1.1 This practice describes a procedure for calibrating the electron binding-energy (BE) scale of an X-ray photoelectron spectrometer that is to be used for surface analysis with unmonochromated aluminum or magnesium K X-rays or monochromated aluminum K X rays.1.2 It is recommended that the BE scale be calibrated after the instrument is installed or modified in any substantive way. Also, it is recommended that the instrumental BE scale be checked, and if necessary, recalibrated at inte