Overview - ISO 128-3:2022 (Technical product documentation - Views, sections and cuts)
ISO 128-3:2022 defines the general principles for presenting views, sections and cuts in technical product documentation (TPD). It applies to a wide range of technical drawings - mechanical, electrical, architectural and civil engineering - and aligns with orthographic projection methods specified in ISO 5456-2. The standard also addresses reproduction requirements (including microcopying per ISO 6428) and provides field-specific rules in annexes for mechanical, building and construction drawings.
Key topics and technical requirements
- Selection of views: Use the most informative view as the principal view; limit the number of views to the minimum necessary to avoid ambiguity and unnecessary repetition.
- Projection methods: Principles for first‑angle and third‑angle orthographic projection are referenced and symbolized according to ISO conventions.
- Identification of views: Each view (except the principal/front view) is marked with a capital letter near a reference arrow; placement and orientation rules ensure consistent readability.
- Cuts and sections: Definitions for “cut” and “section” and rules for indicating cutting planes, identifying sections and referencing sectioned views.
- Partial and simplified views: Rules for partial views (to highlight features) and simplified representation of symmetrical parts to save space and clarify drawings.
- Graphical conventions: Hatching/section lining, shading/toning, thin sections, and treatment of adjacent sections and specific materials are covered (see Clause 7).
- Reproduction considerations: Guidance for drawing elements to remain legible when reproduced or microcopied, per ISO 6428.
- Annexed guidance: Normative and informative annexes supply graphical symbols (A), historical practices (B), and application rules for mechanical (C/D), building (E) and construction drawings (F).
Practical applications and intended users
ISO 128-3:2022 is used to ensure clear, unambiguous presentation of 2D views, sectional views and cuts across technical documentation workflows. Typical users:
- Mechanical, electrical and civil engineers
- CAD/BIM designers and drafters
- Technical illustrators and documentation specialists
- Architects and construction professionals
- Quality, manufacturing and assembly teams relying on consistent drawings
Benefits include improved cross-disciplinary communication, fewer manufacturing or construction errors, and consistent documentation for legal, procurement and regulatory use.
Related standards
Keywords: ISO 128-3:2022, technical product documentation, views sections cuts, orthographic projection, first-angle, third-angle, engineering drawings, TPD, CAD documentation.