Accessibility in practice: WCAG, testing and screen readers

The web accessibility split this section holds to, for disability and content accessibility

There are two accessibility conversations and they get tangled constantly.

One is legal: what Australian law requires, who it applies to, and what exposure a business carries. That lives in website accessibility in Australia, and it is deliberately not repeated here — the Disability Discrimination Act does not need explaining twice.

The other is practical: what you actually build, what you test, and what it costs to fix a site that was not built that way. That is this section.

The split matters because the legal framing tends to swallow the practical one. A business told it has an obligation asks what the minimum is; a business shown what a keyboard-only visitor experiences on its own booking form usually asks a better question.

What these accessibility guidelines cover: colour contrast, alt text and assistive technologies

The ground floor. What accessibility means in practice and who is affected by inaccessible websites — the overlap between vision, hearing, motor and cognitive disability is larger than most people assume, and temporary and situational impairment widens it further. Assistive technologies such as a screen reader, a switch device or voice control sit on top of the same underlying page, so a page built for one assistive technology is usually built for most of them. WCAG conformance levels A, AA and AAA explains what a conformance claim does and does not commit you to, and what “accessibility guidelines” actually means when a supplier cites it.

The build. Colour and contrast, keyboard navigation, headings, landmarks and screen readers, alternative text that is actually useful, forms everyone can complete, video, audio, captions and transcripts, and motion, animation and reduced-motion preferences.

Testing and fixing. What automated scanners can and cannot find is the one to read first if a tool has just given you a score. Then commissioning an accessibility audit, remediating an existing site, and accessibility statements. Testing with an actual screen reader, not just a scanner, is what separates a page that reports clean from a page that is usable.

Where to start with a screen-reader-tested accessibility self-assessment

If you have a site already, start by finding out where it stands. The accessibility self-assessment is a questionnaire you can work through without any technical background, and it produces a list specific enough to hand to a supplier.

If you are commissioning a build, the useful move is to put accessibility in the brief as a requirement with a named conformance level, rather than as an adjective. “Accessible” in a quote means nothing. “WCAG 2.2 Level AA, tested with a keyboard and a screen reader before sign-off” is a thing somebody can be held to.

WCAG 2.2 conformance levels, screen readers and what “accessible” actually tests

WCAG is a W3C technical standard, not a law, and this section treats it as one: a fixed, testable bar independent of which country’s legislation might reference it. Screen reader testing against that bar means using an actual screen reader — NVDA, JAWS or VoiceOver — not just reading the code and guessing what it announces. A site that passes an automated check and has never been opened with a screen reader has not actually been tested against WCAG; it has been tested against the part of WCAG a scanner can see.

One caution about automated scanner accessibility scores

An automated scanner will give a site a number, and the number is close to meaningless on its own. Scanners reliably catch a minority of the criteria — missing alt attributes, contrast failures, absent form labels — and are structurally incapable of judging whether alt text is useful, whether a heading structure describes the page, or whether a keyboard user can actually complete the task. A site can pass a scanner and be unusable.

That is not an argument against scanners. It is an argument for knowing what a passing score covers, which is what the testing pages here are for. For where accessibility sits inside web design as a discipline, start with web design in Australia.