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Desktop
and Portable Computers (1194.26)
Updated: August 1, 2001
Desktop and portable computers (1194.26)
(a) All mechanically operated controls and keys
shall comply 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 covered under this provision?
These provisions cover the keyboards, keypads, and other controls
on desktop and laptop computers that need to be activated during the
normal operation of the system. Examples of controls that are not
located on a keyboard but are still covered include but are not limited
to, on/off switches, reset buttons, unlocking controls for docking
stations, and releases on items such as PCMCIA card slots and drives.
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 typical 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
a hand 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 will meet this provision.
Would the reading of status and diagnostic indicators (e.g., light
emitting diodes (LEDs)) on a desktop computerās front panel be required
to be accessible?
Lights and buttons on control panels which are provided strictly
for troubleshooting are not addressed. However, indicators of normal
operation are covered. For example, the status of "power on" is accompanied
by the sound of a fan, and disk activation is accompanied by the sound
of a disk spinning.
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 up to 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.
Some laptop computers, for example, require two hands to simultaneously
depress buttons on both sides of the laptop to open it, while other
laptops can open when a user moves a single switch on the front.
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.
Back
(b) If a product utilizes touchscreens or touch-operated
controls, an input method shall be provided that complies with ¤1194.23
(k) (1) through (4).
 What
products are covered under this provision?
This provision covers both desktop and portable computers that
use touchscreens or other controls which operate through a personās
touch. 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.
Back
(c) 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 biological feature (e.g., voiceprint) of the user exists
and matches specific criteria. Fortunately, many computer software
manufacturers are aware that voice recognition is a beneficial input
or activation method intended to supplement, not replace, other input
controls such as standard keyboards.
Back
(d) Where provided, at least one of each type of
expansion slots, ports and connectors shall comply with publicly available
industry standards.
What does this provision require?
This provision requires connection points on a computer system
to comply with an industry standard technical specification that is
available to other manufacturers. This assures that the developers
of assistive technology will have access to information concerning
the design of system connections and thus be able to produce products
that can utilize those connections. Examples of publicly available
industry standards may include RS-232, Centronics, SCSI interfaces,
PCMCIA, or USB.
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