Overview
EN ISO 128-3:2022 - Technical product documentation (TPD) Part 3: Views, sections and cuts defines the general principles for presenting views, sections and cuts in technical drawings. Published by CEN as the European adoption of ISO 128-3:2022, it updates and supersedes earlier editions (EN ISO 128-3:2020 and related parts). The standard applies to a wide range of technical product documentation (mechanical, electrical, architectural, civil engineering) and follows orthographic projection methods described in ISO 5456-2. It also addresses reproduction requirements (including microcopying per ISO 6428) and provides field-specific guidance in annexes.
Key topics
The standard establishes consistent conventions and graphical rules for clear, unambiguous representation of parts and assemblies:
- Choice and arrangement of views (front, top, side, partial and simplified views)
- Projection methods: first-angle and third-angle projection, with graphical symbols and guidance
- Cuts and sections: identification of cutting planes, reference indicators, local and revolved sections
- Hatching and area representation on sections: rules for cross-hatching, shading/toning, thin sections and adjacent sections
- Line conventions: extra-wide outlines and how to depict thin or concealed features
- Reference indication for views and enlarged features, including labelling and detail callouts
- Special cases: symmetrical parts, enlarged features, and field-specific practices (see annexes)
- Reproduction considerations, including microcopying constraints and legibility
Applications and who uses it
EN ISO 128-3:2022 is essential for professionals who produce, interpret or maintain technical drawings and TPD:
- Mechanical engineers, product designers and manufacturing drafters
- Architects, civil and structural engineers producing construction drawings
- CAD/BIM technicians implementing orthographic views and sectioning rules
- Technical illustrators, QA and document control teams ensuring drawing consistency
- Standards coordinators and trainers implementing company drawing standards
Practical uses include preparing manufacturing and assembly drawings, construction plans, installation instructions and cross-discipline documentation where consistent representation of views, sections and cuts ensures accurate communication across suppliers, contractors and regulators.
Related standards
- ISO 5456-2 - Orthographic projection methods (first-angle, third-angle)
- ISO 128-15 - Views and sections specific to shipbuilding drawings
- ISO 16792 - Views and sections for 3D CAD models
- ISO 6428 - Reproduction (microcopying) requirements
Adopting EN ISO 128-3:2022 improves interoperability, reduces misinterpretation in drawings, and supports standardized CAD/TPD workflows across industries.
