The American Association of State Highway and Transportation Officials (AASHTO) specifies many aspect of highway design and construction in the United States, as well as standards related to all modes of travel.
The AASHTO provides a section, AASHTO M 333-16 (2020), specifying the use of detectable warnings. Accordingly, truncated dome tiles, which can easily be felt underfoot or detected with a guidance cane must be installed on curb ramps, entering vehicular passageways. AASHTO M 333-16 specifies this requirement in order to compensate for the lack of tactile warning cause by sloped curb ramps.
All Armor-Tile detectable warning tiles have been tested to meet or exceed the necessary ASTM testing standards, which are required for AASHTO M 333-16 compliance.