Universal Accessibility focuses on
the widest possible set of users.
USER Lab is especially concerned with developing methods to analyze,
design, and evaluate systems to improve their universal accessibility.
USER Lab has developed a series of reference models for Accessible
and for Assistive Technologies.
This page includes information on:
The UA project team includes:
- Jim Carter,
- International convenor(chair) and expert member of
ISO/IEC/JTC1/SC35/WG6 User Interface Accessibility
- Canadian expert member of ISO TC159((SC4/WG 5,WG6), (WG2)),
- Lisa Tang
- Accessibility engineering graduate student
- Tanya Lung
- Accessibility engineering graduate student
- Jared Boyko
- Accessibility research assistant
- David Fourney, Associate Member
- Accessibility advocate,
- Canadian expert member of ISO TC 159/SC 4/WG 5, ISO/IEC
Some major UA insights from our team
The Universal Access Reference Model (UARM), as illustrated in
1, concentrates on the interactions between a user and a system.
are anything that may interfere with the accessibility of interactions
users and systems. A handicap may have one or many sources among the
user, interaction, and/or environment. This model is blame-free, since
any handicap is more important than attributing blame to the source of
Figure 1.Universal Access Reference Model (UARM)
The figure uses a pipe metaphor to illustrate the flow of
between the user and the system and a valve metaphor within the pipe to
illustrate various levels of handicaps. A fully open valve represents
absence of a handicap. A fully closed valve represents being fully
Any other setting of the valve represents being partially handicapped.
environment and any context that is shared between the user and the
can effect the flow through the valve in positive and/or negative
Essentially, an AT is a means of opening the valve. ATs reduce
While a consumer of an AT may not have a disability, there is some
of the interaction that is handicapping them. For example, one could
a lecture where the speaker uses a language unknown to the listener.
most people know at least one language, the listener may eventually
to know the language the presentation is given in, but is currently
by not knowing the language at the present time. The listeners task of
the details of the presentation would not be possible without the use
a translator to bridge the interaction between the listener and the
In this sense, the translator would be an AT.
Assistive technologies function to open the valve between systems
users, as illustrated in Figure 2. An AT serves as a proxy within the
between the user and the system by providing contexts compatible to
of the user and the system to perform the translation of specific media
types/channels in each direction. For this reason, AT is not shaped as
box, but as a modified valve. It is hoped the AT becomes an invisible
within the interaction.
Figure 2. Positioning Assistive Technology in the UARM
Our UARM is being used in:
ISO IS 9241-20 Ergonomics of human system interaction-
guideline for information communication equipment and services
Guidelines as a basis for organizaing high level ergonomic
for computer (hardware and software) systems.
ISO 9241-171 Guidance on Software Accessibility in order to
the set of guidance beyond that from ISO TS 16071.
ISO/IEC 24756 Framework for specifying a common access profile
(CAP) of needs and capabilities of users, systems, and their
environments which expands upon the Universal Access
Model to provide for as a basis for describing and evaluating the
needs and issues of users, systems, and environments.
Current Research Directions: Creating Alternative TextAlthough
a picture is worth a thousand words, what might those thousand words
be? Currently, on most web pages, alternative text (alt-text) for
images does not exist. Even when it is available, the description is
often uninformative and limited. This is the result of telling
developers that they need to create alt-text without giving them
sufficient guidance (or even any guidance) on what it should contain.
It is no wonder alt-text is so poorly done. This project involves
efforts to guide developers to create good alt-text.
Guidance on Creating Alternative TextWhile
guidance exists on the technical methods for providing alt-text (such
as the alt and longdesc attributes of the HTML img tag) [2,8], there is
no such guidance on what to include as alt-text. As a result,
developers do not know what to write. Thus, poor and uninformative
descriptions often results. Before developers can write informative
alt-text, they need to know what information is present in the image.
We researched the various recommendations on how images can be describe
within a variety of domains, including: accessibility, information
sciences, and information technology. While many recommendations only
deal with particular types of images, we recognized the need for a
single comprehensive method that couls be applied to all types of
Our research led to the creation of “Guidance on
creating alternative-text for images” that was submitted by the
Standards Council of Canada to ISO/IEC JTC1 Information Technology /
SC35 User Interfaces as the basis of a new standards project.
Tool forHelping Developers Create Alternative TextWe
are currently prototyping a tool that helps developers to apply the
“Guidance on creating alternative-text for images” . We expect that a
public distribution of the tool will be available in Spring 2011.
Current Research Directions: Tools to expand accessiblity
While text is relatively easy to shift modalities (presenting it
visually on displays, auditorially via voice synthesis, or tactilly via
Braille or other tactile symbols) pictures, diagrams, and other
multi-dimensional spaces are still to be made universally accessible.
USERLab currently has a a variety of research projects exploring the
various dimensions of this complex research area, including:
Developing Accessible Development Tools
There is a lack of accessible software development tools tools to
support visually impaired computer professionals. (This is yet
another case of "the shoemaker's children have no shoes.")
Most Software Engineering and Database design tools are highly visual
and graphic. They are generally built with only sighted users in mind
and do not provide information needed to internally visualize the
database being created. This project is investigating
requirements and techniques for making graphical development tools
accessible, regardless of visual capabilities.
Tanya Lung is currently researching the use of auditory and
tactile/haptic interactions in making software development tools
accessibile. This research is an outgrowth of her CMPT 840 project tht
developed DBVisAssist to assist a non-sighted student who was taking a
database course where she was the tutor.
DBVisAssist is a tool which enables auditory-visual diagramming of
Entity-Relationships(ER). DBVisAssist presents tables,
attributes, and relationships to both sighted and non-sighted users in
an understandable and accessible format. Users are able to create
and modify a diagram as well as navigate through a database structure
regardless of their sight capabilities.
With such a tool, visually impaired users can more easily design
databases and understand the database designs by others providing
benefits previously shared by only sighted designers.
Finding Your Way on to a Location That Involves Complex Directions
Locating a classroom for the first time in a large university can be a
major challenge even for fully sigted students. There are often too
many twists, turns, and distances to remember and use along the way.
This poses a significant cognitive load for many people. This problem
is all the more crucial for non-sighted students.
At the same time, most people can learn and recognize the many twists
and turns in a peice of music. This is because of their ability to work
with and internalize rythms. Rythms also apply to navigation. Consider
how most people can get up in the middle of the night and without the
use of lights navigate from their bed either to the toilet or the
refrigerator. While not as complex as finding one's way to most
university classrooms, this can still invovle a number of twists,
turns, and different distances and is often done without having to
consciously think about doing it.
This project is investigating the use of rythms in learning complex
sets of directions for walking to classrooms in a university. It
recognizes that while GPS (global positioning systems) can aid in
navigtion in public spaces, that they are a long way from aiding in
navigating the cooridors of higher learning. This is at least in part
due to the natrue of university buildings where many different
doors and corridors are in very close proximity to each other and where
the characteristics of the buidlings can inhibit getting an accurate
positioning with current technology. This research is also intended to
give the user a sense of how to navigate an unfamiliar space prior to
the first encounter with it.
Jared Boyko is currently researching the use of wii (TM) controlers to
teach people the rythms of how to navigate from one location to another
within a university.
Research into Comparing CapabilitiesDavid
Fourney developed the Common Access Profile (now standardized in
ISO?IEC 24756) to aid in identifying handicaps to accessibility and to
help in identifying assistive technologies that can overcome these
Research into Describing Pictures
Pictures only say a thousand words if you can see them and understand
what you see. With some pictures (including would be illustrative
diagrams in textbooks) seeing is not enough to ensure
understanding. Databases of pictures, even in major art
galleries, tend to have very little data describing the actual pictures
and even less that can be used to support finding pictures that meet a
various user determined sets of criteria. Despite advances in computer
vision, it is not yet feasible
for computers to understand the content and significance of pictures in
a way that can support users. The only way to practically find all the
pictures in a database that meet some visual or conceptual criteria is
to have a sighted person who understands what to look for spend the
time and look at every one of them. While humans are often the most
effective form of assistive technolgy, replying on human assistants to
perform such a task whenever and wherever it occurs is seldome feasible
Understanding the contents and significance of pictures presents
accessibility issues for more than just the visually impaired. While
Alt-text provides a technique for making information on pictures
accessible in Web and other technologies, the problem is having good
information to access. Developers faced with the requirement to provide
Alt-text often just copy the caption of a picture into the Alt-text
field, thus defeating the purpose of requiring Alt-text in the first
place. Automatic Web accssibility evaluators are not able to determine
whether any Alt-text is meaningful or not.
There is a need for developing an approach to describing the contents
of pictures in a meaningful way, that is accessible to both users and
developers. This project is investigating various aspects of this
- describing meaningful objects within a picture, both in terms of
physical object type and attributes and in terms of their semantic
- describing spatial and logical relations between objects within a
- allowing users to obtrain information about a picture and to
navigate between objects within a picture
- aiding developers to use these concepts to develop meaningful
Mr. Alan Wolinski investigated database design for describing
objects and their relationships within a picture. Mr. John Ylioja
investigated methods to support developers in generating textual
representations of imiges. Various other past and current projects in
CMPT 480 / 840 have also contributed to this research area.
Ms. Lisa Tang is now conducting advanced research in this area with
an aim to developing both and ISO/IEC technical report providing
guidance and a software tool to help apply the guidance.
Select UA publications by our team
L. Tang and J. Carter, Alternative Text for Images on the Web, paper proposal for CSUN 2011.
J. Carter and L. Tang, User interface component accessibility — Guidance on creating alternative text for images, submitted to ISO/IEC JTC1/SC35/WG6 by the Canadian Advisory Committee on User Interfaces, of the Standards Council of Canada.
D. Fourney and J. Carter, 2008. The Ongoing Evolution of
Standards to Meet the Needs of the Deaf and Hard of Hearing,
Proceedings of the 2008 Annual Meeting of the Human Factors Society,
New York, NY, USA, pp. 561-565
L. Tang, D. Fourney, F. Huang, and J. Carter, 2008. Secondary Encoding,
Proceedings of the 2008 Annual Meeting of the Human Factors Society,
New York, NY, USA, pp 566-570.
J. Carter and D. Fourney, 2007, Techniques
to Assist in Developing
Accessibility Engineers, Assets'07, Tempe, AZ
D. Fourney and J. Carter, 2007,
I Want My Money! Tactile Access To Automated Banking Machines,
Proceedings of Workshop on Tactile and Haptic Interaction, Tokyo, Japan
D. W. Fourney and J. A. Carter,
2006, Ergonomic Accessibility
Standards, Proceedings of 16th
Interantional Conference on Ergonomics, International Ergonomics
Association, Maastricht, The Netherlands.
D. Fourney and J. Carter, 2006. A
standard method of profiling the
accessibility needs of computer users with vision and hearing
impairments, Proceedings of CVHI 2006 Conference and Workshop
on Assistive Technologies for Vision and Hearing Impairment,
EURO-ASSIST-VHI-4, Kufstein, Austria, July, 6 pages.
D. Fourney and J. Carter, 2006. A
standard method of profiling
accessibility needs (using the CAP), Proceedings Conference on
e-Society 2006, International Association for Development of the
Information Society, Dublin, Ireland, Vol. II, pp. 138-142.
J. Carter, 2006. Temporal
accessibility, Proceedings of the Workshop on Accessible Media,
University of Potsdam, Potsdam, Germany
D. W. Fourney and J. A. Carter, 2006, Ergonomic
Accessibility Standards, Proceedings of 16th Interantional Conference
on Ergonomics, International Ergonomics Association, Maastricht, The
D. Fourney and J. Carter, 2006, The
International Standsrds for Accessible
Software, Proceedings of the CSUN 2006 Technology and Persons with
Disabilities Conference, Los Angeles, CA.
J. Carter and D. Fourney, 2005, A Common Accessibility Profile for
Selecting and Using Assistive Technologies, manuscript in production.
J. Carter and D. Fourney, 2003, Using an Universal Access Reference
Model to Identify Further Guidance that Belongs in ISO 16071, Universal
in the Information Society, 31(1) 17-29.
J. Carter and D. Fourney, 2003, The Canadian Position Regarding
the Evolution of ISO TS 16071 Towards Becoming and International
Standard, ISO TC159/SC4/WG5 document N0731.
Classes we offer relating to UA
Please note: This page does not use fancy frames or tables and all
are fully explained in order to increase accessibility by individuals