BS EN ISO 1660:2017

What is this standard about?

This is an engineering drawing standard about profile tolerancing – a subset of geometrical tolerancing, as covered in the companion standard BS EN ISO 1101. Both these international standards are part of the BS 8888 family on technical product documentation and specification.

Who is this standard for?

It will typically be used in the aerospace, defence, automotive, rail and nuclear sectors but is equally applicable to any engineering or manufacturing organization needing to produce engineering drawings in 2D or 3D. Users will be:

• Mechanical engineers
• Design engineers
• Manufacturing engineers
• Engineering designers
• Design agencies

 Why should you use this standard?

This version is the first update since 1987. It brings all profile tolerancing specification requirements up to date and accompanies BS EN ISO 1101 with the aim of helping design engineers to specify their products more accurately and unambiguously.

What’s changed since the last update?

The document has been completely overhauled to bring it up to date. Specifically:

• The requirements for defining the theoretically exact feature (the nominal geometry) have been made more explicit
• The definition of what constitutes the toleranced feature has been clarified and updated to follow the feature principle
• Tools for defining specifications for restricted features and compound features have been added
• The document now reflects the huge number of related standards published since its last edition in 1987