Why can't I wear my hearing aids during audiometry testing?

Occupational Safety and Health (OSHA) guidelines require initial and annual hearing checks of employees who are exposed to hearing hazards, such as high noise, in the workplace. These tests are used to monitor an employee's hearing acuity and sharpness over time by comparing an initial baseline audiogram to annual audiogram results. If a comparison of the results indicates a hearing loss, then the employer must take further action to investigate and mitigate the causes.

For audiometry testing, an employee will be asked to remove his or her hearing device for several reasons. First, for accurate comparisons to be made between tests, the testing method employed must be consistent. The best way to obtain this consistency is to perform a test of the employee's unassisted hearing ability. If an active hearing aid is in place during testing, it will amplify the sound emitted by the audiometric equipment. This amplification may be inconsistent from year to year or sound to sound. Second, earphones used for audiometric testing must fit snugly against the test subject's ears. Hearing aids, jewelry, or other items may interfere with the fit of the audiometric testing earphones and thus invalidate the results. Finally, if the hearing aid is turned off but remains in the employee's ear during testing, it may cause interference feedback.

OSHA requires that hearing impaired employees participate in an employer's hearing conservation program portion of health screenings to protect such workers from further damage or loss of any residual hearing ability. Thus, even an employee who is already equipped with a hearing aid must still have a baseline audiogram and annual audiometric tests if his or her workplace environment includes hearing hazards. Before asking an employee wearing hearing aids to remove the devices for testing, the test operator should communicate all verbal instructions for the test. The operator should also attempt to limit the number of times a test subject must remove and reinsert his or her hearing aids during the process.