This document illustrates the ambiguity caused by the use of dimensional specifications to control properties other than linear or angular size and the benefit of using geometrical specifications instead.

Dimensional tolerancing can be indicated by ± tolerancing or geometrical specifications.

The ambiguity caused by using ± tolerances for dimensions other than linear or angular sizes (for individual tolerances and general tolerances according to, e.g. ISO 2768-1 and ISO 8062-3) is explained in Annex A.

NOTE 1 The figures, as shown in this document, merely illustrate the text and are not intended to reflect actual usage. The figures are consequently simplified to indicate only the relevant principles.

NOTE 2 For indications of dimensional specifications, see the following:

— ISO 14405-1 for linear size;

— ISO 14405-3 for angular size;

— ISO 2538-1 and ISO 2538-2 for wedges;

— ISO 3040 for cones.

NOTE 3 The rules for geometrical specifications are given in ISO 1101.