ASTM standards are typically called out by their ASTM number and year of revision, for example F1554-07. Occasionally, when small revisions are made at ASTM that do not necessitate a full year revision, the year is annotated with a letter. We fielded a chat recently where this question came up. Below is the correspondence and answer.
7:37:04 AM: Robert:
What does the designation “ae1” after ASTM F1554 mean?
7:41:08 AM: Dane McKinnon:
Hi Robert. It has to do with revisions. Major revisions are noted as a new revision year i.e. -03 (2003) or -07 (2007). Minor revisions are designated as “a” and editorial (typo) revisions get the epsilon “e”. So -07ae1 is the 07 revision with one minor revision and one editorial change.
7:42:42 AM: Robert:
Thanks! Do you have any idea what the minor revision might have been?
7:44:04 AM: Dane McKinnon:
Let me go look at an older book. Give me one second.
7:47:18 AM: Dane McKinnon:
It looks like the minor change was switching the hot-dip galvanizing reference from A153 to F2329 and changing the mechanical galvanizing class of B695 from class 50 to class 55.
7:50:11 AM: Robert:
OK Thanks again. I tried to google ae1 and various other things but had no luck.
7:50:44 AM: Dane McKinnon:
You are welcome. We are happy to help.