W3C home > Mailing lists > Public > w3c-wai-ig@w3.org > October to December 1999

Scott's Chemistry Application

From: Kynn Bartlett <kynn-hwg@idyllmtn.com>
Date: Tue, 26 Oct 1999 15:19:09 -0700
Message-Id: <>
To: Scott Luebking <phoenixl@netcom.com>
Cc: W3c-wai-ig@w3.org
At 02:11 PM 10/26/1999 -0700, Scott Luebking wrote:
>PS  I've been working on a web-based system using sound navigation to
>help teach blind chemistry students about different chemical models.  It
>works with IE4/5 and JAWS, but relies on IE 4/5 features.  Is it
>accessible or not?

Something is accessible if it can be used by users with disabilities.
This is can be used by those users -- therefore it is accessible to

For every thing we put up, there are two sets.  If I could draw reliable
diagrams I would graph it.  In one set we have "all possible users of this
application."  A smaller subset of that group is "users of this application
who can't use it."

(  users     ( who can't use it )    )

Our goal is to reduce the smaller set to nothingness.  When we talk about
making something more accessible, we are really talking about shrinking
that smaller group.  A change which decreases that group by any amount
makes the application more accessible.

If we are talking about the Internet as a whole, we have:

GROUP 1:  Potential Users

Group 1 includes everyone with access to something that can speak
HTTP and retrieve our web pages.  This is a big group.

GROUP 2:  Users who can't use our Internet web page

The size of group 2 depends on how we have created our application.
Our goal is to minimize this subset of Group 1.

By my way of thinking, we are NEVER going to be able to have "perfect
accessibility" within the group of Group 1 -- that would mean that
Group 2 becomes nothing, and that's not reasonable over a set of
180 million users.  Our goal instead is to MINIMIZE the size of Group
2 by making it usable by as many people as possible.

Now, let's look at an intranet:

GROUP 1:  Potential Users

The people in our company.  This is a finite number, be it 8 or 800.

GROUP 2:  Users who can't use our intranet application

This is a subset of the number above.  We _can_ achieve this goal,
because we can control what browsers are used, and we can find the
small(er) number of users with disabilities and design valid
workaround for all of them.

Finally, let's look at your chemistry application:

GROUP 1:  Potential users

Blind students of chemistry.

GROUP 2:  Users who can't use the chemistry program

Well, if you do it right, they can all use it. So the size of this
set becomes zero.

Therefore, over the group of your users, the application _is_

Kynn Bartlett <kynn@hwg.org>
President, Governing Board Member
HTML Writers Guild <URL:http://www.hwg.org>
Director, Accessible Web Authoring Resources and Education Center
Received on Tuesday, 26 October 1999 18:29:26 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 13 October 2015 16:21:06 UTC