Hearing Screening Audiometer Use, Care and Calibration

The Audiometer

MDH recommended audiometers have test tones ranging from 250 to 8000 Hz and volumes of 0-80/100 decibels. Headphones are calibrated to a specific audiometer and are not interchangeable with other machines.

MDH does not recommend speech stimuli screening equipment such as Verbal Auditory Screening for Children (VASC), where a word is presented to the child, and the child has to identify a related picture. 

General Care

• Handle gently and avoid dropping.
• Avoid extreme temperatures (below freezing and above 90º F).
• Keep cords free of tangles and twists.
• Keep the case closed to prevent dust build-up

Infection Control

• Clean headphones before each re-use with a cleaning agent or alcohol-free wipes.
• Do not use alcohol because it may dry out the rubber cushions on headphones.
• Keep all moisture away from the diaphragm (the hole in the center of the headphones).

In the event of a lice outbreak, the (American Academy of Audiology, 2011) recommends modifying screening schedules.

For more information on Audiometers, General Care, or Infection Control, refer to the Hearing Screening Manual (PDF).

Audiometer Mechanical Function Check

Audiometer Mechanical Function Check (PDF) form.

Calibration

Annual calibration of hearing screening equipment is recommended by the U.S. Occupational Health and Safety Administration (OSHA), the National Institutes of Health (NIH) and the Minnesota Department of Health. Different factors such as age of the machine, frequency of use, exposure to extreme temperatures, and handling and storage of the machine can cause the instruments to become non-compliant to specifications set forth by the American National Standard Specification for Audiometers (ANSI). Annual calibration ensures the accuracy of the machine's readings.

Audiometers should have yearly calibrations. Extensive calibrations are typically done at a repair facility or factory about every fifth year.

The Audiometer Needs Repair If:

• Tone does not sound normal, static is heard, or sound is not produced when tone lever/button is pressed.
• Headphones do not remain in proper position over ears.
• A dial or switch does not function, or indicator lights do not glow.

Calibration Vendor List

Audiometer Supplies and Repair

For a detailed list of Audiometer Repair or Purchase locations, refer to the Hearing Screening Manual (PDF) on page 38.

Biologic Calibration Check

Optional unless performing threshold audiometry.

Used to ensure that the audiometer is ready for accurate screening. Refer to the Biological Calibration Check Form (PDF)

When to do:

• Prior to threshold screening. 
• When there is reason to suspect the audiometer may not be working properly.