What is the required contrast ratio for ADA signs?
Quick Answer
ADA requires a minimum 70% contrast ratio between characters and background on tactile signs. This is measured using light reflectance values (LRV) and applies to both raised characters and the sign background.
Content Verification
Sources:
Code Reference
ADA 703.5
ADA 2010 Standards Section 703.5
Detailed Explanation
Contrast requirements ensure signs are readable by people with low vision:
1. **70% Minimum**: The light reflectance value (LRV) difference between characters and background must be at least 70%.
2. **Calculation**: Contrast = [(B1 - B2) / B1] × 100, where B1 is the lighter surface and B2 is the darker surface.
3. **Common Compliant Combinations**: White on navy blue (85%), black on white (80%), white on black (80%).
4. **Avoid**: Low-contrast combinations like gray on gray, or colored text on colored backgrounds with similar LRV values.
5. **Finish**: Both matte and eggshell finishes are acceptable; avoid high-gloss which can cause glare.
Common Mistakes
- ×Using decorative color combinations with insufficient contrast
- ×High-gloss finishes that cause glare
- ×Colored backgrounds reducing contrast below 70%
- ×Not testing LRV values before production
How to Verify Compliance
- ✓Request LRV values from sign manufacturer
- ✓Calculate contrast using the LRV formula
- ✓Verify 70% minimum contrast
- ✓Check for non-glare finish
Official Code Text
"Characters and their background shall have a non-glare finish. Characters shall contrast with their background with either light characters on a dark background or dark characters on a light background."
How to Cite This Page
When referencing this information:
SpecCodes.com "What is the required contrast ratio for ADA signs?" - Verified 2026-01-30Compliant Products
To meet these requirements, compliant signage typically includes:
Related Questions
Expert Verification
Compliance Information Verified
2026-01-30
CBC 2025 / ADA 2010
Effective January 1, 2026
California Building Standards Commission
Compliance Verification Notice
This information is provided for general reference purposes only. Local inspectors and authorities having jurisdiction (AHJ) have final authority over code interpretation and enforcement.
Before ordering signage, SpecCodes recommends:
- Contacting your local Building Department
- Reviewing current permit requirements for your project
- Confirming any local code amendments that may apply
Legal Notice: This content does not constitute legal advice. SpecCodes provides compliance information as a reference resource only. Users are responsible for verifying all requirements with their local jurisdiction before installation.