This day-long short course is intended for those who wish to understand the operation and use of residual gas analyzers and helium-based leak detectors. The class will be divided into several sections, beginning with background concepts needed to understand their operation; that will be followed by a description of the rga instrument; analyzing its spectra; how materials, components, and gauge location affect its results; a description of leak detectors; instrument sampling techniques, and some suggestions for their use in problem solving.