Measuring Hearing Loss

Measuring hearing loss is frequently confusing and,recording of a list of words and then ask you to say
oftentimes, people get decibels and the concept of athem back. The audiologist then compares what you
percentage mixed up. Decibel is an open-ended scalethink you heard to what was actually spoken. The ratio
of loudness that begins with zero, which is defined asof correct words to the number of words spoken can
the faintest sound that can be heard by a human ear.be seen as the percentage of your discrimination. This
From there, regular conversation is usually around 60can be an important measurement, but it is not a way
decibels, most power tools fall somewhere betweenof gauging loss of hearing.
100 and 120 decibels, and a gunshot might measure atTherefore, the most accurate way of quantifying loss
150 decibels or more. For every 10 dB (decibels) theof hearing is to say someone has a certain decibel of
volume increases, the perceived loudness doubles andloss, which can be equated to general guidelines
there is a tenfold increase in sound intensity.describing the loss. For example, a 20-40 dB loss might
If someone, for example, had loss of hearing thatbe considered as "mild" hearing loss by an audiologist.
made it impossible for him or her to hear sound fainterAbove this level, but below 60 or 70 decibels might be
than 30 dB, you could say this person has a 30-decibelconsidered as "moderate" hearing loss. Levels above
loss. Likewise, if they have a 50-decibel loss, theythis can be considered "serious" or "severe" hearing
cannot hear sound that is less than 50 decibels. Asloss, with 90 to 100 dB or more of hearing loss being
you might guess, the greater the decibel loss, the less"profound" or "extreme" hearing loss. Again, these are
a person can hear. If someone has 40-decibel loss, thisjust guidelines, but they help in explaining the level of
person probably will not be able to hear you whisperhearing loss in a much more helpful way than
and may have some difficulty with even regularinaccurate and meaningless percentages.
volume speaking.Another way of putting this loss in perspective is to
Although 0 dB is the lowest volume a human ear canconsider what the effects of this kind of loss are on
hear, it should not be confused with the lowest volumean individual as well as what they might do to remedy
a human ear usually hears. According to mostthe situation. Those who can hear sounds at around
classifications, even people who cannot hear below 1520 dB or less have what could be considered "normal"
or 20 dB are considered to have "normal" hearing. Inhearing. Mild hearing loss usually means that, although
addition, since there is no highest number of decibels,the loss is not very extensive, one might have trouble
you cannot simply come up with a percentage forfollowing a conversation or distinguishing other sounds
hearing loss. The decibel scale is logarithmic, meaningwhen in a loud environment. Moderate hearing loss is
that an increase of 10 dB is a 10-fold increase and notmore severe than this, but usually less than 70 dB of
simply a set percentage. For example, 50 dB is 3000hearing loss. Those with this level of loss will have
times louder than 30 dB, not a 66 % increase as onetrouble listening to a conversation without a hearing aid
might assume.of some sort. More severe hearing loss means that an
The implications of this in measuring sound loss areindividual is very dependent on a hearing aid or implant
that you cannot say that someone with 20 dB ofin order to hear. Extreme hearing loss is what most
hearing loss has a 20% sound loss. On the other hand,would consider borderline deaf, at best. Those with this
you can use percentages to describe one's ability totype of loss depend on sign language, written text,
discriminate between sounds. If you have had or willcaptioned media, and lip reading. Some may benefit
ever have your hearing tested, the audiologist will askfrom an implant.
you to put on headphones. The will then play a