This part of ISO 10303 specifies the interpretation of the generic resources in order to satisfy the following requirements:

• for the description of a three dimensional shape by means of a boundary representation model with planar faces and implicit straight line edges;
• for the composition of one or more such shapes as a faceted_brep_shape_representation.

The following are within the scope of this part of ISO 10303:

• 3D geometry;
• B-reps;
• B-rep models;
• faceted B-reps;
• polyloops;
• unbounded geometry;
• use of topology to bound geometric entities;
• geometric transformations.

The following are outside the scope of this part of ISO 10303:

• 2D geometry;
• curves;
• explicit edge definitions;
• surfaces other than planes;
• offset curves and surfaces.