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Telephones and Hearing Aids

Telephones and Hearing Aid Compatibility

Induction Loop Environments

Today's telephones come in many shapes and sizes, offering few/many to simple/complicated features and functions. Signal transmission is not always constant and as a result, hearing and understanding speech clearly when using today's phones is difficult even for individuals without hearing impairments.

Telephone use and hearing aid compatibility have long been at odds. Hearing aid users have struggled with poor hearing aid/telephone compatibility, primarily because of feedback. Feedback occurs when placing the phone to the hearing aid ear and having a squealing sound result instead of the benefit of louder and clearer speech. Simply put, this occurs because of too little space for the amplified sound from the hearing aid to exist: in other worse, the phone is too close to external microphone of the hearing aid which is "on". Many hearing aid users will simply give up in trying to use the phone and hearing aid or take the hearing aid out when speaking on the phone (which can lead to loss/damage).

Many of today's hearing aids, in various style choices, have a telecoil. Telecoils were created to bridge communication between the telephone receiver and the hearing aid. When the hearing aid is switched to a telecoil program (usually accessed via a switch or program button), the external microphone of the hearing aid is turned "off" and the magnetic sensitivity of the phone is now available to receive the magnetic energy from the hearing aid's telecoil (sometimes referred to as t-coil). This is accomplished by turning the magnetic energy emitted from the phone, into electrical energy. What this provides for the hearing aid user, is elimination of feedback (high pitch squealing) and allowing for better, clear speech hearing and understanding. Cell phones, however, do not produce the same magnetic field and are not consistently compatible or successful.

Many cell phones are advertised as "hearing aid compatible". This means that there is reduced radio frequency energy (RRE) compared to the average allowable level in cell phone communications. It does not, however, always mean that a telecoil can or should be used to gain access to cell phone communications. Radio frequency energy (RFE) is the current that is generated for wireless broadcasting and communications. Allowable amounts are regulated by the FCC, ANSI and EEI. Even the allowable amounts, however, can interfere with medical equipment and therefore can affect the performance of a telecoil in a hearing aid (as it is classified as a medical device). In addition to the RFE interference, cell phones themselves can generate their own "magnetic interference, compounding the problem (backlighting on the display or keypad, the battery itself, the circuit board and its electronic composition).

So, what's a person to do? Well, the FCC has mandated (2006 is the most recent) that providers (cell phone companies/vendors) make available 5 handsets that are rated M3 or T3 and that these must be available for testing in-store. The reason for this mandate, as one can guess, is because of the increase in cell phone usage away from land lines and because of the difficulty in speech hearing and understanding even when using a hearing aid telecoil.

What are the ratings and what do they mean? Acoustic or microphone coupling is designated by M while telecoil coupling is designated by T. The higher the rating, the lower the interference, the better the performance. The best rating would be M4 and T4. Hearing aid users should look for phones that are rated M3/T3 or M4/T4. Don't forget: this does not guarantee perfect results and that to minimize interference, shut off options such as backlighting and keyboard displays to minimize the phone's own magnetic interference.

Hearing impaired individuals should also look for the following features to cell phones to maximize the best communication success:

  • vibrating ringer
  • choice of ring tones
  • volume control
  • visual displays for call functions
  • text messaging, email, instant messaging
  • T-coil compability
  • TTY compatibility
  • neckloop or silhouette compatible
  • 2.5 mm audio jack

Many of the cell phone companies have website access and when in these websites, search for "hearing aid compatible". The following are also great website resources:

The audiologist professional should review the importance and variety of telephone options during the hearing aid consultation. Telecoils can be ordered that are more "automatic" or that can be accessed using a manual program button. There are advantages/disadvantages for each product and the audiologist will review these differences to determine which of or if both of the telephone option products are best for you and your hearing needs.

The hearing aid industry has also arrived at manufacturing hearing aids that have Bluetooth compatibility platforms. Many patients ask the simple question "What is Bluetooth?" Bluetooth is a technology that allows devices to communicate wirelessly to each other when they are in a specific range. Several hearing aid manufacturers have created a remote control or streaming device that can be paired to another device (such as a cell phone) that allows the signal from that device (cell phone) to be "streamed" or transmitted to and heard in both hearing aids. These devices may also accommodate other listening devices such as iPods, MP3 players, DVD players, TV, computers and more.

For patients who do not have a true Bluetooth platform function hearing aid system, there are other devices that can be made to have Bluetooth compatibility and work effectively with hearing aid use as well.

Induction Loops

Another important function of a telecoil can be to adapt or be wirelessly connected to an induction loop. An induction loop is a wired environment that allows patients, with hearing aid telecoils who are located in the wired enclosure, to wirelessly hear the transmission of sound from the PA or amplifying device, through their hearing aids. The hearing aid user flips to his telecoil program and once this is turned on, sound running through the induction loop is directly and wirelessly transmitted into the person's hearing aids (via the telecoil), blocking out background noise and allowing for a more enriched and successful listening experience. The signage that is displayed when entering an induction loop environment is listed below:

Go to the following link and read about the benefits of the installation of induction loop technology at the Gerald R. Ford International Airport:


More and more facilities are installing hearing loops that make all the difference in listening enjoyment. The following are additional websites:

ASC Hearing Clinic in July, 2008, donated two hearing loop systems, one at the Cadillac High School Auditorium and the other at Baker College, Cadillac Campus', Student Center. Many patients and patient's family and friends have commented on what a positive difference these systems have provided.

Induction loops can also be installed in the home setting. The following website provides the variety and ability for purchase:


Hearing aid manufacturers and advancement in technologies continue to provide the hearing impaired with options for success.


Mahaffey, Melissa, Au.D.: eAudiology on demand seminar. "Hearing Aids and Cell Phones - Can You Hear Me Now?". January 21, 2009 (initial presentation)


The ASHA Leader, March 29, 2009 Publication (or visit www.asha.org)