What does 0 dB HL indicate?

0 dB HL, or 0 decibels Hearing Level, is used as a calibration reference for measuring hearing thresholds. It indicates the average threshold of hearing for a young adult with normal hearing. In audiometric testing, the 0 dB HL mark corresponds to the softest sounds that an average person with typical hearing can detect at specific frequencies.

By establishing this baseline, audiologists can assess an individual's hearing capability and determine if it falls within the normal range or if there are any hearing impairments. The concept of 0 dB HL is critical for understanding how hearing loss is quantified, as it provides a frame of reference for evaluating hearing sensitivity against what is considered normal.

This understanding is foundational in occupational hearing conservation, where distinguishing between different degrees of hearing loss and noise exposure is essential for preventing further complications in work environments with noise hazards.