The two axes
Frequency, or pitch, runs across the top from 250 Hz on the left to 8000 Hz on the right. Low pitches sit on the left, high pitches on the right. Intensity, or loudness, runs down the side from -10 dB at the top to 120 dB at the bottom. The lower a mark sits on the page, the louder that pitch had to be before you heard it.
Each mark is the softest sound you detected at that pitch. O usually means the right ear by air conduction, X the left ear, and the bracket symbols show bone conduction, which tests the inner ear directly.
What the numbers mean
Hearing thresholds are grouped into broad bands that describe the difficulty, not the person.
- 0 to 25 dB: normal hearing range for adults
- 26 to 40 dB: mild loss, soft speech and group conversation become difficult
- 41 to 55 dB: moderate loss, ordinary conversation is often missed
- 56 to 70 dB: moderately severe, speech must be loud to be followed
- 71 to 90 dB: severe, most everyday speech is inaudible without amplification
- Above 90 dB: profound, and usually a candidate for high-power devices or implant referral
Air, bone and the gap between them
When bone conduction is normal but air conduction is poorer, the gap between them points to a conductive problem in the outer or middle ear: wax, fluid, a perforation or an ossicular issue. Many of these are medically or surgically treatable, which is why the gap matters more than the raw numbers.
When air and bone thresholds sit together and both are reduced, the loss is sensorineural, arising in the cochlea or the hearing nerve. That type is managed with hearing aids, rehabilitation and, where indicated, onward referral rather than medication.
The shape tells the story
A line that slopes downwards to the right is the classic pattern of age-related and noise-related loss, and explains the familiar complaint of hearing speech without understanding it. A dip around 4000 Hz suggests noise exposure. A flat line across all frequencies often accompanies middle-ear disease, and a rising line points to certain inner-ear conditions.
Speech testing is reported alongside the graph. Two people with identical audiograms can differ widely in how well they discriminate words, and that score is what predicts how much benefit a hearing aid will give.
Bring your audiogram with you
An audiogram from anywhere in the country can be reviewed at the centre and compared with a fresh test. Patients travel to us from across the Coast, Nairobi and upcountry, and a copy of any previous result makes that first appointment considerably more useful.