ISO 28598-1:2017

Overview

ISO 28598-1:2017 provides guidelines for acceptance sampling organized around the allocation of priorities principle (APP). It defines organizational principles for sampling inspection where successive inspections may be carried out by different parties (supplier, customer and/or third party). The standard applies to inspection of populations of discrete items delivered in lots and supports contractual or legislative arrangements that specify quality levels and lot acceptability criteria.

Key benefits called out in the standard:

• Supports use of prior information (objective and subjective) to select sampling plans
• Enables different parties to use sampling plans matched to their resources and risk tolerance
• Reduces the likelihood of contradictory inspection results and dispute escalation
• Can progressively reduce sample sizes as trust in the supplier’s quality increases

Key topics and requirements

ISO 28598-1:2017 covers the organizational and methodological aspects (guidance, not specific numeric plans). Major technical topics include:

• Terms, definitions and symbols used in APP-based sampling
• Quality measures and the role of information in quality assurance
• Selection of sampling systems for continuing series of lots or separate lots
• Requirements for lot quality and relationships between supplier, customer and third party
• Inspection objectives for each party (supplier, customer, third party)
• System requirements: reproducibility, flexibility, accommodation of party capabilities, cost efficiency
• Prior information types and economic aspects of using prior data or trust levels
• Choosing sampling plans and schemes, constraints on risks (type I / type II), and decision rules
• Re-submission procedures for lots previously not accepted
• Informative annexes: APP explanation and recommendations on setting customer’s risk

Note: Single-sampling APP plans by attributes are provided in ISO 28598-2; development of variable-sampling plans (ISO 28598-3) is under consideration.

Practical applications and users

ISO 28598-1 is useful where contractual or regulatory frameworks require inspection by multiple parties or where parties wish to formalize inspection governance:

• Quality managers and production supervisors designing inspection strategies
• Procurement and supplier quality engineers setting contractual acceptance criteria
• Third-party certifiers and auditors coordinating inspection outcomes with suppliers/customers
• Contract drafters and legal teams who want APP principles referenced in contracts and arbitration clauses
• Statisticians and inspection planners integrating prior information and trust metrics into sampling design

Practical use cases include supplier final inspection, incoming inspection, certification-related checks, dispute resolution frameworks, and progressive sampling regimes tied to demonstrated supplier performance.

Related standards

• ISO 28598-2:2017 - coordinated single sampling plans by attributes (APP plans)
• ISO 9001 / ISO 9004 - quality management systems that can provide prior information used by APP-based sampling

Keywords: ISO 28598-1, acceptance sampling, allocation of priorities principle, APP, supplier inspection, customer inspection, third-party inspection, sampling plans, lot inspection, sampling by attributes.