The adverse effects that do not involve the hearing organs are linked to octave or one-third octave band levels exceeding which threshold across frequencies from 1 Hz to 40 kHz?

The adverse effects that do not involve the hearing organs are linked to octave or one-third octave band levels exceeding which threshold across frequencies from 1 Hz to 40 kHz?

• A. 150 dB
• B. 145 dB
• C. 155 dB
• D. 140 dB

Answer: (B)

Non-auditory adverse effects from noise arise when there is an enormous amount of energy spread across the entire spectrum, not just when the ears begin to hear. If octave-band or one-third octave-band levels across the full range from 1 Hz to 40 kHz rise above a certain level, the body’s non-hearing systems—such as the vestibular apparatus, autonomic nervous system, and vascular responses—can be stressed or triggered. That spectral threshold sits at about 145 dB. At or above this level across the whole frequency range, the combined energy is sufficient to provoke these non-auditory effects, even if the individual bands aren’t causing traditional hearing damage. Values lower than this (like 140 dB) don’t reach the criterion for non-auditory effects, while higher values (150 or 155 dB) exceed the standard threshold.

Non-auditory adverse effects from noise arise when there is an enormous amount of energy spread across the entire spectrum, not just when the ears begin to hear. If octave-band or one-third octave-band levels across the full range from 1 Hz to 40 kHz rise above a certain level, the body’s non-hearing systems—such as the vestibular apparatus, autonomic nervous system, and vascular responses—can be stressed or triggered.

That spectral threshold sits at about 145 dB. At or above this level across the whole frequency range, the combined energy is sufficient to provoke these non-auditory effects, even if the individual bands aren’t causing traditional hearing damage. Values lower than this (like 140 dB) don’t reach the criterion for non-auditory effects, while higher values (150 or 155 dB) exceed the standard threshold.