What You Should Know about a Detectable Warning Surface

A detectable warning surface is designed to help Americans with disabilities navigate public spaces and sidewalks safely. These surfaces are useful for those who also use wheelchairs, canes, or mobility aids. Detectable warning surfaces were first mandated by the ADA in 2001. The laws differ slightly by location, but they are required in all public areas where there are also pedestrians present. This can include in trains, bus stations, handicap ramps, curb ramps, and in any other locations where they can be used to prevent injuries.

How It Works

These surfaces alert people that there are going to be changes in the environment. If it’s an intersection or crosswalk, traffic could be ahead or the elevation may be changing. It’s also useful at train or bus stations where someone who is visually impaired may not sense potential danger ahead.

Features to Look For

Selecting the right detectable warning surface is important for a retrofitting project or new construction. You will need to be compliant with ADA requirements.

Location Requirements: ADA requires that warning surfaces be installed on curb ramps, train and rail platform edges, and hazardous crosswalks.

Spacing: The domes that are raised on the warning surface will need to have a minimum spacing of 1.6 inches but no more than 2.4 inches.

Size: The warning system will need to be a series of tactile domes over a square rectangle or radial grid that follows the ADA requirements. The surface needs to be a minimum of 24 inches long in the direction of travel and extend the entire width of the surface it’s being installed on.

Color: There aren’t any specific color requirements, but the surface must contrast with the color of the street platform, sidewalk, or surface where it is being installed.

Types of Products

There are different types of products you can consider, in addition to ADA requirements. A cast-in-place system is a good fit for any new construction projects or retrofitted ones where fresh concrete is being poured. This type of system is embedded into the fresh concrete and then remains there once the concrete has dried. A replaceable cast-in-place system is similar to a cast-in-place system but also has a panel that can be replaced. The two pieces will allow it to be easily changed without having to remove the entire panel that is embedded into the concrete. Surface applied solutions are also suitable for any new construction projects and can be placed over the top of existing surfaces, meaning they can be installed in just about 10 minutes. A radius system is curved for use around corners or others curved areas. Panels for a radius system can be installed in the different ways regular panels are installed.