This Standard establishes methods for determining the influence of installation conditions or flow patterns on the performance of flowmeters in closed conduits (i.e., pipe, ducts, etc.). This Standard also addresses: (a) means and terminology for defining a reference condition for flow calibration of a particular flowmeter; and (b) guidelines for extrapolation and interpolation of installation effects to untested piping conditions. This Standard does not supersede or otherwise replace qualification tests or installation tests that are specified by other standards such as ISO 9951.