Mainly the NDT standards have a general structure:
1. Scope
here is a short description about the intention of the standard and often also a hint about the safety when using X-Rays (it is the user's responsibility).
2. Referenced Documents
Here is a list of standards which are using in the actual ASTM standard. It use to start with ASTM Standards and sometime foreign Standards follow.
3. Terminology
In the beginning of this chapter you will find a link to E1316
(3.1 Definitions relating to the radiographic examination, which appear in Terminology E1316, shall apply to the terms used in this practice.)
followed by definitions of terms specific to the actual standard, which have local meanings and could differ to similar terms in other standards.
4. Significance and Use
The name is the program - sometimes a little short sometime a longer description. If you open a standard and the scope is not sufficient to see, if the standard is what you were looking for, read chapter 4.

The following chapters may differ and depend on the type of standard.

Only the last chapter is by default named:
Keywords
and here you will find the buzzwords with are relevant for the actual standard.

_________________
Best Regards
Klaus