Technical / Engineering Plan

Who Is Affected

People who are blind or have low vision, individuals using screen readers, and users who cannot perceive detailed visual information in technical drawings and architectural plans.

What This Means

Technical drawings, engineering plans, architectural blueprints, and site plans are inherently visual documents that contain critical information about construction projects, zoning, infrastructure, and public facilities. When these documents are published as PDFs or images without accessible alternatives, people with visual impairments cannot access essential information about public projects that may affect their community.

These documents often contain complex spatial relationships, measurements, symbols, and technical specifications that require specialized approaches to make accessible. Simply adding alt text is insufficient — you need comprehensive alternative formats that convey the document's purpose and key information.

Fix: Document

Create an accessible alternative that serves the same purpose as the technical drawing:

Option 1: Structured Text Alternative

1. Create a detailed text description that includes:
   • Document purpose and project overview
   • Key measurements and dimensions
   • Location and orientation information
   • Critical features, structures, or systems shown
   • Relevant symbols, legends, or annotations
2. Organize information logically using headings and lists
3. Include essential data such as:
   • Property boundaries and dimensions
   • Utility locations and specifications
   • Access points and circulation paths
   • Elevation changes and grading information

Option 2: Data Tables

For documents with quantifiable information:

1. Extract numerical data into properly structured HTML tables
2. Use clear column and row headers that identify what each measurement represents
3. Group related information (e.g., all electrical specifications in one table)
4. Include units of measurement and reference points

Option 3: Accessible Summary with Contact

For highly complex technical documents:

1. Provide a comprehensive summary covering the document's key purposes and conclusions
2. List critical specifications that affect public access or safety
3. Include contact information for technical staff who can provide additional details
4. Offer alternative consultation methods (phone, email, in-person review)

Implementation Steps

1. Review the original document to identify its primary purpose and audience
2. Determine which information is essential for public understanding
3. Choose the most appropriate alternative format based on document complexity
4. Create the alternative using accessible HTML or Word document formats
5. Link prominently from the original document or provide both versions together
6. Test with screen reader users or accessibility tools to verify usability

Standard Reference

WCAG 2.1 Success Criterion 1.1.1 — Non-text Content, Level A

All non-text content that is presented to the user has a text alternative that serves the equivalent purpose, except for specific situations including complex images that require detailed description.

• W3C Understanding SC 1.1.1
• WCAG Technique G92 — Long description for complex images
• WCAG Technique G73 — Alternative version of content
• WCAG Failure F65 — Missing text alternative
• WCAG Failure F30 — Text alternatives that do not serve equivalent purpose