This Practice provides general requirements for the design, materials, fabrication, examination, inspection, testing, certification, and pressure relief of three classes of small pressure vessels and heat exchangers as defined by size and Maximum Allowable Working Pressure (MAWP) in Table 1a or 1b of this Practice.

This Practice is applicable to:
a. The standard, pre-designed pressure vessels and heat exchangers supplied as part of pre-engineered package units (e.g., refrigeration and air-compressor systems)
b. “Off-the-shelf” vessels and exchangers
c. Vessels (e.g., filters) or exchangers built from the manufacturer’s standard parts

For purposes of this Practice, the term “vessel” includes heat exchangers.

This Practice is not intended for the following:
a. Vessel in “Lethal Service” as defined in Section VIII, Division 1 of the ASME Boiler and Pressure Vessel Code (Code)
b. Vessels for which design wall thickness is governed by loadings from wind pressure or earthquake forces