Hearing Health Guide
Definition
The pure-tone average (PTA) is a composite measure derived from audiometric testing that represents the average hearing threshold across the key speech frequencies, conventionally 500 Hz, 1,000 Hz, and 2,000 Hz. It is reported in decibels hearing level (dB HL) and provides a standardized way to classify the degree of hearing loss. The American Academy of Audiology uses PTA as the primary index for hearing loss classification.
The audiologist measures the threshold (the softest tone audible) at each frequency during a hearing test. The thresholds at 500 Hz, 1,000 Hz, and 2,000 Hz are added together and divided by three. Some calculations include 4,000 Hz as well, particularly for assessing noise-induced damage.
The result is reported per ear. A PTA of 20 dB means the average of your thresholds at those three frequencies is 20 dB, within the normal range. A PTA of 55 dB indicates moderate hearing loss.
Normal hearing: 0-25 dB PTA. You can detect quiet sounds across the speech range without difficulty.
Mild hearing loss: 26-40 dB PTA. You may struggle in noise or miss soft speech. Many people at this stage are unaware of their loss.
Moderate hearing loss: 41-55 dB PTA. Conversational speech at normal volume is often missed. Hearing aids typically provide significant benefit.
Moderately severe: 56-70 dB PTA. Most conversational speech is missed without amplification. Hearing aids are strongly recommended.
Severe: 71-90 dB PTA. Even loud speech may be inaudible. Powerful hearing aids or cochlear implants are typically indicated.
Profound: 91+ dB PTA. Very little usable hearing across the speech range without cochlear implants or tactile aids.
PTA captures average threshold sensitivity but does not measure speech understanding, high-frequency hearing, or the ability to separate speech from background noise. Two people with the same PTA can have very different functional hearing. One may handle noise reasonably well while the other struggles significantly.
High-frequency hearing loss (3,000-8,000 Hz) is often missed or underweighted in a traditional three-frequency PTA. This matters because consonant discrimination (essential for speech clarity) depends heavily on frequencies above 2,000 Hz.
Common Questions