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Self
Contained, Closed Products (1194.25)
Updated: August 1, 2001
Self contained, closed products (1194.25)
(a)
Self contained products shall be usable by people with disabilities
without requiring an end-user to attach assistive technology to
the product. Personal headsets for private listening are not assistive
technology.
What are self contained, closed products?
 Self
contained closed products generally have embedded software and
are commonly designed in such a fashion that a user cannot easily
attach or install assistive technology. For example, one could
attach a screen reader to a computer which meets the section 508
standards but one would not be expected to attach a screen reader
to a copier machine. A copier machine is an example of a self-contained,
closed product. Other examples include,  calculators,
fax machines, information transaction machines, and information
kiosks. Unlike other provisions which allow a product to meet
the standards by being compatible with assistive technology, this
provision requires self contained, closed products to contain
built-in accessibility. Although not built-in, a headset is considered
an allowable add-on, since it is not considered assistive technology
in this case. Headsets might be used for privacy, not accessibility
reasons.
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(b) When a timed response is required, the user
shall be alerted and  given
sufficient time to indicate more time is required.
This provision addresses access problems that
can arise when self contained, closed products require a response
from a user within a certain time. For example, persons with dexterity
related disabilities would find entering information such as a
social security number within a specified time difficult or impossible.
This provision requires that a user be notified if a process is
about to time-out and be given an opportunity to answer a prompt
asking whether additional time is needed.
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(c) Where a product utilizes touchscreens or
contact-sensitive controls, an input method shall be provided
that complies with ¤1194.23 (k) (1) through (4).
(1) Controls and keys shall be tactilely discernible without
activating the controls or keys.
(2) Controls and keys shall be operable with one hand and shall
not require tight grasping, pinching, or twisting of the wrist.
The force required to activate controls and keys shall be 5 lbs.
(22.2 N) maximum.
(3) If key repeat is supported, the delay before repeat shall
be adjustable to at least 2 seconds. Key repeat rate shall be
adjustable to 2 seconds per character.
(4) The status of all locking or toggle controls or keys shall
be visually discernible, and discernible either through touch
or sound.
What products are generally covered under this provision?
 This
provision covers products that use touch screens or other controls
which operate through a personās touch. In some instances, a personal
computer with a touch-screen will be enclosed in a display and
used as an "information kiosk". Touchscreens and other controls
that operate by sensing a personās touch pose access problems
for a range of persons with disabilities. This provision does
not prohibit the use of touchscreens and contact sensitive controls,
but requires a redundant set of controls that can be used by persons
who have access problems with touchscreens.
Is the latching mechanism to release a toner cartridge in a
copier considered a control covered by section 508?
No. Changing a toner cartridge is considered maintenance,
not normal daily operations. These provisions apply to operable
controls which are defined as components of a product that require
physical contact for normal operation. Operable controls include,
but are not limited to, mechanically operated controls, input
and output trays, card slots, keyboards, or keypads. These provisions
are intended to apply to products in their normal operation rather
than when a product may be used for maintenance, repair, or occasional
monitoring. Operable controls for tasks such as initial set-up
and configuration, adding and replacing parts, and repair and
service tasks, are not covered by the standards.
Would printer control panels used for configuration, status,
diagnostic, or maintenance functions be required to be accessible?
If a panel of lights were used strictly for troubleshooting,
they would not be addressed by the standards. However, these controls
are usually available for all to use and may be temporarily set
for the tasks of co-workers. Adjustments may be needed for features
in a copier such as contrast, reduction, double sided, stapling,
and sorting. Sometimes, people accidentally hit an exposed button
and the user needs to put the system back on-line. Therefore,
these controls are necessary for normal daily operation and are
required to be accessible.
What is meant by "tactilely discernible"?
Individual keys must be identifiable and distinguishable from
adjacent keys by touch. A product can meet this provision by using
various shapes, spacing, or tactile markings. The normal desktop
computer keyboard, for example, would meet this provision because
the tactile marks on the "j" and "f" keys permit a user to locate
all other keys tactilely. In addition, the physical spacing of
the function, "numpad" and cursor keys make them easy to locate
by touch. Because touch is necessary to discern tactile features,
this provision requires keyboards to enable touch that does not
automatically activate a function based on mere contact. Fortunately,
most keyboards require some pressure on individual keys in order
to enable a keystroke.
However, "capacitance" keyboards would not meet this provision
because they react as soon as they are touched and have no raised
marks or actual keys. They may not react at all when touched by
persons with prostheses. A "membrane" keypad with keys that must
be pressed can be made tactilely discernible by separating keys
with raised ridges so that individual keys can be distinguished
by touch.
What is meant by "status of controls" and why do people need
that information?
This provision requires that the status of toggle controls,
such as the "caps lock" or "scroll lock" keys be identifiable
by either touch or sound, in addition to visual means. For example,
adding audio patterns, such as ascending and descending pitch
tones that indicate when a control is turned on or off, would
alleviate the problem of a person who is blind inadvertently pressing
the locking or toggle controls. Also, buttons which remain depressed
when activated and switched with distinct positions may meet this
provision.
What does "key repeat" mean?
This provision addresses a challenge encountered by some people
with fine motor coordination difficulty. Sometimes, they accidentally
press a key several times when intending to hit it only once.
This could potentially result in the same character displaying
several times on the screen. Some systems do not support key repeat.
However, where key repeat is provided, this provision requires
the repeat to be adjustable. Specifically, the delay must be adjustable
for a length of time that is no greater than 2 seconds between
repeats.
How will individuals with disabilities benefit from the requirement
enabling operability without tight grasping, pinching, twisting,
or pressure?
Individuals with tremor, cerebral palsy, or other disabilities
may have difficulty operating systems which require fine motor
control, a steady hand, or two hands to be used simultaneously
for operation. Individuals with high spinal cord injuries, arthritis,
and other conditions may have difficulty operating controls which
require significant strength. This provision limits the force
required to five pounds and is based on section 4.27.4 of the
ADA
Accessibility Guidelines, codified as the ADA Standards
for Accessible Design as part of the Department of Justiceās regulation
implementing title III of the ADA at 28 C.F.R. pt. 36, Appendix
A. This provision is also consistent with the Telecommunications
Act Accessibility Guidelines.
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(d) When biometric forms of user identification
or control are used, an alternative form of identification or
activation, which does not require the user to possess particular
biological characteristics, shall also be provided.
What are biometric forms of user identification or control?
Biometric controls refer to controls that are activated only
if a particular biol ogical
feature (e.g., voiceprint) of the user exists and matches specific
criteria. Other examples include retinal scans and fingerprint
identification that may become a common practice for allowing
an individual to gain access to personal data from an information
transaction type of machine.
Biometric controls provide a high level of security. However,
when a system needs to be accessed by a person with a disability
and that disability prohibits the use of a specific biometric
feature, a non-biometric alternative should be provided that does
not compromise security.
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(e) When products provide auditory output,
the audio signal shall be provided at a standard signal level
through an industry standard connector that will allow for private
listening. The product must provide the ability to interrupt,
pause, and restart the audio at anytime.
Does this provision apply to "beeps and tones" or to voice
signals only?
This provision applies only to voice output. For example,
it could apply to a device that is providing voice output for
a person who is unable to see a visual display.
What is meant by a standard connector?
People who regularly uses information transaction kiosks may
plan to carry a portable headset (or other listening coupler)
with them. Examples of common plugs on headsets include those
that fit 2.5 mm jacks (such as those in most cellular phones)
and 3.5 mm plugs (such as those in most portable stereos). There
have been problems in the past when manufacturers made proprietary
plugs that were flat with multiple pins and were compatible only
their own products.
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(f)
When products deliver voice output in a public area, incremental
volume control shall be provided with output amplification up
to a level of at least 65 dB. Where the ambient noise level of
the environment is above 45 dB, a volume gain of at least 20 dB
above the ambient level shall be user selectable. A function shall
be provided to automatically reset the volume to the default level
after every use.
How was the level of 65 dB determined?
According to the Occupational Safety and Health Administration,
and the American Speech, Language, and Hearing Association, 65
dB is the volume level for normal speech. This provision requires
that audio output from a kiosk type product have a minimum level
of 65 dB. A feature has been required to automatically reset the
volume to the default level after every use. This is consistent
with a similar provision addressing telecommunications products.
 What
are the needs of people with partial hearing?
People who are hard of hearing, generally speaking, require
voice levels to be 20 dB above the ambient sound level to understand
speech. This means that as long as the noise level in the surrounding
environment is below 45 dB, the 65 dB output level would be sufficient.
If the product is in an environment with a high noise level, the
user must be able to raise the volume to a setting of 20 dB higher
than the ambient noise level. This would require the owner or
other appropriate responsible party to determine the volume of
the background noise at the location of the machine (specifically
whether it is above 45 dB), so the machine can be selected or
calibrated for that specific environment. To effectively meet
this provision, consideration needs to be given to the fact that
ambient noise levels may vary in certain environments.
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(g) Color coding shall not be used as the only
means of conveying information, indicating an action, prompting
a response, or distinguishing a visual element.
How can color coding create accessibility difficulties?
A software program that requires a user to distinguish between
otherwise identical red and blue squares for different functions
(e.g., printing a document versus saving a file) would pose problems
for anyone who was color blind and would generally be very difficult
to run with assistive technology. Screen reading software can
announce color changes. However, this is an "on/off" feature.
This means that if a user had to identify a specific color, they
would have to have all colors announce which would greatly reduce
the usability of the software for that person.
Does the provision prohibit the use of colors?
No. This provision does not prohibit the use of color to enhance
identification of important features. It does, however, require
that some other method of identification, such as text labels,
be combined with the use of color.
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(h) When a product permits a user to adjust
color and contrast settings, a range of color selections capable
of producing a variety of contrast levels shall be provided.
Do all products have to provide color selections?
No. This provision is applied to those products that already
allow a user t o
adjust screen colors.
What is the desired outcome of this requirement?
This provision requires more than just providing color choices.
The available choices must also allow for different levels of
contrast. Many people experience a high degree of sensitivity
to bright displays. People with this condition cannot focus on
a bright screen for long because they will soon be unable to distinguish
individual letters. An overly bright background causes a visual
"white-out". To alleviate this problem, the user must be able
to select a softer background and appropriate foreground colors.
On the other hand, many people with low vision can work most efficiently
when the screen is set with very
sharp contrast settings. Because there is such a variance in individual
needs it is necessary for a program to have a variety of color
and contrast settings.
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(i) Products shall be designed to avoid causing
the screen to flicker with a frequency greater than 2 Hz and lower
than 55 Hz.
Why are flashing or blinking displays limited by this provision?
This requirement is necessary because some individuals with
photosensitive epilepsy can have a seizure triggered by displays
that flicker or flash, particularly if the flash has a high intensity
and is within certain frequency ranges. The 2 Hz limit was chosen
to be consistent with proposed revisions to the ADA Accessibility
Guidelines which, in turn, are being harmonized with the International
Code Council (ICC)/ANSI A117 standard, "Accessible and Usable
Buildings and Facilities", ICC/ANSI A117.1-1998 which references
a 2 Hz limit. An upper limit was identified at 55 Hz.
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(j) Products which are freestanding, non-portable,
and intended to be used in one location and which have operable
controls shall comply with the following:
(1) The position of any operable control shall be determined
with respect to a vertical plane, which is 48 inches in length,
centered on the operable control, and at the maximum protrusion
of the product within the 48 inch length (see Figure 1 of this
part).
(2) Where any operable control is 10 inches or less behind
the reference plane, the height shall be 54 inches maximum and
15 inches minimum above the floor.
(3) Where any operable control is more than 10 inches and not
more than 24 inches behind the reference plane, the height shall
be 46 inches maximum and 15 inches minimum above the floor.
(4) Operable controls shall not be more than 24 inches behind
the reference plane (see Figure 2 of this part).
What do these provisions require?
These provisions apply to the physical characteristics of
large office equipment including reach ranges and the general
physical accessibility of controls and features. Examples of these
products, include but are not limited to copiers, information
kiosks, and free standing printers. These provisions are based
on the Americans
with Disabilities Act Accessibility Guidelines (ADAAG
4.2 Space Allowance and Reach Ranges).
If a document feeder was within the technical specifications,
but access to the platen glass was outside the reach range, would
a copier machine meet the provisions?
No. Users need to be able to access both ways of placing a
piece of paper on a copier for copying. There are some things
(too small or too large) that cannot be run through a paper feed.
If the trays for storing reams of paper are not reachable,
does the copier machine meet the provisions?
Copier paper tray access is not covered under the standards
because replacing paper is considered a maintenance function,
not a normal daily operation. Operable controls include, but are
not limited to, mechanically operated controls, input and output
trays, card slots, keyboards, or keypads. The standards apply
to products in their normal operation rather than when a product
may be used for maintenance, repair, or occasional monitoring.
Other tasks such as initial set-up and configuration, adding and
replacing parts, and repair and service tasks are also not covered
by the standards.
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