ASME Y14.5
Notes About Y14.5

The Y14.5 standard is updated every 10 to 15 years.  The current version is ASME Y14.5-1994.  A new revision is now complete, and will be published in the second quarter of 2009.
The previous version of Y14.5 was ANSI Y14.5-1982.  The change from ANSI to ASME is because the American National Standards Institution (ANSI) have delegated responsibility for the standard to the American Society of Mechanical Engineers (ASME).  It is still the same standard.

The version of the standard many will be familiar with is Y14.5M.  This is simply the metric version of the standard.
ASME Y14.5.1-1994 is known as 'the Math Standard'. It contains the mathematical definitions and principles which underlie the Y14.5 system.
About ASME Y14.5
ASME Y14.5 is the American standard for Dimensioning and Tolerancing.  It defines the system known as Geometrical Dimensioning and Tolerancing (GD&T).  Although GD&T has become widely used as a generic description of Geometrical Tolerancing, strictly speaking, it is the name of the American system (GPS being the ISO equivalent).

The Y14.5 standard is used further afield than just the USA.  It is the standard in predominant use in South America and Canada, and is also used around the globe by companies which have American or Canadian ownership.


Iain Macleod Associates can provide ASME Y14.5 versions of our training courses in Geometrical Tolerancing and Tolerance Stack Analysis.

We can also provide conversion courses for companies who are changing over from the Y14.5 standard to the ISO system, or from the ISO system to Y14.5.