Overview
EN ISO 14978:2018 - Geometrical product specifications (GPS) - General concepts and requirements for GPS measuring equipment (ISO 14978:2018) is the CEN-adopted European version of ISO 14978:2018. It defines the general requirements, terms, calibration principles and characteristic types for GPS measuring equipment such as micrometers, calipers, gauge blocks and rotary axis form measuring instruments. The standard provides a common framework to improve communication between manufacturer/supplier and customer/user and to guide companies and standards developers when defining and selecting measurement equipment characteristics.
Key topics
- Scope and terms: Unified vocabulary and definitions used for GPS measuring equipment to ensure consistent interpretation across manufacturers, users and standards bodies.
- Design characteristics: Guidance on what design features should be specified for different classes of measuring instruments.
- Metrological characteristics: Identification, definition and selection of measurement-related attributes (e.g., resolution, temperature-related behaviour, geometry of contact elements).
- Specification & presentation: Rules for expressing metrological characteristics, including MPE (maximum permissible error) functions - constant, proportional and combined forms.
- Calibration and verification: Requirements and recommended approaches for calibration, verification methods and handling of measurement uncertainty when reporting instrument performance.
- Marking and documentation: Minimum marking and data-sheet content (Annex B) to support traceability and procurement.
- Annexes and supportive material: Practical annexes (A–E) covering minimum requirements for device-specific GPS standards, common design characteristics and test uncertainty.
Applications
EN ISO 14978:2018 is practical for:
- Manufacturers and suppliers specifying product declarations, data sheets and acceptance criteria for GPS measuring equipment.
- Purchasing and quality personnel who need to prepare clear, comparable specifications for procurement.
- Calibration laboratories and metrology professionals responsible for verifying and certifying measuring instruments and reporting uncertainty.
- Standards writers developing device-specific GPS standards (this document provides the basis and template guidance).
Typical use cases:
- Defining acceptance criteria for new micrometers or calipers.
- Preparing equipment data sheets for tendering and supplier evaluation.
- Structuring calibration programs and traceable verification of gauge blocks and coordinate devices.
Related standards
- ISO/TC 213 (Dimensional and geometrical product specifications and verification) - technical committee responsible for GPS standards.
- Normative references included in the standard (examples from the document): ISO/IEC Guide 99, ISO/IEC Guide 98-4, ISO 14253-5 - referenced for measurement concepts and uncertainty guidance.
Keywords: EN ISO 14978:2018, GPS measuring equipment, geometrical product specifications, calibration, metrological characteristics, design characteristics, micrometers, calipers, gauge blocks, measurement uncertainty.
