IEC 60645-7:2009 applies to instruments designed for the measurement of auditory evoked potentials from the inner ear, the auditory nerve and the brainstem, evoked by acoustic and/or vibratory stimuli of short duration. IEC 60645-7:2009 defines the characteristics to be specified by the manufacturer, specifies performance requirements for two types of instrument, screening and diagnostic, and specifies the functions to be provided on these types. The purpose of IEC 60645-7:2009 is to ensure that measurements made under comparable test conditions with different instruments complying with this standard will be consistent. IEC 60645-7:2009 is not intended to r