Futher to what Ed says...
Years ago I ran across this quick criterium from an engineering company. Using nominal inches and degrees Fahrenheit, if OD*T is greater than 1500, then analyze. If not, don't.
Why would this work? OD indicates stiffness and T indicates strain. That's k & x. Multiply those to get F (as in F=kx). A simple rule, and, as Ed says, "All the world is a Spring".
Looking at your chart I see a similar trend (for "Class II"): 4 inch at 150C (300F) and 6 inch at 100C (200F) gives OD*T of 1200 (instead of my 1500).
There is no "standard". And there are many other criteria indicating the need for analysis.