Remenber that ASME III have 8 subsetcions you are asking for these three:
Class 1 Components (III, Subsection NB)Those components that are part of the primary core cooling systemComponents (III, Subsection NH)Those components that are used in elevated temperature service
Class 2 Components (III, Subsection NC)Those components that are part of variousimportant-to-safety emergency core cooling systems
Class 3 Components (III, Subsection ND)Those components that are part of thevarious systems needed for plant operation