ASI might be
AS1. AS1 refers to the clarity of the glass. #1 is used for windshields. It's interesting that we see this on almost every windshield, but a Google search shows no single, clear explanation of it's meaning. Many references to it being the lower limit on the windshield for tinting, but I don't find any 'official' explanation of that. Searching for American Standard turns up the bathroom fixtures company.
ASI and AS1 seem to be used, according to
this document, AS1 is the proper marking for glass that meets specific testing. (pg 23) Pg 24 says the line above the AS1 mark is the limit of tinting. Note: This is only a draft document.
AS is the mark from the American National Standards Institute
ANSI-American National Standards Institute