or the unit product of the opportunity space is counted
Note: When the inspection only records whether the unit product/item is nonconforming, it is called nonconforming item inspection. When the inspection counts the nonconformities on each unit, it is called nonconformity inspection.
[Source: GB/T 3358.2-2009, 4.1.3]
3.1.18
lot-by-lot inspection
inspection of each lot in a series of submitted lots
[Source: GB/T 3358.2-2009, 4.1.15]
3.1.19
periodic inspection
inspection carried out to determine whether the stability of the production process within a specified period (specified either by time or by the number of unit products manufactured) meets the specified requirements, by taking samples from one or more lots that have passed lot‑by‑lot inspection
3.1.20
production pattern inspection
periodic and lot‑by‑lot inspection carried out to determine whether a given production line is capable of batch manufacturing products that meet the specified quality requirements
3.1.21
batch production inspection
periodic and lot‑by‑lot inspection carried out to determine whether a production line, after passing the production pattern inspection, still be capable of batch manufacturing products that meet the specified quality requirements
3.1.22
acceptance number
maximum number of nonconformities or nonconforming items permitted in the samples of an accepting lot in count acceptance sampling inspection
3.1.23
rejection number
minimum number of nonconformities or nonconforming items in the sample of a rejecting lot in count acceptance sampling inspection
Contents
Foreword
1 Scope
2 Normative references
3 Terms, definitions and symbols
3.1 Terms and definitions
3.2 Symbols
4 Inspection procedures
5 Implementation of inspection
5.1 Requirements for inspection cycle
5.2 Selection of test items and composition of test groups
5.3 Provisions on test methods and quality characteristics
5.4 Classification of nonconformities
5.5 Provisions on rejectable quality limit (RQL)
5.6 Provisions on determinant levels
5.7 Selection of sampling plan type
5.8 Retrieval of sampling plan
5.8.1 General
5.8.2 Retrieval of single sampling plan
5.8.3 Retrieval of double sampling plan
5.8.4 Retrieval of quintic sampling plan
5.9 Sampling
5.10 Samples for inspection
5.11 Judgment of conformity or nonconformity for periodic inspection
5.11.1 Method for judging conformity or nonconformity for periodic inspection
5.11.2 Cases where lot quality is expressed in terms of percent nonconforming
5.11.3 Cases where lot quality is expressed in terms of nonconformities per 100 units
5.12 Disposition after periodic inspection
5.12.1 Relationship between periodic inspection and lot‑by‑lot inspection
5.12.2 Disposition after periodic inspection is passed
5.12.3 Disposition after periodic inspection is not passed
5.12.4 Disposition of sample units after periodic inspection
5.12.5 Special cases for carrying out periodic inspection
6 Operating characteristic curves and average sample size curves
6.1 Operating characteristic (OC) curves
6.2 Average sample size (ASN) curves
Annex A (Informative) Determination of rejectable quality limit (RQL)
Annex B (Informative) Calculation of average sample size of sampling plan
B.1 General
B.2 Average sample size for double sampling
B.3 Average sample size for quintic sampling
B.4 Average sample size curves
Bibliography
GB/T 2829-2025 Sampling procedures and tables for periodic inspection by attributes (Apply to inspection of process stability)
1 Scope
This document specifies single, double and quintic sampling plans and sampling procedures using the rejectable quality limit (expressed as percent nonconforming or as nonconformities per 100 items) as the quality index.
This document applies to the inspection by attributes of process stability by the producer. It establishes the lower limit of lot quality (rejectable quality limit) for a specific lot (within a specified period), in order to control product quality problems caused by systematic instability during the production process.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 3358.1 Statistics - Vocabulary and symbols - Part 1:General statistical terms and terms used in probability
GB/T 3358.2 Statistics - Vocabulary and symbols - Part 2 : Applied statistics
GB/T 19000 Quality management systems - Fundamentals and vocabulary
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 3358.1, GB/T 3358.2 and GB/T 19000 and the following apply.
3.1.1
item
object that can be individually described and considered
Example: A discrete article, a given quantity of bulk material, a service, an activity, a person, a system, or a combination thereof.
[Source: GB/T 3358.2‑2009, 1.2.11]
3.1.2
lot
definite quantity of a product, material or service collected together under certain conditions
Note: In this document, "lot" refers specifically to all unit products manufactured for production pattern inspection, or all unit products manufactured within a specified period during lot production after passing the production pattern inspection.
3.1.3
lot size
number of unit products in a lot
[Source: GB/T 2828.1-2012, 3.1.14]
3.1.4
sample unit
unit product taken from the lot for inspection
3.1.5
sample
subset of a population consisting of one or more sample units
[Source: GB/T 3358.2‑2009, 1.2.17, modified]
3.1.6
sample size
number of sample units in a sample
Note: In multi‑stage sampling, the sample size refers to the total number of sample units in the sample after the final stage of sampling.
[Source: GB/T 3358.2‑2009, 1.2.26, modified]
3.1.7
nonconformity
quality characteristic of a unit product does not conform to specified requirements
Note: Nonconformities are usually classified according to the importance of the quality characteristics of the unit product, or according to the severity of the nonconformity. They are generally classified as: class A nonconformity, class B nonconformity and class C nonconformity.
3.1.8
class A nonconformity
critical nonconforming
case that the very important quality characteristic of a unit product does not conform to specified requirements, or the quality characteristic of a unit product does not conform to a very severe degree
Note: In periodic inspection, a relatively small rejectable quality limit (RQL) is used for this class of nonconformity.
3.1.9
class B nonconformity
major nonconforming
case that important quality characteristic of a unit product does not conform to specified requirements, or the quality characteristic of a unit product does not conform to a severe degree
Note: In periodic inspection, a rejectable quality limit (RQL) larger than that for class A but smaller than that for class C is specified for this class of nonconformity.
3.1.10
class C nonconformity
minor nonconforming
case that the general quality characteristic of a unit product does not conform to specified requirements, or the quality characteristic of a unit product does not conform to a minor degree
Note: In periodic inspection, a rejectable quality limit (RQL) larger than those for both class A and class B may be used for this class of nonconformity.
3.1.11
nonconforming item
unit product that has one or more nonconformities
Note: Based on the type of nonconformity, they are generally classified as: class A nonconforming item, class B nonconforming item and class C nonconforming item. A class A nonconforming item has one or more class A nonconformities, and may also have class B and/or class C nonconformities; a class B nonconforming item has one or more class B nonconformities, and may also have class C nonconformities, but does not include class A nonconformities; a class C nonconforming item has one or more class C nonconformities, but does not include class A or class B nonconformities.
3.1.12
percent nonconforming (in a population or lot)
number of nonconforming items in a population or lot divided by the population size or lot size, multiplied by 100, i.e.:
Percent nonconforming = (number of nonconforming items in the population or lot / population size or lot size) × 100
[Source: GB/T 2828.1‑2012, 3.1.9, modified]
3.1.13
nonconformities per 100 items (in a population or lot)
number of nonconformities in a population or lot divided by the population size or lot size, multiplied by 100, i.e.:
Nonconformities per 100 items = (number of nonconformities in the population or lot / population size or lot size) × 100
[Source: GB/T 2828.1‑2012, 3.1.11, modified]
3.1.14
lot quality
quality of a single submitted lot (expressed as percent nonconforming or as nonconformities per 100 items).
3.1.15
rejectable quality level
lower limit of lot quality considered unacceptable in periodic inspection
3.1.16
inspection
activity of measuring, checking, testing one or more characteristics of a product or process and comparing them with specified requirements to determine conformity
3.1.17
inspection by attributes
inspection in which, for each unit product in the product set under consideration, the occurrence of one or more specified characteristics is recorded, and the number of unit products that have or do not have the characteristic is counted, or the number of times the above events occur on the product, the product set or the unit product of the opportunity space is counted
Note: When the inspection only records whether the unit product/item is nonconforming, it is called nonconforming item inspection. When the inspection counts the nonconformities on each unit, it is called nonconformity inspection.
[Source: GB/T 3358.2-2009, 4.1.3]
3.1.18
lot-by-lot inspection
inspection of each lot in a series of submitted lots
[Source: GB/T 3358.2-2009, 4.1.15]
3.1.19
periodic inspection
inspection carried out to determine whether the stability of the production process within a specified period (specified either by time or by the number of unit products manufactured) meets the specified requirements, by taking samples from one or more lots that have passed lot‑by‑lot inspection
3.1.20
production pattern inspection
periodic and lot‑by‑lot inspection carried out to determine whether a given production line is capable of batch manufacturing products that meet the specified quality requirements
3.1.21
batch production inspection
periodic and lot‑by‑lot inspection carried out to determine whether a production line, after passing the production pattern inspection, still be capable of batch manufacturing products that meet the specified quality requirements
3.1.22
acceptance number
maximum number of nonconformities or nonconforming items permitted in the samples of an accepting lot in count acceptance sampling inspection
3.1.23
rejection number
minimum number of nonconformities or nonconforming items in the sample of a rejecting lot in count acceptance sampling inspection
Contents of GB/T 2829-2025
Contents
Foreword
1 Scope
2 Normative references
3 Terms, definitions and symbols
3.1 Terms and definitions
3.2 Symbols
4 Inspection procedures
5 Implementation of inspection
5.1 Requirements for inspection cycle
5.2 Selection of test items and composition of test groups
5.3 Provisions on test methods and quality characteristics
5.4 Classification of nonconformities
5.5 Provisions on rejectable quality limit (RQL)
5.6 Provisions on determinant levels
5.7 Selection of sampling plan type
5.8 Retrieval of sampling plan
5.8.1 General
5.8.2 Retrieval of single sampling plan
5.8.3 Retrieval of double sampling plan
5.8.4 Retrieval of quintic sampling plan
5.9 Sampling
5.10 Samples for inspection
5.11 Judgment of conformity or nonconformity for periodic inspection
5.11.1 Method for judging conformity or nonconformity for periodic inspection
5.11.2 Cases where lot quality is expressed in terms of percent nonconforming
5.11.3 Cases where lot quality is expressed in terms of nonconformities per 100 units
5.12 Disposition after periodic inspection
5.12.1 Relationship between periodic inspection and lot‑by‑lot inspection
5.12.2 Disposition after periodic inspection is passed
5.12.3 Disposition after periodic inspection is not passed
5.12.4 Disposition of sample units after periodic inspection
5.12.5 Special cases for carrying out periodic inspection
6 Operating characteristic curves and average sample size curves
6.1 Operating characteristic (OC) curves
6.2 Average sample size (ASN) curves
Annex A (Informative) Determination of rejectable quality limit (RQL)
Annex B (Informative) Calculation of average sample size of sampling plan
B.1 General
B.2 Average sample size for double sampling
B.3 Average sample size for quintic sampling
B.4 Average sample size curves
Bibliography
