Web Accessibility Guidance for Third Parties

All content posted on Nashville.gov provided by vendors, partners, and other third parties should meet the Web Content Accessibility Guidelines (WCAG) 2.1 Level AA standard.

Please see the full WCAG spec for detailed information about how to meet this standard. For your reference, some general guidance is provided here.

Titles and Headings

Pages and documents should have a unique, descriptive title.
Pages and documents should use headings to break up content and provide waypoints for navigation for users of screen readers or alternative input devices.
Headings should be informative, descriptive, and succinct.
Headings should be in hierarchical order, structured like an outline.

Use plain and clear language.
Keep sentences and paragraphs short.
Use lists where possible to group content.
Avoid jargon.
Acronyms should be avoided when possible. If acronyms are used, spell out the acronym completely the first time it's used.
Use tables for structured data, not page layout.

Choose text color that provides a high level of contrast against the background color. (A ratio of at least 4.5:1 is considered good contrast.)
Avoid using color as the only indicator of meaning. Use additional elements like shapes, textures, or labels.

Avoid images of only text or where the meaning of the image is highly reliant on text in the image.
All meaningful images should have a descriptive alternative text ("alt text").
Alt text should describe the image, its purpose, and its meaning within the context of the other content.
Alt text should be simple but descriptive.
All decorative images not meaningful to the text should be marked as decorative or artifact.

Alt text for complex images or diagrams should express the purpose and function of the image. The alt text does not need to fully describe every data point but should express major trends or highlighted data points.

First, consider if information really needs to be a downloadable document or if it would be better expressed as simple text on a page. If your document is a form, consider using a fillable online form instead.
Documents should be designed to be easily viewable and navigable on a wide variety of devices.
Document design should be simple and straightforward. Documents designed to look like printed media such as a book, magazine, or brochure often don't translate well to different screen sizes and can be difficult to make fully accessible.

Start with an accessible source document. Microsoft Word and InDesign are preferred options for designing the source of PDF documents due to their advanced accessibility features.
PDF documents should contain accessibility tags that define the content areas and allow for proper reading and navigation.
Tags should be applied to documents according to the same WCAG 2.1 AA standard as a typical web page. Follow the guidance on this page related to titles, headings, readability, links, color, images, etc. Use a validation tool that checks against WCAG 2.1 AA like PAC 2026, available for free.
PDF documents should have a proper reading order — content should be read and navigated in the order you intend for it to be read.
Ensure PDF metadata such as title, author, and tags are set.

Use a simple document structure and Word's built-in styles to apply formatting.
Follow the guidance on this page related to titles, headings, readability, links, color, images, etc. Use the Accessibility Assistant in Word to check your document for accessibility.
Add metadata such as title, author, and tags before saving or converting.

Follow the guidance on this page related to titles, headings, readability, links, color, images, etc. Use the Accessibility Assistant in Excel to check your document for accessibility.
Add metadata such as title, author, and tags before saving or converting.
Write unique and descriptive titles for each slide.
Review the reading order of content on each slide.

Follow the guidance on this page related to titles, headings, readability, links, color, images, etc. Use the Accessibility Assistant in PowerPoint to check your document for accessibility.
Provide a unique and descriptive name for each worksheet in the workbook.
Add metadata such as title, author, and tags before saving or converting.
Don't merge cells.
Avoid empty cells. Consider using "N/A" or "no data" instead of an empty cell.
Set row and column headers when appropriate.

All official social media content should follow the same WCAG 2.1 AA guidelines as content provided on Nashville.gov.