  The radioactive isomer $^{83\mathrm{m}}$Kr has many properties that make it
very useful for various applications. Its low energy decay products, like
conversion, shake-off and Auger electrons as well as X- and $\gamma$-rays are
used for calibration purposes in neutrino mass experiments and direct dark
matter detection experiments. Thanks to the short half-life of 1.83 h and the
decay to the ground state $^{83}$Kr, one does not risk contamination of any
low-background experiment with long- lived radionuclides. In this paper, we
present two new applications of $^{83\mathrm{m}}$Kr. It can be used as a
radioactive tracer in noble gases to characterize the particle flow inside of
gas routing systems. A method of doping $^{83\mathrm{m}}$Kr into xenon gas and
its detection, using special custom-made detectors, based on a photomultiplier
tube, is described. This technique has been used to determine the circulation
speed of gas particles inside of a gas purification system for xenon.
Furthermore, 83m Kr can be used to rapidly estimate separation performance of a
distillation system.
