MIT strives to adhere to the WCAG 2.1 AA standards for all digital content and encourages DSL content creators to keep accessibility in mind when adding new content to our site. The DAS Digital Accessibility team is happy to support DSL content creators in ensuring that our pages will reach the widest possible audience with minimal barriers. Feel free to contact accessibility@mit.edu with your digital accessibility questions or to schedule a consultation.
Captions
All videos should be captioned. Captions benefit many users including people who identify as d/Deaf or hard of hearing, people who are working in environments where audio is not available, and those for whom reading aids comprehension.
Auto captions are not sufficient, as they do not meet ADA requirements. Captions must be accurate and synchronized with the video. Any podcasts or audio-only files should include a transcript. More information on ways to get your video captioned can be found on MIT’s central Accessibility website.
Heading structure
Headings serve to describe content that follows, similar to the headline of an article. Heading tags (<h1> – <h6>) can make the site more navigable to users of assistive technology like screen readers. Using heading structure properly ensures that our users can access information efficiently. Pages that are well structured and that follow proper syntax are most accessible.
Headings should be nested in order, such that they describe descending degrees of virtual indentation. Heading levels should not be skipped. See the sample tree below:
<h1> This is the main idea of the page
<h2> These are the major themes within the page, followed by body text
<h3> These are sub-themes following the <h2>s
<h2> You can have multiple instances of each heading level as long as they are in descending order and introduce a theme of equal “weight” as the previous headings of that level.
Images and alt text
All images should contain alt text. Images that convey information should contain brief alt text to describe the takeaway. Images that are decorative in nature (in other words, images that do not convey unique information to the user) should be marked as decorative or given null alt text (alt=””).
Writing alt text is more art than science. It is typically best for the content creator to describe the image since they have the best understanding of what they want to convey. Resources such as this Guide to Alt Text Across Popular Tools can help get you started. If you would like to talk through composing your alt text, feel free to contact accessibility@mit.edu for guidance and/or feedback.
Link language
Our sites contain many links to internal pages, external websites, and documents. Hyperlinked text should be both concise and descriptive (think word or words, not sentences). Avoid link language such as “click here,” “learn more,” and “website” and instead, choose link text that describes the target.
Consistency is helpful for all users. By convention, it is typical for links that target pages within the website to open within the current tab. Links to external sites (including other departments within MIT but external to DSL) should open in a new tab.
PDFs
PDFs pose many barriers to accessibility. Because they are, by nature, fixed in format, it can be difficult and time consuming to remediate PDF documents for accessibility. Original file formats (such as Microsoft Word) are typically easier to remediate for accessibility than PDFs, as converting to PDF removes accessibility features, requiring additional remediation.
Content should, whenever possible, be in HTML format to reach the largest possible user base.
If you determine that PDF is the only format that will work for your content, DAS can recommend remediation services to produce accessible PDF versions of your content. Please reach out to accessibility@mit.edu for more information.
Use of color
Color should never be the only means of conveying information. To ensure that visitors will be able to access our content, choose colors where the contrast ratios between text elements and background meet WCAG 2.1 AA contrast standards (at least 4.5:1 for standard text and at least 3:1 for large scale text of at least 18pt/24px or at least 14pt/18.5px AND bold).
Free checkers like the TPGi Colour Contrast Analyser can be used to measure color values and help you determine whether contrast ratios fall within an appropriate range.
Using the automated accessibility checker
Content creators can use the built-in accessibility checker tool to highlight barriers within your pages. While this information can be very helpful in identifying some barriers to accessibility, no automated checker is fully comprehensive and we should habitually manually test added content for accessibility.
The DAS Digital Accessibility team is available to test new content and help you interpret the findings of the automated testing tool as needed. Please reach out to us at accessibility@mit.edu with your questions or to schedule a consultation.