In a hearing clinic, we may measure hearing using something called audiometry. The woman pictured here is having an audiometry test done. She's wearing over the ear headphones. Or sometimes we may often use insert earphones. Those are like earbuds that you might get with an iPad or purchasing your smartphone. The woman fitting the headphones is the audiologist.
The audiologist plays a series of tones and those tones will range in pitch from low to high. They'll also be played at various volumes. The goal is to figure out how well the person can hear across that range of pitches, and across that range of volumes. So how quiet can it be for a given pitch that a person can hear?
We visualize the results of that test using something called an audiogram. (see below)
So you can see at the very top that represents the sounds that are really quite quiet so something like whispering or rustling leaves and then down towards the bottom of the audiogram is where sounds that are very loud. So things like a ambulance siren, or a jackhammer. Pictured here in blue is the area of the audiogram that is really important for speech.
So if someone is having trouble hearing within that range that means that they may have trouble understanding speech, particularly if it's in a noisy environment.
The chart starts with low tones, mid range tones through to higher frequencies
O Red - Right Ear
X Blue - Left Ear
These show the minimum amount of volime it takes to hear a sound.
Note when buying a hearing aid it is always better to get the audogram from your audiologist. They prefer to use their own calibrated equipment.