Hearing Reference Charts

The dense, citable tables this site exists for. What every decibel level sounds like, the hearing loss categories by threshold in decibels hearing level, what an audiogram actually plots and how to read one, typical hearing ranges by age band, hearing aid battery sizes and colours, dome and receiver sizing, wax guard intervals, and the NIOSH permissible noise exposure times.

6 pages in this section.

Sound levels

• Decibel Levels of Everyday Sounds A chart of A-weighted decibel levels for 32 everyday sounds, from a whisper to a firecracker, with the NIOSH exposure time for every level at or above 85 dBA.

Batteries

• Hearing Aid Battery Sizes The four standard zinc-air hearing aid battery sizes: colour, IEC designation, dimensions, typical life and which devices commonly use each one.

Hearing by age

• Hearing Frequency Range by Age The population tendency for the upper limit of audible frequency to fall with age, by age band, marked as a tendency and not a test anyone can take here.

Hearing levels

• Hearing Loss Levels in Decibels Both hearing loss scales side by side: US clinical categories and WHO 2021 grades, which set different boundaries and can disagree by a full category.

Audiograms

• How to Read an Audiogram The axes, symbols and speech banana on a standard audiogram, explained with the conventions used in every clinic, plus the pure tone average calculation.

Noise exposure

• NIOSH Noise Exposure Limits The full NIOSH permissible exposure ladder from 85 to 130 dBA, with the OSHA permissible time at every step, since the two published standards are not the same.

Not medical advice, not a hearing test, not a diagnosis. Everything in this section is general information compiled from published standards, regulatory classifications, manufacturer specifications and the consensus of verified owner reviews. The charts explain what a measurement shows. They cannot tell you what your hearing is, and nothing on this site can measure it. Only a licensed audiologist or physician can evaluate hearing. If hearing changed suddenly, affects one ear only, or comes with pain, drainage, dizziness or ringing alongside weakness or numbness, contact a doctor promptly rather than reading a chart.