Our company has always used as revision scheme that follows ASME Y14.35M.

I'm struggling with trying to reproduce this in EPDM.

In EPDM it seems revision components are either Numeric or Alphabetical, so how can I get a rev "-"?

We do follow the convention on skipping letters, and the best way I've found to do this is creating a workflow with conditional transitions to increment the rev by 2 when one of these letters is the next rev.  Is there any better way to do this?

The rules we follow are:

Our first release is revision "-".

The first revision to a released document is "A".

We skip letters "I", "O", "Q", "S", "X", "Z".

After rev "Y" the next rev is "AA" then "AB", "AC", etc.

EDIT:  I've attached an excel file in a post below which has all the revisions from "-" to "YYY" following the rules above. This can be copied/pasted directly into the list box in EPDM. 

Message was edited by: Steve Soeder