Chapter 7, authored by Thomas J. Ahl for the first Edition, and co-authored by Marcus N. Bressler for the second Edition, provides commentary on Section III, Subsections NC and ND. This commentary addresses pressure vessels, atmospheric tanks, and 0–15 psig tanks as presented in the ASME B&PV Code, Section III, Division 1, Subsection NC, Class 2 Components and Subsection ND, Class 3 Components. This chapter does not address piping, pumps, and valves; these are addressed in Chapters XX for Class 2 and Class 3 Piping, and in Chapter 13 for Nuclear Pumps and Valves. The chapter discusses, in order, each...