OPTICAL CHARACTER RECOGNITION (OCR)
Many visually impaired individuals benefit from the use of optical character
recognition to convert print documents into a format usable to them. In some
cases, there are OCR systems that can convert directly from print to spoken
output using a speech synthesizer. In other cases, the OCR can convert from
print to a PC file that may be read using a screen reader package and speech
synthesizer, or by using a refreshable braille display, or a large print
display device. Once the print material has been converted to a standard PC
file, the full range of accommodation tools can be used to give the
individual the preferred mode of access to the information.
- Quality of printed material to be scanned - Some OCR devices
will adequately recognize only letter quality printed text.
Others are able to scan and recognize draft quality text or poor
quality copies of reproduced materials. At this time, optical
character recognition of handwritten materials is not commercially
- Format of printed material to be scanned - Some OCR
devices can only scan and recognize materials on a standard sized
page that is printed in portrait format. Other OCR devices can
also recognize materials that are printed landscape or sideways on
a page. There are also differences in how different scanning
devices are able to handle multi-column text. Prior to deciding
on an OCR device, a test scan and recognition of materials that
are of the format and quality the user will typically be scanning
should be done.
- Stand-alone speech output - Some OCR's can give speech output of
the printed material without actually being connected to a PC at
- Is there a need for speech output of printed text in a
stand-alone mode vs through the PC?
- Choice of scanners - Some OCR devices are able to work with a
number of different scanner platforms. Others are limited to one
or two choices of possible scanners. If the department has
already purchased scanners in the past and just needs to optimize
the OCR capabilities for the individual, this may be a
- User interface - The OCR devices that are being marketed
specifically for use by blind individuals have ensured that their
user interface is not dependent on the user responding to visual
cues on the scanner. Some of the OCR devices that are not
specifically marketed to visually impaired users may also be
usable, but this should be carefully examined prior to purchase.
In addition, the OCR devices specifically marketed to visually
impaired users usually have the user interface specifically
designed to easily work with screen reader packages and speech
synthesizers to give spoken output to the user.
- Other considerations and questions that should be addressed include:
- Does the scanner have an automatic page feed for multi-paged documents?
- How well can the scanner handle bound documents? Is the
recognition satisfactory as the print nears the bound edge?
- Can several pages be scanned before the recognition effort
begins, or must each section or page be scanned and recognized
before moving on? In some cases, the OCR devices that allow
several pages to be scanned before recognition occurs can save the
individual time by allowing them to go on to another task while
the recognition is occurring.
- How long does it take for a typical page to be scanned?
- How long does it take for a typical page to be recognized?
- How many pages can be scanned in one session? Is there a memory
- Is portability of the unit a factor?
- Hardware configuration and software compatibility considerations
- See the "General Hardware Configuration and Software
Compatibility Considerations" listed at the beginning of this
Speech recognition can be used by some blind computer users to augment either
the regular computer keyboard or a braille input device. Typically, blind
computer users are using the speech recognition to either make command
selections from a pull-down menu or to give voice mouse commands. In many
cases, mouse movements can be accomplished by using keyboard commands, but
this is often slow and cumbersome. Speech recognition systems that allow the
individual to speak the mouse commands and movements to be performed may
offer an easier and more productive alternative to mouse control. For more
information on speech recognition, see the section on accommodating
individuals with mobility impairments in this appendix.
- Will the speech recognition package work well with the speech
output, refreshable braille package, or other accommodation
package also in use?
- How is feedback given to the visually impaired user that the
desired command or movement has been executed?
Although CD-ROM can be a very effective tool for visually impaired users, not
all CD-ROMs are usable by individuals with visual impairments. Typically,
the user will need to access the information using their accommodation tools
such as speech output, large print, or refreshable braille.
- Image file vs ASCII file - Is the information stored as an image
file or as an ASCII file? To be accessible by many visually
impaired users, the ASCII file format is needed.
- CD-ROM interface - The user interface to access the files on the
CD-ROM may also present problems for the visually impaired user.
Some CD-ROM producers are using a graphical user interface (GUI)
rather than an ASCII-based interface.
- Text annotations - Do any pictures presented on the CD-ROM have
an ASCII text annotation explaining the information presented in
the picture? Although this is not crucial in every case, it is a
- Graphic/text install option - Does the CD-ROM interface offer an
option during the install process that would give the user the
choice to load a graphic interface or a text interface?
Many visually impaired users may benefit greatly from using various
combinations of the devices previously discussed in this section.
- Large print and speech output - Many individuals with low vision
are able to read large format displays, but may not be able to
read even this enlarged text over long periods of time without
significant eye strain and fatigue. Adding speech output may
significantly lengthen the time they could productively work on a
given task. Many users will use speech output for reviewing
material for content and switch to visual display for final
editing or when the speech output is unclear or difficult to
understand. For some individuals with a degenerative eye
condition, it may be helpful to add speech output while there is
still some degree of usable vision to help in the transition from
dealing with the screen visually to dealing with it auditorily.
- Speech and refreshable braille - Many blind individuals may
benefit from using a combination of speech output and a
refreshable braille display. Speech may be the preferred means
for reviewing text and the refreshable braille for doing the final
edit or reviewing items such as acronyms that may not convert well
to speech output. Others may find speech output the preferred
mode in one application and refreshable braille in another. For
instance, many programming languages use contracted words and
numerous punctuation symbols that may be easier to understand
using refreshable braille. On the other hand, word processing
tasks may proceed more quickly using speech output rather than
having to constantly switch hands from the keyboard to the braille
display to type and review text.
The key to all the accommodation solutions discussed is to involve the
individual user throughout the decision process.
C. Accommodating Users with Hearing Impairment
In general, deaf people depend more upon visual skills for communication and
information from their environment while hard of hearing people try to
enhance their usable hearing and still rely on auditory input more than
visual input. It is key that the individual participate in the process of
identifying the accommodation solution to ensure it is the proper approach
for that particular individual and their needs.
Both hard of hearing individuals with hearing aids and those who do not wear
a hearing aid may benefit from devices that provide amplification of standard
auditory input. Depending on the cause of hearing loss, amplification
devices may not help some hard of hearing individuals. Although many
individuals with a hearing loss may be quite knowledgeable about the range of
amplification devices available, there are others that may not be aware of
these devices. This is especially true of older individuals who often
consider their progressive hearing loss a part of the normal aging process
and think there is nothing that can be done but to accept it and go on. The
best way for a hard of hearing individual to determine which amplification
devices may be of benefit to them is to actually try several of the devices
if at all possible. If one amplification device does not provide sufficient
amplification for the individual, a different device or a different style of
device may still be of benefit. In many cases, consulting with a service
center having expertise in assistive listening devices may be beneficial.
It should be kept in mind that many deaf individuals also wear hearing aids.
For these individuals, the hearing aid allows them to hear loud sounds, but
not to discriminate speech regardless of the amount of amplification.
VISUAL REDUNDANCY OF AUDITORY INFORMATION
Many of the accommodations discussed for individuals who are deaf focus on the
need for visual redundancy to augment what others hear auditorily. Visual
redundancy can be accomplished for computer tasks, telecommunications tasks,
one-to-one communications and group meetings. Each of these areas will be
discussed in this section on visual redundancy.
Most hearing impaired users currently do not experience significant
difficulties with computer technology. Adding a means for visual redundancy
of auditory signals like the computer beep will often decrease some of the
frustrations that may occur working in a computer environment. Although a
user with a hearing impairment would eventually determine that something is
wrong from the lack of change on the visual display, it can be a frustrating
experience. Likewise, hearing a long string of beeps until this realization
is made may be frustrating to the coworkers in the office. Software is
available for PCs that will either flash the screen or display the word BEEP
where the cursor is located whenever the auditory beep is sounded by the PC
speaker. For any offices using Macintosh computers, the ability to change
the computer beep to a flashing bar on the screen is a built-in function of
the operating system utilities.
Many Federal offices have large nonstandard application packages written and
developed to specifically meet the needs of the agency. When new programs
are being developed, redundant visual and auditory cues should be
incorporated so that both visually impaired and hearing impaired individuals
may fully use the systems.
To accommodate hearing impaired persons that communicate using American Sign
Language or need an oral interpreter, professional interpreters are available
on a contractual basis or may be hired by the agency. Many hearing
individuals that can converse using sign language are not qualified to be
sign language interpreters. This is a specialized skill requiring years of
training. Arrangements for a certified sign language interpreter should be
made for interpreting at meetings, conferences, and training courses. When
arranging for interpreter services for a specific meeting or event the
following questions will need to be answered before the interpreter service
can provide a qualified interpreter.
- What is the date, time, and location of the meeting?
- Who will they be interpreting for? Is it for one specific
person or for a group of people? If it is for a group of deaf
individuals, how many are expected?
- Which sign language is preferred? Many deaf individuals prefer
American Sign Language, but some may prefer Signed English or a
different version of sign language. Some deaf individuals do not
know sign language, but rely on having an oral interpreter who
will mouth the speakers' words and give additional visual cues to
the deaf individual to assist with accurate lip reading. If
interpreter services are being secured for an individual, they
should be asked what version of sign language they prefer.
- What is the topic of the meeting? If it is a technical meeting,
a sign language interpreter proficient in those signs pertinent to
the topic will be needed.
- How long is the meeting? Sign language interpretation can be
very tiring for the interpreter. If a meeting will exceed two
hours, typically two interpreters are needed so they can take
turns throughout the meeting.
- Will the interpreter be voicing for the deaf individual or only
signing what is spoken? Some deaf individuals speak clearly and
would rather speak for themselves. Others are non-vocal or do not
feel they speak clearly enough in public situations and prefer
that the interpreter voice what they sign.
Other interpreter related considerations that should be taken into account are:
- Positioning - In an auditorium, the interpreter should be
positioned on the stage or platform close to the speaker. The
deaf individuals watching the interpreter will be watching both
the speaker for visual cues and the interpreter for the sign
language interpretation. In a team meeting where several
individuals will be talking, the interpreter should be positioned
where the deaf individual can see the interpreter clearly and
still be able to participate fully in the meeting.
- Lighting - Adequate lighting is essential for the interpreter to
be seen clearly. This is particularly important to consider when
overheads or slides are going to be used and room lighting turned
down. A spotlight that can be directed on the interpreter may be
a good option in this situation since the interpreter will need to
be positioned where both the viewing screen and the interpreter
can be seen.
- Seating - In an auditorium or a large meeting, seating in the
front few rows should be reserved for individuals who need to
watch the sign language interpreter. All the efforts to have an
interpreter present will not accomplish the intended effect if the
individuals who need the service are not able to clearly see the
For a person that is hard of hearing or deaf, the normal sounds and tones
that alert us to take action, such as a phone ringing, may not be heard.
Frequently, a TDD or TDD compatible device will be purchased without giving
any thought to how the hearing impaired individual will be able to determine
they have an incoming call. A non-auditory mechanism needs to be provided to
alert the individual to telephone rings and other important sounds such as a
door buzzer, fire alarm, or other emergency alarm. Several approaches should
be considered when determining the best method of alerting a hard of hearing
or deaf individual by a non-auditory mechanism.
- Flashing light - Devices can be connected to a transmitter that
directs a signal to a receiver that causes a light to flash on and
off. The transmitters can be set to cause the light to flash in a
different pattern for different devices so the individual knows
what action is needed. Considerations:
- Can the individual see the flashing light from anywhere they are
likely to be in the office?
- Vibrating personal alerting device - An alternative to the
flashing light that is more effective in some cases, is a
vibrating personal alerting device. The personal alerting device
can provide notification of several sounds through distinct
indicator lights for the phone, door buzzer, and emergency alarms.
- One key disadvantage of using this device for emergency alarm
signal notification is the limited range of the transmitters.
Currently, many of the vibrating personal alerting devices have an
effective range limitation of 100 feet from the transmitter to the
- What are the specific alerts that need to be activated?
- How many different alerts are there?
- Where is the device worn so the person feels the vibration?
Some are designed to be worn on a belt or waistband. Others are
designed to be worn on the wrist. Is it comfortable enough and
unobtrusive enough that the individual will wear it on a
- What is the battery life? Does the device have a low battery
- Beepers/pagers - Many beepers commonly in use now have an option
to have the beeper vibrate rather than emit an auditory signal.
Beepers that also have the ability to display alpha characters in
addition to numbers may offer significant advantages in augmenting
other alerting systems or communications systems in the office.
An alpha/numeric beeper with the vibrating option can be used for
short messages about changes in meeting plans, building
emergencies, etc. Considerations:
- What is the range of the beeper?
- How quickly is the signal transmitted to the beeper from the
time the message is initiated?
- How is the message initiated? via touch-tone telephone keypad?
from a "message station" PC? through a special operator?
- Does the device have a low battery indicator?
- Will the beeper keep repeating the message until some action is
taken by the user (e.g. pushing a button on the beeper) or is it
given one time only?
- What is the limit on the message length?
- Fire alarms - A combination of several approaches may be
necessary to provide deaf individuals adequate notification of
emergency alarms. Possibilities include:
- Many existing building fire alarm systems can be wired to
transmit a signal to one of the vibrating personal alerting
devices mentioned above. A transmitter might need to be connected
to each fire alarm to give full coverage for the individual
throughout the building since the range limitation of each
transmitter is approximately 100 feet.
- Fire systems can be adapted to also generate a message to a
beeper when the fire alarms are activated.
- There are fire alarm systems that meet the building code
requirements for office buildings that add a strobe light to the
existing fire system. These systems may address the need to alert
any hearing impaired visitors to the building in addition to
regular employees. Care should be taken to ensure the strobe
lights can be seen from conference rooms, and other public access
areas, not just the hallways.
- There are also smaller smoke alarms, similar to those used for
home use, that have both the auditory signal and a strobe light.
These may be placed in the office of hearing impaired employees to
augment the building wide system, but should not be the sole
method of alerting the individual to a fire in the building. By
the time a local smoke alarm is activated, it may be too late to
safely exit a large Federal building.
- Tone amplification - For some hard of hearing individuals, a
visual alerting system may not be necessary if the auditory input
can be modified. Considerations:
- Frequency range - Telephones can often be equipped with a tone
ringer device that converts the normal ring of the phone into a
frequency range more easily heard by the individual.
- Tone intensity - A device can be added that makes the ring
significantly louder. The general office setting and the need to
protect the hearing of others in the same office area needs to be
considered prior to significantly amplifying a telephone ring.
Videos are increasingly being used within the Federal government. Deaf and
hard of hearing individuals are often unable to fully utilize or benefit from
videos since videos often rely heavily on auditory information. Captioning
videos makes this medium fully accessible to hearing impaired individuals.
There are two types of captions: open captions and closed captions. The
closed caption format provides an embedded signal with the printed words
synchronized to the spoken dialogue. To project the embedded signal as
captioned words on the screen, the video player must be connected to a
telecaption decoder. Without the decoder, a closed captioned video looks
just like a video that has not been captioned.
When open captioning is used, a telecaption decoder is not needed. The
captioning is displayed any time the video is played. Open captioning ensures
that videos are accessible to hearing impaired individuals from all video
players. Any office that has access to a video player can show the video in
a fully accessible format for hearing impaired individuals. In addition, if
the viewing room is noisy, or portions of the auditory output from the video
are unclear, then the captioning benefits all the viewers.
Any video-based media produced for instructional, training, or informational
purposes either by an agency or for an agency should be captioned so the
information presented is accessible to hearing-impaired viewers. There are
several organizations available on a contract basis that will provide the
expertise to either open caption or close caption videos. In addition, there
are several PC based packages that enable the agency to open caption or close
caption their own videos. When the video is first being planned, captioning
should be discussed with the graphics department that will be performing the
actual video filming. The composition of the shot may need to be changed
slightly to ensure that no critical or key elements of the visual display
will be lost when the captioning is overlaid on the bottom lines of the
When the agency is purchasing videos, they should inquire about the
availability of the video in a captioned format. When purchasing video
tapes, it may be possible to obtain permission from the copyright holder to
caption the videos if they are not available in a captioned format.
TDDs - TELECOMMUNICATIONS DEVICES FOR THE DEAF
Many deaf and speech impaired individuals use a TDD (telecommunications
device for the deaf) to communicate over the telephone. A TDD is also used
by many hard of hearing individuals that are not adequately accommodated by a
telephone amplification device. A TDD permits a hearing impaired person to
communicate over a standard telephone line with another TDD user or through a
relay operator to reach a non-TDD user. The TDD displays a line of text for
the person to read rather than using auditory output like a standard phone or
a phone equipped with an amplification device. TDDs are also commonly
referred to as TTYs, their older name. There is a fairly broad range of TDD
and TDD compatible devices available. Considerations:
- ASCII and Baudot compatibility - TDDs have traditionally used
the older 5 bit, 45.5 baud Baudot code for communications. This
code is significantly different from the PC ASCII code that many
computer users in the Federal government are more familiar with
using. Some TDDs are able to accept calls from both the older
model Baudot only TDD and from the newer Baudot and ASCII TDDs or
from personal computers sending at 300 Baud ASCII. TDDs that
support Baudot only are rapidly becoming obsolete technology as
more TDDs that support both Baudot and ASCII are being produced
- Display - The LED display that is used to display the
information being received on the TDD can be either a single line
display or multi-line. Multi- line displays may offer 2 lines, 4
lines or even 25 lines. The lines may be from 20 characters to 80
characters on a line. The size of the display and the characters
themselves can also be different from device to device. The
nature of the work being done may indicate a need for a multi-line
display. The amount of time spent using the TDD or a visual
impairment may indicate the need for a large character display
that works with the TDD.
- Printer capability - Some TDDs have a built-in printer. Many
others have a printer port that will allow a TDD printer to be
connected. The nature of the work and the need for taking notes
during a conversation would help determine the need for a TDD
printer. It is difficult to both read the LED display as it
scrolls new information and take legible notes at the same time.
If the individual is often receiving addresses or listings of
information such as model numbers and pricing using their TDD, a
printer may be needed.
- Direct connect or acoustic coupler connection? - Many TDDs may
be used with a direct connect mode that allows the phone cable
from the wall to be directly plugged into the TDD. Others have an
acoustic coupler that the regular telephone handset is placed on
when a call is received. Many TDDs, have options for both the
direct connect and acoustic coupler methods of connection. Which
connection method is used depends upon the preferences of the user
and the office setting. If the phone is going to be used for both
voice and TDD calls, then using the phone handset with the
acoustic coupler is preferred. If the phone line is being used as
a TDD only line, then the direct connect method may be preferred,
but not always. For offices on a digital phone network, the phone
network itself will need to be taken into consideration. Using a
TDD through the acoustic coupler presents no problems. For a
direct connection, either a digital to analog board may need to be
added to the telephone system for that line or an analog line may
need to be installed. Consult the agency telecommunications
specialist on this issue.
- Shared use or single person? - Many TDDs in the Federal
government are purchased for use by a single Federal employee who
is a TDD user. Others are purchased by offices that need to be
TDD accessible for public inquiries or inquiries from Federal
employees that are TDD users. Examples are personnel offices, EEO
offices, libraries, IG offices, and offices like the Clearinghouse
on Computer Accommodation. If the TDD is going to be used by
several people in an office then having a TDD that can operate on
battery power may be important. The TDD could stay plugged in to
charge the battery, but when a TDD call was received, anyone in
the office could move the TDD to their desk and use it on battery
mode. Shared use considerations:
- Where will the TDD be positioned? Does everyone have adequate
access to it? How close are all the phones or people that need to
share the TDD?
- Who will be responsible for ensuring it is charged and in
working condition? - If a printer is needed, would an internal
printer be easier to move and use than an external printer?
- Rollover - If a number is listed as either a TDD number or a
voice and TDD number, consideration needs to be given to where
that phone line "rolls" to when it is in use or not answered. If
the line automatically transfers to a second line or to another
office, that office will need a TDD to respond to incoming TDD
- Portability - For a deaf employee who travels extensively, a
second portable unit may be needed. Some portable TDDs fit in the
inside pocket of a man's suit jacket. Considerations:
- How important is portability?
- How much travel does the individual do? Both local travel to
other offices that do not have a TDD and travel out of town should
- Are both Baudot and ASCII capabilities needed? Some portable
TDDs offer the ASCII option.
- Should a portable TDD be purchased for a specific individual or
should several units be purchased for the agency and available for
checkout on an as needed basis?
Personal Computer TDD Compatibility
A personal computer can also be configured to function as a TDD by adding a
special PC/TDD modem that supports both the standard PC code (ASCII) and the
code used by most TDDs (Baudot). Commonly used PC modems are not able to
communicate with a Baudot only TDD. Since there are so many of the older
Baudot only TDDs in use, one of the specialized modems that supports both
Baudot and ASCII is needed. Considerations:
- PC availability - Does the individual already have a PC?
- Connection to the PC - some TDD compatible modems are internal
and use a board slot inside the PC. Others are external modems
and require a serial port. Which method of connection is
- Connection to the telephone system - Both the internal and
external modems require a connection to a telephone line to be
operational. For offices using a digital phone network or those
using electronic key phone sets, the phone network itself will
need to be taken into consideration. For a direct connection,
either a digital to analog board may need to be added to the
telephone system for that line or an analog line may need to be
installed. Consult the agency telecommunications specialist on
- Other PC use - In most cases, the PC is going to be used for
other applications and not be a dedicated TDD. Considerations:
- Call notification - How is the PC user notified when there is an
incoming call? Some packages will make the screen flash to
indicate an incoming call. Some will automatically switch the
user to the TDD communication mode. Others rely on having an
external signalling device installed between the phone line and
the modem to alert the individual.
- TDD to PC Application Switch - If a PC application program is in
use, how easy is it for the user to switch into the TDD
communication mode? Some packages offer an easy "hot key"
function that will quickly switch to the TDD communication mode
and then allow the user to return to their application package
where they were working when the call was received or initiated.
Other packages require the user to save the file they are working
in, exit the application package and then enter the TDD
communication mode. In this case, there are optional memory
management programs that could be added to the PC system to ease
the transition between the application package and the TDD
communication package. It would be up to the user to find,
install, and configure the memory management solution to work with
the TDD communications package.
- Call volume and type - How many calls are expected to be
received each day? Will a high call volume interfere with using
the PC application packages? Do the calls received require the
individual to be looking up information on the PC in order to
respond? In most packages, if the TDD call is left on hold or
inactive for a long period, the modem will assume the call was
interrupted or completed and break the connection.
- Portability - Does the lack of portability of a PC based
solution cause a problem? Would the individual possibly need a
standard TDD or portable TDD in addition to the PC based TDD
- Other Features - PC based TDD communication packages and modems
offer additional features that may be important to the user or the
office installing the system. Some of these are:
- Auto-answer capability - The PC can be configured to have the
TDD compatible modem and software automatically answer calls when
the user is away. The message given can be customized and changed
as needed. The incoming callers can leave a message that is
stored on the PC. Since the PC is being used for incoming message
storage, a significantly larger volume of messages may be stored
than with a standard TDD with auto-answer capabilities.
- Speed dialing - Several of the packages offer a phone listing
mechanism for automated dialing of outgoing calls.
- Speech output - There is one TDD compatible modem that combines
this capability with a mechanism for synthesized speech so the PC
can be used to speak messages to a hearing caller using a standard
voice phone. The hearing caller is able to reply to the hearing
impaired individual using this modem device by using the touch
tone pad of their telephone. The hearing caller may find using
the touch tone pad of their telephone cumbersome for a long
conversation. For some situations, this unique combination may be
quite useful. This modem makes it possible for the PC user to
initiate or accept calls from a TDD, a PC using ASCII
communications, or a hearing caller using a standard touch tone
- Remote message retrieval - Some packages are able to provide the
user with the capability to call in from a remote location and
retrieve the messages stored on their PC by the TDD compatible
software. For an individual doing extensive traveling, this may
be a very important feature.
- Call storage - Several of the packages allow the contents of a
call, both sides of the conversation, to be saved and printed.
- Customized stored messages - Several packages allow the user to
create a message, such as their address, store it, and in the
middle of a conversation with a TDD caller, retrieve and send that
message to the caller. This can be very useful if the individual
often gives the same information to many callers such as
directions to the office, listings of information, or answers to
commonly asked questions.
- PC file use - Some packages allow the user to transmit a PC
ASCII file in the same manner as any customized stored messages
created within the TDD communication software package.
- Hardware configuration and software compatibility considerations
- See the "General Hardware Configuration and Software
Compatibility Considerations" listed at the beginning of this
- Is the PC used for making large database searches or other
similar tasks that occupy the PC for long periods of time in a
mode that could not be interrupted for the user to accept an
- If the PC is used in a terminal emulation mode, how long can the
user stay on a call before the emulation software would drop them?
- Secure agencies - some of the secure agencies will not allow any
modems, internal or external, to be connected to many of the PCs
in the agency. In addition, tempesting requirements may present
another barrier to using a TDD compatible modem.
Speech Amplification for Telephones
There are several methods of amplifying the speech being heard over a
telephone. There are devices designed both for people who use a hearing aid
and for those who do not use a hearing aid.
- Handset amplification - The standard telephone handset can be
replaced by a handset that has an amplification device. The
amplification handset usually has a rotary dial for adjusting the
amount of amplification needed. Considerations:
- Amplification level - How much amplification is needed? Up to
30 db of amplification is available depending upon the specific
handset chosen. Some amplification handsets require the user to
press a button to boost the amplification to its highest levels.
This is a safety feature to protect the hearing of a person that
does not have a hearing impairment that may use that phone.
- Telephone style - What style of telephone will the device be
used with? There are handsets available as replacements for the
standard round handset (G style), or the newer square handset (K
style), or the square with the electronic microscreen style
- In-line amplification - An alternative to using an amplification
handset is to use an in-line amplification device. Most in-line
amplification devices are small devices that plug in between the
telephone base and the existing phone handset. An advantage of
in-line amplifiers is that they add no weight to the telephone
- Amplification level - How much amplification is needed? Volume
increases up to 20 db are possible with an in-line amplification
device. The volume can be adjusted by turning a control wheel
located on the device.
- Telephone style - What style of telephone will the device be
used with? Some in-line amplifiers are designed to work with
specific types of telephone systems. Others are designed to be
universal and work with all modular handset telephones, including
the newer electronic type phones.
- Power needs - Is there an electric power outlet located
conveniently? Most in-line amplification devices require
connection to a standard AC power source.
- Portable amplification devices - Even though a telephone handset
is small enough to be considered portable, there is an even
smaller, more portable option available. It is a small battery
powered device that fits over the receiver on the telephone
handset. A stretch strap holds the device in place.
- Amplification level - What is the level of amplification needed?
Portable devices can be used for up to 20 db of amplification.
- Non-modular jack phones - Does the individual need amplification
for telephones that do not have a modular connection for the
handset. Most public phones or phones in hotels do not have a
modular connection that would allow a handset amplification device
or an in-line amplification device to be connected. Office phones
in some settings are also non-modular.
- Specialized phones - There are phones available that have been
specifically designed for individuals with a hearing loss in the
high frequency range. The individual selects the appropriate
volume using a control button on the phone set. Having the
amplification built into the body of the phone results in a
lighter telephone handset than the handsets that have been
modified to provide amplification. Considerations:
- Compatibility - Will the phone work with the telephone system
installed at the work site? Can the same features available to
others in the office be accessed using this phone set?
- Single site vs multiple sites - Does the individual have the
need for telephone amplification only at one location? If the
individual may need to use several different telephones, a
combination of a specialized phone at their primary worksite and
one of the other amplification devices at the other sites may be
Speech Amplification - Meeting or Conversation
There are several different speech amplification devices that can be used by
hard of hearing individuals in either a meeting or lecture setting. The
needs for the two settings differ based on the need to be hearing the
information being spoken by a single person or the need to hear several
different people in a more interactive conversation or discussion mode. The
needs in different settings will be discussed first and then the different
types of devices that can be used.
- One-to-one meeting - Many hard of hearing individuals can
understand the majority of a conversation in a one-to-one setting
without the use of an amplification device if the speaker speaks
clearly, faces the individual, does not restrict visibility of
mouth movements by a mustache or their hands, does not look down
while speaking, and there is a minimum of other background noise
distractions. If the speaker turns away from the hard of hearing
individual, looks down to read paperwork as they are talking, or
has a tendency to mumble, an amplification device may help make
conversations easier for the hard of hearing individual to fully
understand. Even in situations where the speaker and the listener
are able to communicate adequately, an assistive listening device
may make conversations easier and less fatiguing for the hard of
- Lecture setting - The lecture setting exhibits the same
potential problems in understanding what is spoken as the
one-to-one setting, plus a few more. In a lecture setting the
speaker is usually further away from the hard of hearing
individual. This can significantly decrease the visual cues the
individual has available to augment what they are hearing. In
many cases, the lighting conditions are less than optimal for the
hard of hearing individual to be able to clearly see the speakers
lips and face. This is particularly true if an overhead projector
or slides are being used.
- Group meeting setting - In a group meeting where several
different people may be speaking in a more relaxed and spontaneous
manner, additional difficulties are present. Since the meeting is
spontaneous, the hard of hearing individual may have difficulty
following who is actually speaking and miss quite a bit before
they know which individual to be focusing on. In addition, it is
not always possible to see each person clearly, especially if
their remarks are being directed to someone in the opposite
direction. There is also a high potential for distracting noises
such as papers, people shifting, and side conversations taking
Types of Systems:
- FM system - Most FM systems basically consist of a transmitter
and a receiver that work together. The transmitter connects to a
microphone that a speaker would either wear, such as a lapel
microphone, or have placed near them. The speaker's voice is
broadcast as an FM radio signal to the receiver. The hard of
hearing person with the receiver can use either a set of
headphones similar to those used with a portable radio, or if they
use a hearing aid, a neck loop that will transmit to the T-coil in
their hearing aid.
- Induction loop system - A loop system consists of an amplifier
that drives an audio signal and a loop of wiring that is typically
around the perimeter area of the meeting room. A variety of
microphones can be plugged into the amplifier depending on the
setting of the meeting. The amplified audio signal creates an
electromagnetic field within the area inside the loop. An
individual who is wearing a hearing aid with a T-coil pickup
receives the electromagnetic signal produced by the loop as long
as the individual is within the loop. An individual without a
hearing aid can wear a receiver and headphones to pickup the
signal. The wiring loop can be either permanently installed in
either the ceiling or around the seating area of a room on the
floor. The loop can also be temporarily installed on an as needed
basis if the system is going to be used rarely or in different
rooms. If it is placed on the floor, it should be taped in place
securely to ensure it does not pose a potential hazard for
- Infrared system - An infrared system works using an infrared
transmitted signal instead of a sound based signal. The number of
infrared transmitters needed to adequately cover all areas of a
room differs based on the size and shape of the room. Secure
agencies are particularly interested in infrared systems instead
of FM or loop systems that produce radio or audio signals. The
individual needing amplification would use a receiver and neck
loop or headset depending on whether they use a hearing aid or
- Portability - Several of these systems are small enough and
simple enough to use to be highly portable.
- Is the system being purchased for use in one room or several?
- Does the need exist for a portable system that could be taken to
a site for training classes? For instance, an individual using an
FM system may take the system to a training class. The instructor
would be given a small lapel microphone and FM transmitter to
wear. The hearing impaired individual would wear the FM receiver.
The transmitter and receiver units are small enough to easily fit
in a suit pocket.
- Group meetings vs one-to-one meetings
- In what type of setting does the individual spend most of their time?
- What setting presents the most hearing difficulty for the individual?
- Earphones vs Audio Loop - Does the user prefer to wear earphones
to hear the amplified sound? If so, what type (e.g. radio type,
under the chin version, ear buds, etc.)? If the user wears a
hearing aid, would they prefer the neck loop that will communicate
to the T-coil in the hearing aid?
- Meeting room usage - If the system is being purchased primarily
for providing access in a conference room or auditorium there are
- Should the amplification system be wired directly into the
existing PA system? Or should the speaker wear a small lapel
microphone for the FM or loop system in addition to using the
existing public address system?
- How large is the room?
- Are several adjacent rooms also going to be using amplification
devices? If so, will this present any interference problems?
- How many people will need amplification? How many have hearing
aids with a T-coil?
- Is technical support available for installing the system properly?
- FM systems may experience interference from nearby radio transmissions.
- Since there are several frequencies that can be used by FM
systems, two FM systems can be used in close proximity as long as
they are using different frequencies.
- Loop systems are also susceptible to interference from radios
and some types of electrical equipment such as metal detectors and
some electric motors.
- FM and loop system transmissions are subject to being "over
heard" and may not be appropriate for areas where the security of
the information must be ensured (e.g. secure agencies, procurement
offices, courtrooms, etc.).
- Infrared systems may not work well in rooms with a large amount
- Infrared systems depend on maintaining the "line of sight" from
the emitter to the receiver.
- If several loop systems are setup near each other, there may be
some spill- over of the signal transmitted to the loop system.