Clarification of checkpoint 7.4

Ian and I took an action item at the 10 August 2000 telecon to propose a 
clarification of 7.4 based on the discussion on the call [1].

Here is the proposed text:

8. Clarification of checkpoint 7.4
Added: xx August 2000
Type: Clarification
Refers to: Checkpoint 7.4 of 5 May 1999 version
Description (and correction): Checkpoint 7.4 says,
Until user agents provide the ability to stop the refresh, do not create 
periodically auto-refreshing pages. [Priority 2] For example, in HTML, 
don't cause pages to auto-refresh with "HTTP-EQUIV=refresh" until user 
agents allow users to turn off the feature.

This checkpoint is trying to address two issues:

1. Disorientation due to unexpected changes in content. Users should 
expect  changes in content when they follow a link or submit a form. 
However, the author may cause unexpected changes to content by using 
scripts or other markup. The author should inform the user of changes that 
will occur without explicit user interaction.
For example, if pressing a submit button will cause an intermediate page to 
appear before the final results are displayed, inform the user in advance. 
In short, warn the user of what will happen without their explicit interaction.

2. Response time not long enough to interact or comprehend the content 
before it changes.  To ensure that users can interact with and understand 
content in a time frame suitable to their needs, do not cause automatic 
content changes at regular intervals (such as a page of stock quotes that 
is updated every 3 minutes).

There is an "until user agents" clause that is not yet satisfied for this 
checkpoint.  Note that the User Agent Accessibility Guidelines will require 
user agents to provide the ability for users to update pages manually.


wendy a chisholm
world wide web consortium
web accessibility initiative
madison, wi usa
tel: +1 608 663 6346

Received on Friday, 18 August 2000 18:37:43 UTC