6.30 ears not covered. Listening situation where one or both ears are not covered with an earphone in a supra-aural cushion.
Annotation An example of a situation where both ears are not covered would be for determining hearing threshold levels for acoustic stimuli. An example where only one ear is not covered would be for determining pure-tone bone-conduction hearing threshold levels when a bone vibrator is placed on the mastoid of one ear and an earphone is placed on the other ear for the purpose of masking. See C11.21 and 4.42.« Back to Standards Terminolgy Index