Everything You Need to Know About Truncated Domes

Truncated Domes are one of the most recognizable adjustments we see every day that are designed to help people with disabilities. You may not know their name, but most people have noticed the bumpy yellow tiles along mass transit platforms and at crosswalks, but surprisingly few know what they are for! Let’s change that with a quick summary of all the important things you should know about truncated domes - especially if you are a business owner!


The ADA lists specific guidelines for tactile warning surfaces, also known as truncated domes. These are surfaces designed to be detectable to people who have visual impairments. The low bumps can be felt underfoot or when using a cane and will alert a visually impaired person to a potential hazard such as crossing into the street, a drop-off, or other hazards. The ADA has set guidelines regarding the height, width, and spacing of the domes so they won’t cause a trip hazard or other mobility issues.


Truncated domes should be installed where there is an elevation change or where the pedestrian will move from a pedestrian zone into potential traffic. For example, you would need to install them at a crosswalk, parking lot entrance, elevated curb, curb ramp, or transit platform.


The majority of truncated domes are yellow in color. Yellow is an excellent choice for making sure there is a visual contrast as well as a tactile one between the truncated domes and the surrounding walking surface. It is also a color that many people associate with caution as it appears on many other hazard signs and indicators.

The ADA does not specify that they must be yellow, only that they must contrast with the rest of the surface on which they are installed. However, the California state code does require that truncated domes are not just yellow but a specific shade of yellow! The color is standard shade AMS-STD 33538

If you need to install truncated domes on your property, why not book a compliance analysis with California Truncated Domes Company. We will make sure that you are both ADA and California code compliant. Call us at 415-813-9877.


Guaranteed to Meet Code & Last!

Our primary focus here at California Truncated Domes Company is handling all of your truncated dome needs. This is what we do. We are experts in this particular area of ADA construction and will make sure your truncated domes are in full compliance with ADA guidelines and the California Access Compliance Manual.

Book your $98 Compliance Analysis Today.