What are Detectable Warnings?Posted on - Monday, February 4th, 2019
Detectable warnings are only required at curb ramps located in the public right of way and platform boarding edges.
Detectable warnings are used to assist persons that are visually impaired in detecting hazards along their wayfinding. A person who is visually impaired uses a sense of touch to find their way. Detectable warnings is one of those methods. In the 1991 ADAAG, detectable warnings were described as having contrasting color and texture. Contrasting color meant that it should have a different color than its surroundings (either light to dark or dark to light) and texture was achieved by using truncated domes. They were required at curb ramps and the edges between pedestrian and vehicular ways.
But in the 2010 ADA Standards they were limited to only platform boarding edges. The Public Right of Way Accessible Guidelines (PROWAG) and the 2012 Texas Accessibility Standards (TAS) also requires detectable warnings at curb ramps located within the public right of way.
This blog will give you the required regulations governing detectable warnings
Platform Boarding Edges
The ADA standards requires that detectable warnings be located along the boarding edges of trains or bus platforms.
ADA 705.2 (train) Platform Edges. Detectable warning surfaces at platform boarding edges shall be 24 inches (610 mm) wide and shall extend the full length of the public use areas of the platform.
ADA 810.5.2 (Bus) Detectable Warnings. Platform boarding edges not protected by platform screens or guards shall have detectable warnings complying with 705 along the full length of the public use area of the platform.
Public Rights of Way
There are also requirements for public rights of way (located outside the property line). The federal standards are called the “Public Right of Way Accessibility Guidelines” (PROWAG). These are still a draft and have not been adopted, although they are recommended. In Texas, TDLR wrote in their administrative rules a set of guidelines for public rights of way. Below is a brief summary of each.
R208 Detectable Warning Surfaces
R208.1 Where Required. Detectable warning surfaces complying with R305 shall be provided at the
following locations on pedestrian access routes and at transit stops:
1. Curb ramps and blended transitions at pedestrian street crossings;
2. Pedestrian refuge islands;
3. Pedestrian at-grade rail crossings not located within a street or highway;
4. Boarding platforms at transit stops for buses and rail vehicles where the edges of the boarding platform are not protected by screens or guards; and
5. Boarding and alighting areas at sidewalk or street level transit stops for rail vehicles where the side of the boarding and alighting areas facing the rail vehicles is not protected by screens or guards.
– Detectable warning surfaces shall extend 610 mm (2.0 ft) minimum in the direction of
– At curb ramps and blended transitions, detectable warning surfaces shall extend
the full width of the ramp run (excluding any flared sides), blended transition or turning space.
– At pedestrian at-grade rail crossings not located within a street or highway, detectable warnings shall extend the full width of the crossing.
– At boarding platforms for buses and rail vehicles, detectable warning surfaces shall extend the full length of the public use areas of the platform.
– At boarding and alighting areas at sidewalk or street level transit stops for rail vehicles, detectable warning surfaces shall extend the full length of the transit stop.
R305.2 Placement. The placement of detectable warning surfaces shall comply with R305.2.
R305.2.3 Blended Transitions. On blended transitions, detectable warning surfaces shall be
placed at the back of curb. Where raised pedestrian street crossings, depressed corners, or other
level pedestrian street crossings are provided, detectable warning surfaces shall be placed at the
flush transition between the street and the sidewalk.
R305.2.4 Pedestrian Refuge Islands. At cut-through pedestrian refuge islands, detectable warning
surfaces shall be placed at the edges of the pedestrian island and shall be separated by a 610 mm
(2.0 ft) minimum length of the surface without detectable warnings
TDLR AB Rules requires:
These requirements are not located in the Texas Accessibility Standards, but rather in the TDLR Administrative Rules Chapter 68
68.102. Public Right-of-Ways Projects
(2) Curb Ramps-
(A) At perpendicular curb ramps constructed within the public right of way, detectable warnings complying with TAS 705 at a minimum of 24″ in depth (in the direction of pedestrian travel) and extending the full width of the curb ramp shall be provided where the pedestrian access route enters a crosswalk or other hazardous vehicular area.
(C) At diagonal curb ramps constructed within the public right-of-way, detectable warnings complying with TAS 705 at a minimum of 24″ in depth (in the direction of pedestrian travel) and extending the full width of the curb ramp or landing, shall be provided where the pedestrian access route enters a crosswalk or other hazardous vehicular area. Additionally, the department will allow the detectable warning to be curved with the radius of the corner.
The detectable warning shall be located so that the edge nearest the curb line is 6″ minimum and 10″ maximum from the curb line.
For more information about PROWAG and its requirements click on this link
TABS (Texas Architectural Barriers online System)
If you do work in Texas you should be aware that there is a new system for online registration and keeping track of the projects. The Texas Department of Licensing and Regulation has now created a system that eliminates most paper forms and makes many things cloud-based.
The main differences are as follows:
1) In order to register a project, you will have to create an account with TDLR here
2) The TDLR registration occurs in the pull-down menu shown below. You can also fill out the registration form and send it to your RAS for her to do it for you.
4) when you register the project (or fill out the registration form), you will also be required to submit the square footage of the building. If it is not a building, make your best faith effort to estimate it.
5) Once you register the project you will be able to view results and other saved items in the online “file cabinet”
In this new system you will be able to update information to the project, upload revised drawings, and check the status of the project.
If you have any questions about this new system you can reach our office or TDLR directly.