Consider closed functionality when adding new clauses
What is closed functionality?
“Closed functionality” is defined in EN301549 as
“functionality that is limited by characteristics that prevent a user from attaching, installing or using assistive technology”.
Here are a few examples of closed functionality:
- When screen reader software cannot be used. This can happen, for example, when the content is presented using specialized or restricted hardware (eg. terminal equipment for use in public environments) offering no way for users to install or connect screen reader software.
- When accessibility features – such as text enlargement, enhanced contrast, reduced motion – in the operating system cannot be used. This can happen, for example, when the application is designed not to adhere to system settings (hopefully because it provides even better accessibility features on its own). Or when there are limitations in the app platform or the accessibility API.
- When an app – perhaps for security reasons – does not expose content and functions to the accessibility API of the platform.
How does EN301549 deal with closed functionality?
Clause 5.1 of the standard contains relatively generic requirements that can be applied when closed functionality makes it inappropriate to apply other, more specific requirements (such as the ones mirroring success criteria from WCAG). For software applications, in clauses 11.1 to 11.4, some requirements have different versions (subclauses) for open and closed functionality. For open functionality, the subclauses generally reference WCAG success criteria and for closed functionality, the subclauses generally reference clauses under 5.1.
A hands-on example:
- Open functionality: Apps that support access to enlargement features of the platform or assistive technology are required (by clause 11.1.4.4.1) to meet WCAG SC 1.4.4 about text resizing (to 200%).
- Closed functionality: Apps that do not have access to such enlargement features are required (by clause 11.1.4.4.2) to instead meet clause 5.1.4, which provides a formula for calculating a minimum text size that must be offered to users.
NOTE 1: Separate clauses for closed functionality have been designed with regard to the nature of the closed functionality. So there are no clauses in section 11 that should be applied broadly for ANY kind of closed functionality. Most of the closed functionality clauses in section 11 are designed for apps with functionality closed for screen reading, and explicitly say so. Any clause should state for what kind of closed functionality it is relevant. (In at least one case, such a statement is missing, by accident.)
NOTE 2: If a software application meets all of clause 5.1, a whole range consisting of 16 clauses (11.5.2 – 11.5.2.17) are explicitly exempted (See clause 11.5.1: “Where the closed functionality of software conforms to clause 5.1 (Closed functionality) it shall not be required to conform with clause 11.5.2 to clause 11.5.2.17.”).
In the context of the Web Accessibility Directive (WAD), table A.2 indicates what clauses in the EN standard should be applied for mobile applications. Ten (10) of those only apply when there’s closed functionality and 16 of them only when functionality is open.
For example, table A.2 contains:
- Clause 11.1.1.1.1, which mirrors WCAG SC 1.1.1 for user interfaces with open functionality.
- Clause 11.1.1.1.2, which provides similar accessibility for user interfaces closed to assistive technologies for screen reading – by referencing a requirement under clause 5.1 (specifically 5.1.3.6 Speech output for non-text content).
WCAG still has “web content” in its acronym in version 2.2, but the EN standard is relevant for more than “web content” and outside of the WAD context of websites and apps belonging to public sector bodies. Clause 8 Hardware, for example, includes all of clause 5. So any changes to clauses 5.1 Closed functionality (or 5.3 Biometrics) must be applicable to a range of other situations. Eg. ATMs for cash withdrawal, public terminals for tickets in airports, non-web based email applications, et cetera.
How does closed functionality apply to the proposed new SC from WCAG 2.2?
For any new clause added to the EN, determine if it must be applied in a special (more generic) way if there is closed functionality. And if so, make appropriate modifications to section 11 and possibly even to section 5.
Predicting all and every possible kind of closed functionality, and how to deal with it, is not easy. Please open up a discussion around this issue for every proposed new clause, in order to collect comments from people with a variety of different perspectives!