Proposal for Definition of Levels

Eric and I worked on a new proposal that attempts to combine all three 
proposals.
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UAAG conformance levels (A, AA, AAA) provide a path for user agent 
developers to improve their product over time and to prioritize new 
features to develop. The three levels of UAAG 2.0 conformance are based 
  on the level (A, AA, or AAA) designations of the more than 100 success 
criteria (i.e., specific requirements). The user agent can conform to a 
level by meeting the success criteria of that level and the levels below 
it.
* Level A conformance: All applicable level A success criteria.
* Level AA conformance: All applicable level A and AA success criteria
* Level AAA conformance: All applicable level A, AA, and AAA success 
criteria.

Factors that were considered in the process of assigning a level to a 
success criterion include:
* severity of impact to the user
* inconvenience to other groups of users with disabilities
* commonality of present implementations
* difficulty of implementation (from deterministic to inferential)
* difficulty of implementation (from minor change to creation of a new
sub-system)

UAAG conformance levels attempt to balance the needs of people with
disabilities with the difficulty the user agent developer could
experience in meeting that need. There are many different types of
disabilities and different types of user agents, so the UAAG level
assigned to a success criterion may not precisely match the definition
of the level in all circumstances. To avoid over-complication, the
various combinations of factors were separated into 3 levels:

Level A success criteria (a) address needs of groups of people with 
disabilities who are blocked from information or accomplishing a task, 
and/or (b) provide solutions that are relatively minor for developers to 
implement or are common in the marketplace.

Level AA success criteria address needs where (a) groups of people with 
disabilities have difficulty accessing information or accomplishing a 
task (including tasks causing excessive fatigue) and/or (b) the 
solutions may be more difficult to implement.

Level AAA success criteria address needs where (a) the solution improves 
accessibility or reduces fatigue for specific groups of people with 
disabilities and/or (b) the solution is very difficult to implement.

Received on Wednesday, 15 May 2013 18:27:59 UTC