National foreword

This British Standard reproduces verbatim ISO 129‑1:2004 and implements it as the UK national standard. It supersedes BS ISO 129:1985 which is withdrawn.

The UK participation in its preparation was entrusted to Technical Committee TDW/4, Technical product specification, methodology, presentation and verification, which has the responsibility to:

aid enquirers to understand the text;
present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed;
monitor related international and European developments and promulgate them in the UK.

A list of organizations represented on this committee can be obtained on request to its secretary.

Cross-references

The British Standards which implement international publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.

This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.

Compliance with a British Standard does not of itself confer immunity from legal obligations.

This British Standard was published under the authority of the Standards Policy and Strategy Committee on 25 November 2004

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.

ISO 129‑1 was prepared by Technical Committee ISO/TC 10, Technical product documentation, Subcommittee SC 1, Basic conventions.

This part of ISO 129, together with ISO 129‑2, cancels and replaces ISO 129:1985 and ISO 406:1987 of which it constitutes a technical revision.

ISO 129 consists of the following parts, under the general title Technical drawings — Indication of dimensions and tolerances:

Part 1: General principles
Part 2: Mechanical engineering

1 Scope

This part of ISO 129 establishes the general principles of dimensioning applicable for all types of technical drawings.

NOTE The figures in this part of ISO 129 merely illustrate the text and are not intended to reflect actual usage. Consequently, they have been simplified to indicate only the relevant general principles applicable in any technical area.

Additional and more specific rules and details about the use of dimensioning for construction engineering are given in ISO 6284. For mechanical engineering, they will be given in the future ISO 129‑2.

2 Normative references

3 Terms and definitions

3.1 Features

3.2 Lines of dimensioning

3.3 Dimensions

3.4 Arrangement of dimensions

4 Principles of dimensioning and of indication of tolerances

4.1 General principles

4.2 Positioning of dimensions

4.3 Units of dimensions

5 Elements of dimensioning

5.1 General

5.2 Dimension line

5.3 Terminators and origin indication

5.4 Extension line

5.5 Leader line

5.6 Dimensional values (basic dimensions)

5.7 Letters representing dimensions

5.8 Tabular dimensioning

6 Elements of indication of tolerances

6.1 General rules

6.2 Limit deviations

6.3 Limits of dimensions

7 Indications of special dimensions

7.1 Arrangement of graphical and letter symbols with dimensional values

7.2 Diameters

7.3 Radii

7.4 Spheres

7.5 Arcs, chords and angles

7.6 Squares

7.7 Equally spaced and repeated features

7.8 Symmetrical parts

7.9 Indication of levels

7.10 Dimensions of out-of-scale represented features

7.11 Auxiliary dimensions

8 Arrangements of dimensions

8.1 General

8.2 Parallel dimensioning

8.3 Running dimensioning

8.4 Chain dimensioning

8.5 Coordinate dimensioning

8.6 Combined dimensioning

Bibliography

BS ISO 129-1:2004

Technical drawings. Indication of dimensions and tolerances - General principles

Published:

25 Nov 2004

Withdrawn:

1 Mar 2018