Overview
EN ISO 7499:2024 - Technical product documentation (TPD) - Unique integral feature identification (UIFI) is a CEN-endorsed ISO standard that defines a human-readable method to uniquely identify integral features of a part in technical product documentation. The standard specifies the use of an integral feature indicator: a graphical symbol (leader + reference line) combined with a unique alpha‑numerical label (integral feature identifier). It also sets rules for indicating repeated features and the proportions/dimensions of simplified graphical symbols used for enumeration.
Keywords: EN ISO 7499:2024, Unique integral feature identification, TPD, UIFI, integral feature identifier, alpha-numerical label, graphical symbols.
Key topics and requirements
- Scope: Unambiguous, human-readable identification of every integral feature on a part where needed to improve readability and traceability in TPD.
- Integral feature indicator: Combines a leader line, reference line and an alpha-numerical label that names the feature (UIFI).
- Label formats: Rules for single/repeated letters, prefixed/postfixed usage and enumerated labels for repeated features (to maintain unique identification).
- Graphical symbols: Definition of the indicator symbol and specification of proportions/dimensions for simplified symbols used when enumerating repeated features.
- Integration with specifications: Guidance on how UIFI appears together with tolerances, datum references and other specifications in drawings.
- Special cases: Handling of datum feature identifiers, portions of features, repeated and compound features.
- CAD and interoperability: Recognizes existing CAD internal identifiers are often unreadable; encourages harmonized, human-readable UIFI support in CAD systems.
Practical applications
- Improves clarity and traceability in engineering drawings, BOMs and nomenclature drawings.
- Facilitates clear verbal/written communication between designers, suppliers, manufacturers, metrologists and quality teams.
- Supports documentation-linked processes: SOPs, measurement plans and reports, nonconformity tracking, FMEA, tolerance stack-up and change requests.
- Simplifies specifying secondary operations (machining, surface treatments) or special requirements applied to specific features or groups of features.
- Aids inspection and verification by enabling direct reference to named features on drawings and in measurement reports.
Who should use this standard
- Mechanical designers and CAD modelers
- Technical product documentation (TPD) authors and draftsmen
- Quality, metrology and manufacturing engineers
- CAD vendors seeking standardized feature labeling
- Procurement and supplier engineers managing part specifications
Related standards
- ISO 5459 - Geometrical tolerancing - Datums and datum systems (used for datum feature identifiers)
- ISO 81714-1 - Design of graphical symbols for technical documentation
- ISO/TS 21619 - CAD and drawing usage contexts (referenced in the introduction)
EN ISO 7499:2024 brings consistent, human-readable feature identification into TPD workflows, improving communication, inspection and lifecycle traceability for parts and assemblies.
