 Specifications for current enforceable ADA detectable warnings truncated domes regulation for the general public, is the United States Department of Justice 28 CFR part 36 Revised as of July 1, 1994.Excerpt from ADA 4.3 Accessible Routes, 4.3.6 Surface Textures, 4.5 Ground Floor Surfaces, 4.5.3 - Carpet, 4.5.4 - Gratings - Textures.Tactile ground surface indicators are installed broadly in major cities such as Beijing, Shanghai, Dalian and Guangzhou.