GD&T "CZ" (Common Zone)

[[Ke...]]

It has been a few years since I have had GD&T training: did ASME adopt the ISO standard "CZ" (Common Zone) notation... or do I need to have a discussion with our drafters, checkers & approvers?

[[Ri...]]

I believe the ISO spec uses CZ to express simultaneous evaluation when typically referring to a pattern of features. In ASME, it is implied to be a CZ unless SEPARATE REQUIREMENT is invoked.

[[Ke...]]

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So... the "CZ" notation has *not* been formally adapted by ASME...

Now my question is:
Is there a better to note a "Common Zone" on an ASME print, without creating a Frankensteins Monster print...
In this case we are looking at a flatness evaluation. In the past notes have been added, such as "Hatched Areas" (shown), or added a notation such as "Two Surfaces evaluated as one"

My concern is that is that if notations are "borrowed" from ISO, then we will start having prints that use a hodgepodge of notations from each standard that may not lend itself to the best/correct interpretation.

[[Ri...]]

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I have one customer who had something similar where Datum A was based (4) locations of hatched area. They opted to have Detail Views that showed the (4) locations, and each location defined a Datum Target area. Then they just had a Flatness of Datum A shown in a different view.

Maybe you could do something similar?

[[Ke...]]

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100%
This also, I think, for non datum surfaces
https://www.gdandtbasics.com/continuous-feature