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M-Ratings: Phones rated M3 or M4 meet FCC requirements and are likely to generate less interference to
hearing devices than phones that are not labeled. M4 is the better/higher of the two ratings.
Hearing devices may also be rated. Your hearing device manufacturer or hearing health professional may
help you find this rating. Higher ratings mean that the hearing device is relatively immune to interference
noise. The hearing aid and wireless phone rating values are then added together. A sum of 5 is considered
acceptable for normal use. A sum of 6 is considered for best use.
In the above example, if a hearing aid meets the M2 level rating and the wireless phone meets the M3 level
rating, the sum of the two values equal M5. This should provide the hearing aid user with “normal usage”
while using their hearing aid with the particular wireless phone. “Normal usage” in this context is defined as a
signal quality that is acceptable for normal operation.
The M mark is intended to be synonymous with the U mark. The T mark is intended to be synonymous with
the UT mark. The M and T marks are recommended by the Alliance for Telecommunications Industries
Solutions (ATIS). The U and UT marks are referenced in Section 20.19 of the FCC Rules. The HAC rating
and measurement procedure are described in the American National Standards Institute (ANSI) C63.19
standard.
For information about hearing aids and digital wireless phone
• FCC Hearing Aid Compatibility and Volume Control
http://www.fcc.gov/cgb/dro/hearing.html
• Gallaudet University, RERC
http://tap.gallaudet.edu/DigWireless.KS/DigWireless.htm
• Self Help for Hard of Hearing People Inc.
[SHHH]
http://www.hearingloss.org/hat/TIPWirelessPhones.htm
• The Hearing Aid Compatibility FCC Order
http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-03-168A1.pdf
FDA Consumer Update
U.S. Food and Drug Administration – Center for Devices and Radiological Health Consumer Update on
Wireless Phones
1. Do wireless phones pose a health hazard?
The available scientific evidence does not show that any health problems are associated with using wireless
phones. There is no proof, however, that wireless phones are absolutely safe. Wireless phones emit low
levels of radiofrequency energy (RF) in the microwave range while being used. They also emit very low
levels of RF when in the stand-by mode.
Whereas high levels of RF can produce health effects (by heating tissue), exposure to low-level RF that
does not produce heating effects causes no known adverse health effects. Many studies of low-level RF
exposures have not found any biological effects.
Some studies have suggested that some biological effects may occur, but such findings have not been
confirmed by additional research. In some cases, other researchers have had difficulty in reproducing those
studies, or in determining the reasons for inconsistent results.
2. What is FDA’s role concerning the safety of wireless phones?
Under the law, FDA does not review the safety of radiation-emitting consumer products such as wireless
phones before they can be sold, as it does with new drugs or medical devices. However, the agency has
authority to take action if wireless phones are shown to emit radiofrequency energy (RF) at a level that is
hazardous to the user. In such a case, FDA could require the manufacturers of wireless phones to notify
users of the health hazard and to repair, replace or recall the phones so that the hazard no longer exists.
Although the existing scientific data do not justify FDA regulatory actions, FDA has urged the wireless phone
industry to take a number of steps, including the following:
•
Support needed research into possible biological effects of RF of the type emitted by wireless
phones;
•
Design wireless phones in a way that minimizes any RF exposure to the user that is not necessary
for device function;
