The Web Content Accessibility Guidelines 2.0

SC	Description
1.1.1	Non-text Content: All non-text content that is presented to the user has a text alternative that serves the equivalent purpose, except for the situations listed below. (Level A)
1.4.1	1.4.1 Use of Color: Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element. (Level A)
1.4.3	Contrast (Minimum): The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following: (Level AA) Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 3:1; Incidental: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement. Logotypes: Text that is part of a logo or brand name has no minimum contrast requirement.
1.4.5	Images of Text: If the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text except for the following: (Level AA)
2.1.1	Keyboard: All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user’s movement and not just the endpoints. (Level A)

The relevant guidelines are detailed in the website manager factsheet.

WCAG 2.0 Sufficient Techniques

For each of the guidelines and success criteria in WCAG 2.0 there are a wide variety of techniques. The techniques fall into two categories:

Sufficient techniques – techniques or a combination of techniques that are sufficient for meeting the success criteria.

Advisory techniques – techniques that should be considered (where relevant) to make content more accessible.The advisory techniques go beyond what is required by the individual success criteria and are not covered by these factsheets.

SC	Description
1.1.1	Situation A: If a short description can serve the same purpose and present the same information as the non-text content:G94: Providing short text alternative for non-text content that serves the same purpose and presents the same information as the non-text content using a short text alternative technique listed belowSituation B: If a short description can not serve the same purpose and present the same information as the non-text content (e.g., a chart or diagram):G95: Providing short text alternatives that provide a brief description of the non-text content using a short text alternative technique listed below AND one of the following techniques for long description: G92: Providing long description for non-text content that serves the same purpose and presents the same information using a long text alternative technique listed below G74: Providing a long description in text near the non-text content, with a reference to the location of the long description in the short description G73: Providing a long description in another location with a link to it that is immediately adjacent to the non-text content Situation F: If the non-text content should be ignored by assistive technology:Implementing or marking the non-text content so that it will be ignored by assistive technology using one of the technology-specific techniques listed below H67: Using null alt text and no title attribute on img elements for images that AT should ignore (HTML) C9: Using CSS to include decorative images (CSS)
1.4.1	Situation B: If color is used within an image to convey information: G111: Using color and pattern G14: Ensuring that information conveyed by color differences is also available in text
1.4.5	C30: Using CSS to replace text with images of text and providing user interface controls to switch (CSS)
2.1.1	G202: Ensuring keyboard control for all functionality

WCAG 2.0 Common Failures

SC 1.1.1 Non-text Content

The following are common mistakes that are considered failures of Success Criterion 1.1.1 by the WCAG Working Group.

Failure	Description
F30	Failure of Success Criterion 1.1.1 and 1.2.1 due to using text alternatives that are not alternatives (e.g., filenames or placeholder text)
F20:	Failure of Success Criterion 1.1.1 and 4.1.2 due to not updating text alternatives when changes to non-text content occur
F3:	Failure of Success Criterion 1.1.1 due to using CSS to include images that convey important information
F39:	Failure of Success Criterion 1.1.1 due to providing a text alternative that is not null (e.g., alt=”spacer” or alt=”image”) for images that should be ignored by assistive technology
F38	Failure of Success Criterion 1.1.1 due to omitting the alt-attribute for non-text content used for decorative purposes only in HTML
F71:	Failure of Success Criterion 1.1.1 due to using text look-alikes to represent text without providing a text alternative
F72	Failure of Success Criterion 1.1.1 due to using ASCII art without providing a text alternative
F65:	Failure of Success Criterion 1.1.1 due to omitting the alt attribute on img elements, area elements, and input elements of type “image”
F67:	Failure of Success Criterion 1.1.1 and 1.2.1 due to providing long descriptions for non-text content that does not serve the same purpose or does not present the same information
F13:	Failure of Success Criterion 1.1.1 and 1.4.1 due to having a text alternative that does not include information that is conveyed by color differences in the image

SC 1.4.1 Use of Color

The following are common mistakes that are considered failures of Success Criterion 1.4.1 by the WCAG Working Group.

Failure	Description
F13:	Failure of Success Criterion 1.1.1 and 1.4.1 due to having a text alternative that does not include information that is conveyed by color differences in the image
F73:	Failure of Success Criterion 1.4.1 due to creating links that are not visually evident without color vision

SC 1.4.5 Images of Text

There are no common failures 1.4.5 currently documented for Success Criterion in WCAG2.0.

SC 2.1.1 Keyboard

The following are common mistakes that are considered failures of Success Criterion 2.1.1 by the WCAG Working Group.

Failure	Description
F54:	Failure of Success Criterion 2.1.1 due to using only pointing-device-specific event handlers (including gesture) for a function