Monday, March 16, 2009

Specifications For Audiometric Booths

A proper testing environment is important for achieving accurate hearing test results.


Audiologists use audiometric booths to create a controlled setting in which to accurately test a patient's hearing. Although an audiologist working in a quiet doctor's office might be able to test someone's hearing effectively without a sound booth, an office near a consistent noise source will require a booth to ensure accurate testing.


The Occupational Safety and Health Administration (OSHA) sets the specifications that an audiometric sound booth must meet in order to filter out background noise effectively, thereby creating a good testing environment.


Sound Pressure Level Requirements


According to OSHA, the primary specification for an audiometric sound booth is that it sufficiently reduces ambient noise to ensure effective testing. The noise level in the booth measured in terms of sound pressure level must be below specific levels at a range of frequencies. To meet specifications, ambient noise at 500 and 1,000 hertz (Hz) must be below 40 decibels, at 2,000 Hz it must be below 47 decibels, at 4,000 Hz it must be below 57 decibels and at 5,000 Hz it must be below 62 decibels.


Testing Equipment


To ensure sound pressure levels within an audiometric testing booth meet specifications, they must be measured with equipment that meets certain standards. Measurement equipment must meet American National Standards Institute (ANSI) standards for sound level meters and for octave, half-octave and third-octave band filtering.


Test Frequency


The ambient sound pressure level within an audiometric sound booth depends on more than just the booth's construction. It also depends on the surrounding environment. For example, some businesses use mobile audiometric testing units. In such a case, the sound booth is located inside a van, and the sound pressure levels should be tested each time the van moves to a new location. In another example, some large stores such as Costco have audiometric sound booths on site. These should be tested periodically throughout the day because environmental noise levels may vary.







Tags: must below, sound booth, audiometric sound, below decibels, must below decibels