Wednesday, March 31, 2004

Practice safer sound

Over 26 million Americans suffer with some degree of hearing loss. Trauma, disease, age, medications, and noise exposure are some factors that contribute to hearing loss.

Musicians, racecar drivers, and factory workers depend on their ears to make a living and aspiring musicians begin at an early age. These folks find themselves in a catch-22. We know that repeated exposure to loud sound can cause irreversible hearing loss and that the average volume in each of these areas exceeds what has been deemed safe by the Occupational Safety and Health Administration.

Consider that OSHA requires factory workers be exposed to no more than 95 dBA in an 8-hour period. Major sporting events have been measured in excess of 120 dBA, which is safe for less than one hour. Recent media reports that football games have created a swell of complaints about the volume. An old chain saw exposes the user to about 125 dBA, safe for less than one minute. The average personal CD player at the 5 out of 10 settings is exposing the wearer to about 94 dBA. A .38 special gun blast has been measured at 144 dBA and a .44 magnum at 156 dBA. Finally, a jet engine at 100 feet is presenting around 140 dBA, not safe for any period of time.

Temporary threshold shift is the temporary hearing loss caused by exposure to unsafe levels and typically goes away after several days. Warning signs include ringing in the ears (tinnitus), stuffiness/pressure in the ears (also described as a cottony sensation), asking for repetitions, and /or a need for increased volume.  Repeated exposure and recurrent episodes of TTS may lead to permanent threshold shift, or irreversible, measurable hearing loss. It does not get better.

Prevention is the key to avoid the suffering experienced by so many who have not practiced safe listening. Sound level measurements, hearing tests, hearing protection devices, and assistive listening devices and hearing aids, comprise the arsenal of the audiologist offering comprehensive hearing conservation.

Sound level measurements may be completed on-site with sound level meters or dosimeters. These measurements indicate the source exposure level and the individual’s exposure over time. Identifying the culprit and its levels is the necessary first-step in determining the type and degree of hearing protection required.

Hearing tests determine the presence, type and degree of hearing loss. The audiologist tests how much volume or intensity is needed to barely hear the pitches or frequencies presented. Since we don’t communicate with tones, but rather speech, the examiner completes testing to determine how well the listener understands speech. Learning the level of distortion and the volume tolerable provides additional clues about the status of the listener’s ears.

Hearing protection devices are available as single-use foam inserts, silicone or vinyl earplugs, electronic shooter’s plugs, and musician ear level monitors.  Electronic shooter’s plugs and musician monitors are available as custom or generic models and are available with digital circuitry. Whether you are a hunter, shooter, fireman, policeman, musician, motorcyclist, factory worker, racecar driver, or high school/college band member, there is a hearing protection device for you.

Assistive listening devices range from television and telephone amplifiers to closed-caption decoders and auditorium/church listening devices, as well as alerting devices or even hearing ear dogs. A TV Ears user listens at a different level without the two interfering with each other’s enjoyment. Telephone amplifiers are available as built-ins or add-ons to your current equipment. Most churches and public facilities offer some sort of personal amplification for attendees. Hearing ear dogs are trained to alert their hearing impaired owner to certain sounds, such as a telephone, doorbell, oven timer, smoke detector, alarm clock, or crying baby.  Hearing aids are available in many styles, circuitry options and even multiple colors.