There is no single accepted method for revision sequencing, with different industries having different needs. Let’s collect those here.
Alpha
A common, simple system is alpha-lettering (A, B, C…). ASME gives some guidance on allowable letters to avoid ambiguities 1:
- Up to three alpha characters e.g. AAB.
- Avoid I,O,Q,S,X, andZ.
Footnotes
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ASME Y14.35-2014 paragraph 5.2. ↩