This document specifies methods for measuring the volume flow rate, base pressure, water vapour tolerance, power consumption, and the lowest start-up temperature of positive displacement vacuum pumps, which discharge gas against atmospheric pressure and with a usual base pressure <10 kPa.

In this document, it is necessary to use the determinations of volume flow rate and base pressure specified in ISO 21360‑1.

This document also applies to the testing of other types of pumps which can discharge gas against atmospheric pressure, e.g. drag pumps.