Advanced technology has allowed hearing care providers to schedule patients more seamlessly, test patients more efficiently, and fill their schedules more completely. However, it is important to remember that taking a few minutes to perform a functional check of your test equipment can prevent a small problem from escalating into a serious equipment malfunction resulting in canceled appointments and lost revenue. In today's economy, when everyone is looking for ways to save money, avoiding unnecessary service calls is important.
This article will focus on “an ounce of prevention” that practitioners can apply to keep their audiometers functioning optimally.
THE DAILY LISTENING CHECK
It is essential to perform a daily listening check on your audiometer. The audiometer should be turned on and a continuous tone presented to each of the transducers. Check the transducers for static and intermittency. You can do this by moving the cords around, especially where they connect to the transducer. Crackling or diminished sound levels indicate a problem. Often there is a simple solution: Clean the contacts of the transducer and the jacks on the jack panel. Use a contact cleaner with a lubricant and tighten the screws to the jacks. Make sure to check all the transducers.
On any audiometer, it is helpful to have a baseline hearing test on a normal-hearing subject. If you suspect a problem, perform another baseline test on the same person and compare the results. This should be rechecked regularly in addition to the daily listening check. You can also purchase a bio-acoustic simulator to serve as the standard for the daily hearing test. This is especially helpful if a normal listener may not always be available. The bio-acoustic simulator provides a consistent threshold response in very little time.
CARE AND INSPECTION PROCEDURES
Insert earphones should be checked for moisture or debris in the tubing. Never cut the length of the tubing, as this will affect the calibration. Take care when removing the disposable foam tips that you don't also remove the connector to the tubing. Audiometer and ABR inserts are not the same and some of the tips may contain filters, so check with your service technician to make sure you are using the proper replacement tip. It is a good idea to have an extra set of tubing available at all times.
Examine headphones to make sure the headband has sufficient tension and does not show any cracks. Be careful never to place pressure or liquids on the diaphragm of the earphones. The headphone cushions should also be clean and not cracked. Disposable earphone covers can be used for infection control, but the earphone cushions should be replaced during the yearly calibration—or sooner if needed. It is also critical to remember that earphones are not interchangeable. Each transducer is calibrated to a specific audiometer so it cannot be swapped for another if there is a problem.
The screws on the back of the bone oscillator must be checked to make sure they are secure. It is also important to listen for any intermittency or the presence of crackling through the bone oscillator as well. If the bone oscillator is dropped repeatedly, that can affect its calibration. If that occurs, have your service technician check the calibration.
Sound field speakers
You should check sound field speakers to make sure all the connections are tight and clean. If you hear static or crackling, try using contact cleaner. Connections for most speakers are accessible at the bottom of the speaker so you don't need to remove the speaker from the wall. It is not typically recommended that speakers be connected via the jack panel. Instead, the wires should be fed through the panel via the pass-through and connected directly to the audiometer.
If the speakers are not mounted to the sound room wall, take care not to move them. If they are moved, make sure to return them to exactly where they were. Moving speakers to a different position or location will affect the calibration. If that happens, the speakers will need to be re-calibrated by the service technician.
Talk-forward and talk-back microphones are not interchangeable. These microphones vary among manufacturers, so if there is a problem with either type of microphone, it should be replaced with the manufacturer's recommended microphone. Some of these microphones have batteries. These should be checked first to avoid replacing a costly microphone when the problem is simply a dead battery.
As previously noted, a contact cleaner can be used to clean the jacks in the jack panel. If a problem is noted, first try a connection that you know is good to determine if the jack is indeed the source of the issue. If you find that the patch cord is bad, replace it with a patch cord with gold plugs. These gold plug patch cords are the most consistent and reliable. When replacing a patch cord, it is important to make sure that the cord has the proper type of plug, either a stereo or mono plug.
Finally, the pass-through opening in the jack panel must be sealed after installation to prevent extraneous noises from passing through. Please note, some of the newer PC audiometers don't use the booth's jack panel. Therefore, it is important to check all the connections where they plug in directly to the hardware box. The USB connection must be secure and the software properly installed and configured.
Patient response/hand switch
The easiest way to find out if there is a problem in the patient response/hand switch is to unplug the switch from the jack panel and plug it directly into the back of the audiometer. If the switch works when plugged into the audiometer, the problem is in the jack panel or patch cord. If the switch doesn't work when it's plugged directly into the audiometer, then it needs to be replaced.
Again, patient response switches differ and are not interchangeable, so it's important that a replacement switch be wired appropriately for your audiometer. Mixing patient response switching from one audiometer to another may not work and can prove frustrating, as a switch might work on one audiometer and not another due to the wiring specifications of that piece of equipment. It is important to consult the service technician to make sure the correct switch is used.
We also recommend keeping the area around the audiometer free of dust and debris. This can be done either by simple dusting or by using canned air. This cleaning should be done regularly behind the equipment to reduce the likelihood of dust building up on the connections. Maintaining all cords in an organized manner on hooks or shelves and not leaving them on the floor will help prevent accidental damage from cleaning and vacuums. It is also wise to keep liquids well away from the equipment.
We hope that by following these suggestions for “an ounce of prevention” you will be spared the time and money it costs to cure common audiometer problems and issues. For more information, please contact the local National Association of Special Instrument Distributors (NASED) Certified Technician. A complete list of NASED-certified technicians is available at www.nased.com.