Clinical audiometry samples hearing in octave-spaced tones from 125 Hz to 8 kHz

Evidence

Pure-tone audiometry is used to test a subject’s hearing threshold at specific frequencies approximately covering the speech hearing range (see Figure 2.10). These frequencies are spaced in octaves as follows: 125 Hz, 250 Hz, 500 Hz, 1 kHz, 2 kHz, 4 kHz and 8 kHz. The range of sound levels that are tested usually start 10 dB below the average threshold of hearing, and they can rise to 120 dB above it; recall that the average threshold of hearing varies with frequency (see Figure 2.10). — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2338

Categorization

• DEFINE: Supplies the concrete frequency grid and test-level range that define the standard hearing test protocol.