The Hidden Complexity of Math and Science: Strategies for making complex STEM journals compliant with WCAG 2.1 Level AA.

Why Math and Science Journals Face Unique Accessibility Challenges

STEM journals rely on equations, graphs, reaction schemes, and data tables to communicate precise ideas. These elements go far beyond plain text, creating barriers for readers who use screen readers, need high contrast, or view content on small screens. Standard web accessibility practices often assume linear prose, leaving the layered, two-dimensional nature of scientific content unaddressed. Publishers who ignore these differences risk excluding researchers, students, and professionals with disabilities while falling short of emerging legal expectations.

WCAG 2.1 Level AA sets clear, testable requirements that directly affect STEM material. Success criterion 1.1.1 demands text alternatives for non-text content. Criterion 1.3.1 requires that structure and relationships remain programmatically available. Criteria 1.4.3 and 1.4.11 address minimum contrast for text and graphical objects. Criterion 1.4.10 ensures content reflows without loss of meaning at narrow widths. Meeting these criteria demands more than cosmetic fixes; it requires rethinking how scientific information is encoded and presented.

Core Strategies for Accessible Equations

Equations form the backbone of most STEM articles. Rendering them as static images fails basic accessibility tests because screen readers cannot parse internal structure. The reliable solution uses MathML, an XML-based markup that encodes both presentation and meaning. Screen readers such as NVDA, JAWS, and VoiceOver can then read equations aloud and let users navigate through fractions, subscripts, or matrices element by element.

Authors typically submit content in LaTeX. Publishers can convert this source directly to HTML containing embedded MathML using tools like Pandoc, LaTeXML, or MathJax. MathJax renders the visual display while preserving the underlying accessible code. This approach satisfies WCAG 1.1.1 and 1.3.1 because the relationships within each expression become machine-readable. Journals that have adopted native MathML report significantly better experiences for blind and low-vision users who no longer need to guess at incomplete alt text.

For legacy PDFs, newer standards like PDF/UA-2 now support embedded MathML, offering a path forward for archival content. However, HTML-first or EPUB workflows deliver superior reflow and keyboard navigation, making them preferable for new publications.

Handling Complex Diagrams and Charts

Scientific figures often convey multiple data series, spatial relationships, or chemical structures that a single short description cannot capture. Follow a layered strategy:

• Write concise alt text that states the figure’s purpose and type.

• Provide a longer, detailed description. The description should cover scales, trends, key values, and relationships.

• Supply the underlying data in a structured HTML table so users can explore numbers independently.

• Use patterns, shapes, or labels alongside color to differentiate elements, meeting non-text contrast requirements.

The W3C recommends placing long descriptions in the main content flow or associating them structurally with the image. This technique ensures equivalent information reaches every reader without forcing screen-reader users to listen to overly long alt attributes. For reaction schemes or vector diagrams, reference source data tables explicitly, so the logic remains traceable.

Making Data Tables Usable and Compliant

Large tables with merged cells, scientific notation, or multi-level headers frequently break screen-reader navigation. Apply these fixes:

• Use proper elements with scope attributes to link headers to data cells.

• Avoid or clearly explain merged cells.

• Add a short summary in surrounding text that explains the table’s purpose. 

• Offer a downloadable CSV alongside the HTML version for users who prefer external analysis tools.

These steps align with WCAG 1.3.1 and improve usability for everyone, including readers on mobile devices who need content to reflow cleanly.

Building Sustainable Workflows at Journal Scale

Compliance works best when built into production rather than added later. Update author guidelines to encourage LaTeX submissions optimized for conversion. Integrate automated pipelines that generate compliant HTML from JATS XML. Test regularly with actual assistive technologies and involve users with disabilities in manual reviews. Automated scanners catch obvious errors, but human judgment reveals whether descriptions truly convey meaning or whether spatial arrangements in equations survive reflow.

Many publishers now combine these practices with EPUB3 output, which supports reflowable text, MathML, and customizable reading experiences. The result reduces remediation costs and prepares content for future standards. Explore our NINJA ePub Accelerator and learn how we can help.

Legal and Practical Benefits

The U.S. Department of Justice’s 2024 ADA Title II rule requires public institutions to meet WCAG 2.1 Level AA by April 2026 for larger entities and 2027 for smaller ones. Universities and research bodies increasingly demand accessible materials from publishers to fulfill their own obligations. Beyond compliance, inclusive journals expand their audience. A blind chemist can follow reaction mechanisms step by step. A low-vision physicist can enlarge graphs without losing detail. The entire community gains when knowledge flows without artificial barriers.

Challenges persist. Some WCAG criteria require careful interpretation for inherently spatial STEM content, such as preserving meaning during reflow of displayed equations. Ongoing work in the accessibility community, including semantic enrichment of MathML, continues to refine solutions.

Moving Forward with Confidence

Publishers who treat accessibility as core infrastructure rather than an afterthought produce higher-quality content for all readers. The hidden complexity of math and science becomes visible and navigable when proper markup, descriptions, and testing replace shortcuts. The tools and techniques exist today. The decision to implement them determines whether scientific publishing remains open to every mind capable of understanding it. At S4Carlisle, we work closely with leading journal publishers to help simplify the process of translating an author’s thoughts to the final journal or book.

Additional Reading

• Web Content Accessibility Guidelines (WCAG) 2.1 – https://www.w3.org/TR/WCAG21/

• Guidance for Making Mathematics Accessible Online, American Mathematical Society – https://www.ams.org/accessibility/accessibility-guidance

• Complex Images, W3C Web Accessibility Initiative – https://www.w3.org/WAI/tutorials/images/complex/ 

• WCAG 2.1 Meets STEM: Application, Interpretation, and Opportunities, Jason White – https://repository.rit.edu/jsesd/vol22/iss1/9/