Authoring Accessible Source Documents
Documents designed for accessibility ensure correct reading-order allowing documents to re to fit the display when magnification or display size is changed. Microsoft Office, Open Office or Adobe authoring tools can be used to create the source document
- Use the application’s built-in features to encode structural elements like sections, paragraphs, headers/footers, lists, tables, columns etc.
- Do not use TAB, Spacebar and Enter keys for positioning.
- Define and apply styles to format the layout and presentation of content objects. This will ensure correct interpretation of structural attributes to the text blocks (paragraph, list, title, forms, heading etc.)
- Create paragraph styles with inbuilt line spacing before and after a paragraph. Avoid using “Enter key” to create the line space.
- Use standard fonts. Do not use fonts that do not map to Unicode as ligatures will not be interpreted correctly
- Avoid placing text in text-boxes. These are considered floating objects and flow to the bottom of a page when the document is converted into a tagged PDF format, regardless of where they are placed on the page in the source document.
- If text-box is used, then they would need to be manually re-positioned in the tag tree to replicate the visual read order using Adobe Acrobat Professional.
- Avoid placing graphics within “drawing canvas” or “text boxes” as these are floating objects and will automatically float to the bottom of the page when converted to PDF format and will require manual handling using Adobe Acrobat Professional.
- Always include alternative text descriptions for images and non-textual objects that provide information.
- Do not provide text-descriptors for decorative elements. These do not need interpretation by screen readers and can be changed to artifacts from within Acrobat editor.
- Use standard graphics file formats
- Vector graphics like charts consist of multiple graphic and text elements. Group multiple graphic elements into a single image before conversion.
- Do not use images created by word processing drawing tools. Convert them into a single graphic file and then insert them into a document
- Insert images inline with the text. All other text-wrapping styles will convert the image into a floating object within a” drawing canvas”.
- Avoid using watermarks as they are created as floating objects
- Use Heading styles to define sections and subsection as they are used by default to create the Bookmarks in the PDF Document
- Use Column format to layout information in a multi-column format
- Add navigational elements like hyperlinks and bookmarks to the document. Bookmarks can be converted to Table of Contents
- Avoid complex layouts using multiple layers, sidebars, multiple columns and complex tables as these can create a confusing structure requiring tedious manual editing and placement of tags in the tag tree to establish correct reading order.
- Avoid using text boxes for sidebars as float to bottom of the tag hierarchy on the page and will need manual placement
- Do not overuse decorations, background images and overlaying graphics as they require manual conversion into artifacts
- Use “Create Table” feature built into word processors to create data tables
- Format table cells with rule lines. Tables created without rule lines, i.e. table used for visual layout, may not convert gracefully and give unexpected results
- Do not merge and split cells after the table has been created as this will change the reading-order of the cells
- Apply row and column headers to table cells
- Use percentage to set table and cell size. This will allow the table to resize gracefully
- Do not create list by typing numbers or other bullets and using TAB or Spacebar to align the content giving an appearance of a list.
- Use the “list style” built-in to the application. Modify the styles to define the bullets, fonts, spacing and nesting of the list items