Calibration Frequently Asked Questions (FAQ)

Question: What is an audiometer?
Answer: An audiometer is an instrument which measures what a person hears in response to a pure-tone or pulse-tone stimulus at a specific frequency (pitch) measured in Hertz (Hz) and at a specific intensity (loudness) measured in Decibels (dB)

Question: What is a Tympanometer?
Answer: A Tympanometer is an instrument which is an objective test of middle-ear function in response to a sound and pressure stimulus to measure the mobility of the tympanic membrane, the middle ear pressure, and the volume of the external ear canal

Question: What is an OAE?
Answer: An Otoacoustic Emissions (OAE) is an instrument which determines the functionality of the tympanic membrane, middle ear, and the cochlea through the measurement of an inaudible sound echo emitted by the cochlea in response to an audible sound stimulus

Question Where can I purchase an audiometer, tympanometer, OAE or other such equipment:?
Answer: There are numerous vendors/companies who sell and/or service this type of equipment in Minnesota. Some of the vendors we have posted on this site sell as well as service this equipment and you may contact any of them for more information regarding the purchase of instruments. They all are reputable vendors. The other option would be to contact the manufacturer of the particular instrument you wish to buy or simply “Google” your inquiry and take it from there. We do not specifically endorse or recommend any particular seller of this type of equipment.

Question: Do I have to have my audiometer, tympanometer, and/or Otoacoustic Emissions (OAE) machines calibrated every year, even if they are not used very often?
Answer: When you bring your machines into the regional sites for “calibrations” your machines are being checked to see if they are still operating within specific specifications. If not, the machine in question needs to be calibrated to those specifications so that it accurately measures what it is designed to measure. It is recommended by the manufacturers, by U.S. Occupational Safety & Health Administration (OSHA), the National Institutes of Health (NIH) and by the Minnesota Department of Health (MDH) that machines be checked annually to ensure the accuracy of the machine’s readings.

Question: What causes audiometers, tympanometers, and/or OAEs to get out of specification and need to be re-calibrated?
Answer: There are multiple potential reasons why an instrument may get out-of- specification and require re-calibration and/or repair. Some of the possibilities are related to: exposures to extreme temperatures, the age of the machine, how often it is used, and proper handling and storage.

Question: Where do I bring my instruments to be checked for proper calibration?
Answer: Go to the MDH website and type “audiometer calibrations” into the search bar or click on Calibration Locations and Dates. The sites are organized regionally and regions are listed with the counties they serve in the spreadsheet. You are not required to use a specific site, so you may choose to use a site that is most convenient for you.

Question: Why is no date or vendor listed for the site I have chosen?
Answer: MDH lists the sites and gives that information to each vendor who has agreed to be part of this process. The vendors contact each site where they will offer their services and determine the date, time, and other directions with the specific site. The vendors contact MDH to give them that information and we post it for your convenience.

Question: Do I contact the site or the vendor and how do I know which vendor will be used for a specific site?
Answer: As soon as we have the information we will post it. However, you may always contact the vendor of your choice and obtain the information from them. Check under the General Instructions link to get a listing of all the vendors and their contact and pricing information.