Review of look-alike frameworks

Why it matters

The CPACC exam’s highest-yield confusable in Domain 2 is the three parallel accessibility frameworks: WCAG’s POUR principles, the seven universal design principles, and UDL’s three principles. All three address how to serve diverse users — but they differ in scope, origin, number of components, and application domain. Mixing them up is a very common exam error. (BoK p. 40)

The three frameworks at a glance

	WCAG (POUR)	Seven UD Principles	UDL Three Principles
Developed by	W3C / WAI	Ron Mace, NCSU (1997)	CAST
Count	4	7	3
Applies to	Web content and ICT	Physical environments and products	Educational curriculum and instruction
Primary audience	Web developers, ICT	Architects, product designers	Educators, curriculum designers
Principles	Perceivable, Operable, Understandable, Robust	Equitable, Flexible, Simple, Perceptible, Tolerant, Low Effort, Size/Space	Engagement, Representation, Action & Expression

WCAG: four POUR principles

WCAG organizes all web accessibility success criteria under four principles: (BoK p. 40)

1. Perceivable — content must be presentable through senses users can access.
2. Operable — users must be able to operate all interface components.
3. Understandable — content and UI must be understandable.
4. Robust — content must be interpretable by current and future AT.

WCAG is a technical standard with testable success criteria and conformance levels (A, AA, AAA). It does not apply to physical spaces or educational curriculum — it applies to web content and ICT.

Seven universal design principles

The UD principles provide criteria for evaluating and guiding design of physical environments and products: (BoK p. 42)

1. Equitable Use
2. Flexibility in Use
3. Simple and Intuitive Use
4. Perceptible Information
5. Tolerance for Error
6. Low Physical Effort
7. Size and Space for Approach and Use

The seven UD principles are not a technical standard — they are evaluative guidelines. There are no conformance levels or testable success criteria. They apply primarily to architecture and product design, though they are also applied to digital environments.

UDL: three principles

UDL organizes learning design around three principles aligned with brain networks: (BoK p. 44)

1. Multiple means of engagement — the WHY: motivation, persistence, self-regulation.
2. Multiple means of representation — the WHAT: perception, language, comprehension.
3. Multiple means of action and expression — the HOW: physical access, expression, executive function.

UDL applies specifically to educational settings — curriculum, instruction, and assessment. It is not used to evaluate buildings, websites, or consumer products.

Sorting exercise: which framework?

Concept	Framework
Perceivable	WCAG
Perceptible Information	UD 7 principles
Engagement	UDL
Equitable Use	UD 7 principles
Robust	WCAG
Tolerance for Error	UD 7 principles
Representation	UDL
Operable	WCAG
Action and Expression	UDL
Flexibility in Use	UD 7 principles
Understandable	WCAG
Simple and Intuitive Use	UD 7 principles

Real-world example

A museum is redesigning its permanent collection experience. The design team reviews all three frameworks: WCAG applies to the digital audio guide app (Perceivable = captions for video; Operable = keyboard access; Understandable = plain language; Robust = AT compatibility). The seven UD principles apply to the physical gallery layout (Equitable Use = same entrance for all; Low Physical Effort = wide, level paths; Size and Space = adequate turning radius for wheelchairs). UDL applies to the educational programming (Engagement = choice in how visitors explore; Representation = text labels + audio + tactile models; Action and Expression = multiple ways to respond to exhibits). All three frameworks are relevant — each in its own domain.