This IM covers truncated domes/detectable warning systems. All truncated domes/detectable warning panels shall meet the requirements of the American with Disabilities Act (ADA), the requirements of Section 4171 of the Iowa DOT Standard Specifications and Standard Road plan MI-220.


Approved sources are listed in the Materials Approved Products Listing Enterprise (MAPLE).



Approval shall be based on the following:


1.     Submit Quality Control Procedures including testing rates, test results, material type, grade, Mill Test Reports, coating type, and installation/instruction requirements.


2.     Submit a two square foot truncated dome test sample. Samples shall represent a production lot.


Qualified suppliers/producers of truncated domes/detectable warning panels will be placed on the approved list in Appendix A of this IM. The DOT reserves the right to remove products from the approved list based upon failed field performance.





Truncated dome/detectable warning panels made with polymer shall meet the requirements of 4171.02.


Metal Panels

Truncated dome/detectable warning panels made with materials such as cast iron, steel, or stainless steel shall meet the requirements of IM 107and shall meet the requirements of 4171.04 and 4171.05.


Other Materials

Panels made with material other than polymer, polymer composite, cast iron or steel shall be evaluated on a case-by-case basis.



Acceptance of Truncated dome/detectable warning panels will be on the basis of approved source listed in IM 411 Appendix A.




The producer of the truncated domes/detectable warning systems shall furnish on each shipment day a certified bill of materials or invoice, which identifies the county, project number, contractor’s name and the number of panels. The certification of compliance shall be signed by a designated or responsible company representative and shall be stated as follows.


The materials itemized in this shipment are certified to be in compliance with American with Disabilities Act (ADA), and the Iowa Department of Transportation Standard Specifications, IMs and meet the Buy America requirements as described in IM 107 for all steel, iron products and coatings.





Authorized Signature & Date