Speech Perception in a
Noisy Environment (tm)
Many people have normal or near-normal hearing when given a standard hearing
screening test in a clinical setting. However, when they are required to
understand or perceive words or sentences in a setting with background noise,
they function poorly. According to the World Health Organization, "Even slight
hearing impairments in the high-frequency sound range may cause problems with
speech perception in a noisy environment."
Most commonly these problems are noticeable in Customer Service Personnel, Security
Monitors, Professionals who must use radio communications, Pilots, Command and Control
Operators, or any employees whose job it is to listen and understand.
In many jobs, it is critical that the listener be able to understand speech over
some level of background noise. Also, the Americans With Disabilities Act requires
"reasonable accommodation" for physical impairments. You need to be able to identify
which employees have this job-related problem. Then, you need to be able to decide
which employees can be accommodated either with special amplification or with Listening
Hence, we designed, and in 1994 had developed for us by one of the premier medical schools
in the U.S., a two-part test that can be administered in 15 minutes. The first part
asks the subject to repeat single syllable words that are presented at incrementally
changing signal-to-noise ratios over background "multi-talker babble (noise)". The second
part is similar, but presents short sentences to be repeated.
The result of the test for each subject is a set of two signal-to-noise ratios, for
single syllable words and short sentences respectively, as measured in decibels, that
are the thresholds for speech perception by the subject. These are plotted for each
subject on an individual Speech Perception Ability Chart (tm) where they are compared
to both national norms and your organization's norms.
The test is very easy to administer. The Integrity Center provides you with the
test CD, on loan, and you play that for your subjects in a normal office environment using
an approved CD player and an approved headset. At the same time that your Test Monitor
is administering the
test, the Test Monitor is checking-off on an Internet web page those words that are
correctly repeated by the subject. At the conclusion of the test, the Test Monitor
clicks the SHOW TEST RESULTS button, and another web page immediately appears with a print
interface containing the graphical report of the subject's test. The Test Monitor
prints that page, signs it, and enters it in the subject's file.
For those organizations wanting to collect the test data for their HR database, we have
provided an API protocol for their IT personnel to use so that they can collect the
records over the Internet from The Integrity Center's data center.