Casio EXILIM C721 - Manual (Page 206)

205
Safety
What is Hearing Aid Compatibility?
The Federal Communications Commission has implemented rules
and a rating system designed to enable people who wear hearing
aids to more effectively use these wireless telecommunications
devices. The standard for compatibility of digital wireless phones
with hearing aids is set forth in American National Standard
Institute (ANSI) standard C63.19. There are two sets of ANSI
standards with ratings from one to four (four being the best
rating): an “M” rating for reduced interference making it easier
to hear conversations on the phone when using the hearing aid
microphone, and a “T” rating that enables the phone to be used
with hearing aids operating in the telecoil mode thus reducing
unwanted background noise.
How will I know which wireless phones are Hearing
Aid Compatible?
The Hearing Aid Compatibility rating is displayed on the wireless
phone box.
A phone is considered Hearing Aid Compatible for acoustic
coupling (microphone mode) if it has an “M3” or “M4” rating. A
digital wireless phone is considered Hearing Aid Compatible for
inductive coupling (telecoil mode) if it has a “T3” or “T4” rating.
M 3 + M 2 = 5 T 3 + T 2 = 5 M 3 + M 2 = 5 T 3 + T 2 = 5