ISO 25178-73:2019

Overview

ISO 25178-73:2019 - Geometrical product specifications (GPS) - Surface texture: Areal - Part 73 provides a standardized vocabulary and classification for geometrical surface defects on material measures and calibration specimens. The standard defines what constitutes a defect on a measurement standard’s surface, categorizes defects by geometrical shape, and specifies terminology for possible ways to respond to detected defects. It is a normative reference for users who need unambiguous rules when purchasing, using or calibrating areal surface texture material measures.

Key topics

• Scope and purpose: Applies to material measures and calibration specimens conforming to ISO 5436‑1 and ISO 25178‑70 and aims to reduce ambiguity in handling surface defects.
• Defect definition: A defect is a portion of a measurement standard’s surface whose geometry deviates from the nominal (ideal) feature beyond an agreed or characteristic amount.
• Classes of geometrical defects: Terms are organized by geometrical shape, including upward/outward defects, downward/inward defects, neutral defects, and a special case (negative defects) related to replication methods.
• Responses to defects: The standard defines a set of response options (for example remove, avoid, repair), and explains that at least one response policy must be selected; some responses can coexist. This supports consistent decision‑making and traceability.
• Normative vocabulary: Definitions in the document are normative for GPS use and intended to be referenced by other surface‑texture standards and procedures.

Applications

• Specification and procurement: Helps customers and buyers specify nominal geometrical features and acceptable defect treatment when ordering material measures from manufacturers or suppliers.
• Calibration and conformity: Enables calibration laboratories and customers to agree on consistent policies for treating defects during calibration, improving reproducibility and traceability.
• Measurement uncertainty management: Assists users in formulating rules to treat defects that minimize measurement uncertainty (useful for compliance with ISO/IEC 17025:2017 requirements).
• Training and documentation: Educates metrologists, quality managers and technicians about the significance of different defect types and the appropriate handling strategies.
• Standards integration: Used by other GPS standards when selecting measurement locations or specifying areas to avoid on a specimen.

Who should use it

• Calibration laboratories and metrologists
• Manufacturers and suppliers of material measures and calibration specimens
• Quality and metrology engineers working with areal surface texture instruments
• Standards authors referencing defect treatment or measurement area selection

Related standards

• ISO 5436-1 (calibration specimen formats and use)
• ISO 25178-70 (material measures for areal surface texture)
• ISO/IEC 17025:2017 (laboratory competence and calibration policy)
• Other parts of the ISO 25178 areal surface texture series

Keywords: ISO 25178-73:2019, surface texture areal, GPS, material measures, calibration specimens, surface defects, measurement uncertainty, ISO 5436-1, ISO 25178-70, calibration laboratories.