What Is Audiometry Testing?

Audiometry testing is the medical term for a hearing test or screening. A certain level of hearing loss is expected with age. According to one study, one-quarter of people age 50 or older experience some degree of diminishment. More severe cases, however, often indicate a serious health condition and can lead to quality-of-life issues for the individuals affected. It is common for school-age children to have their hearing evaluated but adults are sometimes tested as well. Audiometry testing is a diagnostic tool for any person suspected of hearing loss, or who spends a significant amount of time in a work or other environment with elevated noise levels.

Hearing is a precious gift that needs to be protected. If you have questions or concerns about your hearing, contact your Baptist Health primary care physician who can guide you in the right direction.

Who Takes Hearing Tests? Why Are They Required?

Anyone with evidence of a hearing problem, or who wants to establish a baseline for future comparisons, can benefit from audiometric testing. This is especially true for persons working in noisy environments, such as factories or on construction sites. The Occupational Safety and Health Administration (OSHA) requires that businesses in which employees are exposed to noise levels an average of 85 decibels (dBs) or more over an eight-hour workday offer a hearing-conservation program, which includes both baseline and annual audiometric testing. (Decibels are a measure of sound volume. A human whisper registers about 20 dB; a rock or rap concert up to 120 dB; and a jet engine as much as 180 dB.)

Audiometric testing is also useful in diagnosing hearing loss that results from:

• Autoimmune diseases affecting the inner ear
• Birth defects
• Chronic infections
• Physical injury
• Ménière’s disease
• Otosclerosis
• Ruptured ear drums

Treatments of hearing loss range from the preventive use of ear plugs in noisy environments, to wearing hearing aids or undergoing a corrective surgical procedure.

What Types of Hearing Tests Are There?

There are several types of audiometric and related tests for hearing:

• Pure-tone test: A tone is any sound composed of a single sine wave. A pure-tone test measures the softest or quietest tone one can hear in various frequencies. The frequency or cycles-per-second measurement is the Hertz (Hz). Low bass tones have frequency ranges of 50-60 Hz; high-pitched tones, 10,000 Hz or higher. Most humans can hear a range of tones from 250-8,000 Hz, at or just above the whisper volume of 20 dB.
• Tympanometry test: Tympanometry measures energy transmission through the middle ear. It can be used to detect conductive hearing loss, such as perforated ear drums or damaged ossicles (the hammer, anvil, and stirrup). A related test examines the acoustic reflex, which is an involuntary muscle contraction of the middle ear in response to loud sounds.
• Weber test: The Weber test involves the placement of a tuning fork on the mastoid bone behind the ear. When the fork is struck, the audiologist can measure how effectively sound travels to the inner ear. Weber tests are often accompanied by the Rinne test, in which the air and bone conduction of sound are compared for a particular patient.
• Word-recognition test: This test documents a person’s ability to pick out spoken words against a backdrop of noise.

Hearing loss can be measured over time, by comparing the most recent pure-tone test with earlier ones. Mild or moderate losses fall in the range of 25 to 65 dBs; more severe losses range from 66 to over 90 dBs.

What Should I Expect from an Audiometry Test?

Before the Test

No preparation is required for audiometric evaluations. Testing is painless, rarely takes more than an hour, and involves no risks to your health.

During the Test

During the examination you will sit in a soundproof room. Earphones connected to a testing machine will be placed in both ears. The audiologist will use the machine to generate sounds, either tones or words, that are delivered first to one ear, then to the other. He or she will ask you to acknowledge whether you’re hearing them. Your responses will be analyzed for declines in your range of hearing. Additional tests, including those with tuning forks and those involving middle-ear conduction, will be administered before or after the pure-tone and word-recognition examinations.

After the Test

Your audiologist will review the results with you. A record of the test will be sent to your primary care or other referring physician. You will be able to discuss treatment options with him or her.