Valid

GB/T 21664-2025Work sampling methods (English PDF)

工作抽样方法

Preview PDF

This is a limited preview

Buy now to download the full PDF (27 pages)

Need quotation for your management?

Get a formal quotation for GB/T 21664-2025 in 30 minutes.

Issued by

SAMR; SAC

Level / Type

National · Recommended

Issue date

December 31, 2025

Implementation date

April 1, 2026

Scope

GB/T 21664-2025 is the English-translated version of 工作抽样方法.

GB/T 21664-2025 is the Chinese standard "Work sampling methods". Its scope clause reads: This document describes the types of work sampling methods, work steps, work sampling implementation, and data analysis.

This document is applicable to research on time utilization and labor (work) efficiency, the compilation and revision of labor quotas, and the analysis and research of various time consumption methods.

Consumption, compile and relax time standards, and level the production line. Its clauses include terms and definitions.

Found what you need?

Document preview — GB/T 21664-2025

National Standard of the People's Republic of China

ICS: 03.100.30
Classification: A 02
Replacing: GB/T 21664-2008

Issued by: State Administration for Market Regulation; Standardization Administration of the PRC

Preface
1.Scope
2 Normative References
3.Terms and Definitions
4.Types of methods
4.1 On-site work sampling
4.2 Data Analysis Method
5.Work Steps
5.2 Determine the number of samples to be drawn
5.3 Sampling Methods
5.4 Determining the Observation Route
5.5 Develop a sampling form
6.Implementation of work sampling
6.1 Preliminary Observations
6.2 Actual Measurement
7.Organize and analyze 6.
7.1 Complete the summary table of results
7.2 Calculate the average event occurrence rate
7.3 Removing Outliers
7.4 Verification of Sampling Error
7.5 Data Summary and Analysis
Appendix A (Normative) Table 8.Number of N Values Corresponding to the Occurrence Rate Py
Appendix B (Informative) Case Study 12 of Statistical Calculation Methods
Appendix C (Informative) Random Number Table
Appendix D (Normative) Random Time Table for Determining Observation Times
Appendix E (Informative) Work Sampling Table
Appendix F (Informative) Formula for Calculating Relevant Time in Work Sampling Analysis
Appendix G (Informative) Work Sampling Methods and Analysis Examples

1 Scope

This document describes the types of work sampling methods, work steps, work sampling implementation, and data analysis.

Consumption, compile and relax time standards, and level the production line.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies.

This document.

GB/T 14002 Terminology for Labor Quotas and Staffing

3 Terms and Definitions

The terms and definitions defined in GB/T 14002 and the following terms and definitions apply to this document.

3.1 Worksampling

Using the principles of random sampling in statistics, and adhering to the principles of equal probability and independence of randomness, sampling is conducted on-site operators or machinery.

Instantaneous observation and recording are used to investigate the frequency and incidence of various operational events, using the necessary and smallest possible sample size to infer the nature of the observed object.

A method for analyzing the overall situation.

3.2 Simple random sampling

For a population of size N, a method is used to draw a sample of size n, where all possible samples have an equal probability of being selected.

[Source. GB/T 3358.2-2009, 1.3.4, with modifications]

3.3 systematic sampling

The population is divided into several balanced parts, and then, according to pre-defined rules, one individual is drawn from each part to obtain the required quantity.

Sample method.

[Source. GB/T 3358.2-2009, 1.3.12, with modifications]

3.4 Stratified sampling

A method for randomly selecting individuals from different strata (types) in a prescribed proportion from a population that can be divided into different strata (types).

[Source. GB/T 3358.2-2009, 1.3.6, with modifications]

3.5

The probability that the estimated value and the population parameter are within a certain allowable error range.

......
This preview omits tables, figures, formulas and parts of the technical clauses. The complete document — 27 pages — is available in the English PDF.

Referenced standards

Normative references

GB/T 14002Terminology of work and personnel quota

Editions of GB/T 21664

Edition	Title	Revision	Status
GB/T 21664-2025	Work sampling methods	current edition	Current
GB/T 21664-2008	Work sampling methods	previous edition	Superseded

This page sells the current edition, GB/T 21664-2025. Earlier editions are listed for reference only.

How to Download GB/T 21664-2025

1
Add to cart
Click "Download PDF" on this page and choose "Buy this standard". You can add more standards before checkout.
2
Checkout
Enter your email and billing details. Payment is processed securely by Stripe (cards or bank transfer). Prefer bank details? Request a quotation (min. order $300).
3
Instant delivery (0–9 sec)
Delivery is automatic: within seconds of payment you'll receive an email with a secure download link. The link stays valid for 72 hours.
4
Invoice included
A tax invoice is attached to the confirmation email. Need a custom invoice? Contact us.