This document specifies methods for the measurement of pumping characteristics of non-evaporable getters (NEGs). It is applicable to all sizes and all types of NEGs, including those:

—    with the shape of pill, disk, ring, strip, module, cartridge;

—    with pump structures;

—    and NEG coatings on inner surface of pipes and vacuum chamber.

A significant difference of pumping characteristics of the NEG and other vacuum pumps is that the pumping speed of the NEG depends on the sorption quantity. Furthermore, especially in the case of NEG coating, the sticking probability rather than the pumping speed is often the index of the pumping performance. Therefore, this document specifies the methods for measuring the pumping speed, the sorption quantity, and the sticking probability of NEGs.

WARNING    It is assumed that the user is familiar with the handling of combustible gases and poisonous ones and with ultra-high vacuum technology.