ISO/IEC 30134-2:2016
a) defines the power usage effectiveness (PUE) of a data centre,
b) introduces PUE measurement categories,
c) describes the relationship of this KPI to a data centre's infrastructure, information technology equipment and information technology operations,
d) defines the measurement, the calculation and the reporting of the parameter,
e) provides information on the correct interpretation of the PUE.
PUE derivatives are described in Annex D.