TS EN ISO 3098-5

TS EN ISO 3098-5 addresses the general rules for lettering used in computer-aided preparation of technical product documentation, particularly technical drawings, when Latin alphabet characters are involved. Its focus is on consistent use of letters, numerals and marks in a CAD environment, aligned with the other parts of the ISO 3098 series, so the main concern is not the content of the text but its disciplined presentation in technical documents.

The role of CAD lettering in technical product documentation

In technical drawings, lettering is part of the information system: it carries dimensions, notes, part identifiers, symbols and explanatory text. Keeping the appearance of Latin letters and numbers consistent across drawings helps human readability and supports uniform output across different software and plotting environments. This standard is best understood as part of that broader lettering framework, used together with the other sections of the series.

How to understand the scope of this part

• It covers the general requirements for lettering in computer-prepared technical documents.
• It is intended especially for technical product documentation such as technical drawings.
• It addresses the use of Latin alphabet letters, numerals and marks in harmony with the related parts of the series.
• It should be read as part of the overall ISO 3098 lettering system rather than as a standalone writing guide.

In general CAD practice, lettering is managed together with font choice, proportion, placement and drawing scale. The aim is technical clarity rather than visual decoration: a consistent lettering system reduces the risk of misreading in production, inspection, maintenance and document exchange. Viewed that way, TS EN ISO 3098-5 helps define lettering as a functional element of technical communication, not merely a graphical one.