---
title: "Detectable Warning Surface"
url: "https://commonwaysystem.org/patterns/elements/detectable-warning-surface/"
id: "ELM-DWS-10"
description: "A textured ground surface, typically a grid of truncated domes, installed at the edge of a curb ramp or platform to alert pedestrians with vision impairments to an approaching street edge or crossing point through underfoot texture."
updated: "2026-09-26"
---

# Detectable Warning Surface

`ELM-DWS-10`

Recommended Element

Detectable Warning Surface

A textured ground surface, typically a grid of truncated domes, installed at the edge of a curb ramp or platform to alert pedestrians with vision impairments to an approaching street edge or crossing point through underfoot texture.

## Why this pattern exists

A curb ramp removes the vertical cue (a step down) that traditionally signaled a street edge to a pedestrian using a cane or with low vision; the detectable warning surface restores that cue through texture instead of height. This pattern exists because it is a baseline accessibility requirement everywhere a curb ramp meets a street, not an optional accessory.

## Key considerations

-   Should be present at every curb ramp and transit platform edge reaching a vehicular way, without exception
-   Color contrast with the surrounding surface improves detectability for pedestrians with low vision, not just those who are fully blind[1]
-   Material must remain detectable underfoot over time; a worn-down or damaged surface fails its purpose even if visually still present

## Related patterns

[Curb Ramp](https://commonwaysystem.org/patterns/elements/curb-ramp.md) (ELM-CRP-03) (required companion element); [Transit Platform](https://commonwaysystem.org/patterns/facilities/transit-platform.md) (FAC-TPL-02) (Facility pattern where this also applies at platform edges)

## References

1.  Legal / regulatory [PROWAG (U.S. Access Board, 2023 final rule; adopted into DOT's ADA regulations effective January 17, 2025), Section R305, "Detectable Warning Surfaces." Dome size, spacing, visual contrast, and placement requirements.](https://www.access-board.gov/prowag/technical.html)