The standards can be purchased directly from ASTM as an individual PDF download or via a subscription service (ASTM Compass).
Specification A240/A240M, which references A480/A480M, is specifically designed for pressure vessel applications requiring certified materials. astm a480 a480m pdf
ASTM A480/A480M is a standard specification for general requirements for flat-rolled stainless and heat-resisting steel plate, sheet, and strip. Here's an informative text on the topic: The standards can be purchased directly from ASTM
The standard explicitly warns against combining values from inch-pound and SI units, as they are not exact equivalents and doing so may result in nonconformance. which references A480/A480M