List of Authorized Requests for Interim Approval
Interim Approvals allow FHWA to grant authority to State and local highway agencies to use on an interim basis, "proven successful" and "proven safe" new traffic control devices or device applications that are not specifically described in the MUTCD. Such approvals are based on the results of successful experimentation, studies, or research, and an intention to place the new or revised device into a future notice of proposed amendment to the MUTCD. This process allows the traveling public and/or operating agencies to more quickly realize the safety and operational benefits associate with such devices. The following list shows the State and local highway agencies that have been granted an Interim Approval.
| Interim Approval | Number | Requestor |
|---|---|---|
| IA-1 Signal Backplate Border | IA-1.1 | North Dakota Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.2 | Kentucky Transportation Cabinet |
| IA-1 Signal Backplate Border | IA-1.3 | City of Scottsdale - Arizona |
| IA-1 Signal Backplate Border | IA-1.4 | South Carolina Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.5 | Nebraska Division of Roads |
| IA-1 Signal Backplate Border | IA-1.6 | Ohio Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.7 | City of Portland - Oregon |
| IA-1 Signal Backplate Border | IA-1.8 | Florida Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.9 | Colorado Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.10 | Illinois Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.11 | Kansas Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.12 | City of Pourey - California |
| IA-1 Signal Backplate Border | IA-1.13 | Virginia Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.14 | New York State Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.15 | California Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.16 | Washington State Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.17 | Pasco County Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.18 | Winston Salem, North Carolina |
| IA-1 Signal Backplate Border | IA-1.19 | Burlington, Iowa |
| IA-1 Signal Backplate Border | IA-1.20 | Florida Department of Transportation |
| IA-1 Signal Backplate Border | IA-1.21 | Louisiana Department of Transportation and Development |
| IA-2 Wayside Horn System | IA-2.1 | Alaska Department of Transportation |
| IA-2 Wayside Horn System | IA-2.2 | California Department of Transportation |
| IA-2 Wayside Horn System | IA-2.3 | Union Pacific Railroad Dekalb, Illinois |
| IA-4 Automated Flagger Assistance Devices | IA-4.1 | Texas Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.2 | Minnesota Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.3 | South Carolina Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.4 | Missouri Highway and Transportation Department |
| IA-4 Automated Flagger Assistance Devices | IA-4.5 | Portland, Oregon |
| IA-4 Automated Flagger Assistance Devices | IA-4.6 | Illinois Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.7 | Idaho Transportation Department |
| IA-4 Automated Flagger Assistance Devices | IA-4.8 | Maine Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.9 | Washington State Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.10 | Kansas Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.11 | Oregon Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.12 | New York State Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.13 | Vermont Agency of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.14 | Pennsylvania Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.15 | Virginia Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.16 | Florida Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.17 | North Carolina Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.18 | New Jersey Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.19 | West Virginia Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.20 | California Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.21 | Pennington County, South Dakota |
| IA-4 Automated Flagger Assistance Devices | IA-4.22 | Louisiana Department of Transportation and Development |
| IA-4 Automated Flagger Assistance Devices | IA-4.23 | Anne Arundel County DPW |
| IA-4 Automated Flagger Assistance Devices | IA-4.24 | Alabama Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.25 | Michigan Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.26 | State of New Hampshire Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.27 | Georgia Department of Transportation |
| IA-4 Automated Flagger Assistance Devices | IA-4.28 | Colorado Department of Transportation |
| IA-5 Clearview Fonts | IA-5.1 | Pennsylvania Department of Transportation |
| IA-5 Clearview Fonts | IA-5.2 | Arkansas State Highway and Transportation Department |
| IA-5 Clearview Fonts | IA-5.3 | Idaho Transportation Department |
| IA-5 Clearview Fonts | IA-5.4 | Michigan Department of Transportation |
| IA-5 Clearview Fonts | IA-5.5 | Virginia Department of Transportation |
| IA-5 Clearview Fonts | IA-5.6 | New York State Department of Transportation |
| IA-5 Clearview Fonts | IA-5.7 | Illinois Department of Transportation |
| IA-5 Clearview Fonts | IA-5.8 | Arizona Department of Transportation |
| IA-5 Clearview Fonts | IA-5.9 | Wisconsin Department of Transportation |
| IA-5 Clearview Fonts | IA-5.10 | City of Bismarck - North Dakota |
| IA-5 Clearview Fonts | IA-5.11 | I-795 South Maryland |
| IA-5 Clearview Fonts | IA-5.12 | Oklahoma Department of Transportation |
| IA-5 Clearview Fonts | IA-5.13 | Iowa Department of Transportation |
| IA-5 Clearview Fonts | IA-5.14 | Ohio Department of Transportation |
| IA-5 Clearview Fonts | IA-5.15 | City of Kennewick - Washington |
| IA-5 Clearview Fonts | IA-5.16 | Maryland State Highway Administration |
| IA-5 Clearview Fonts | IA-5.17 | West Virginia Department of Transportation |
| IA-5 Clearview Fonts | IA-5.18 | South Carolina Department of Transportation |
| IA-5 Clearview Fonts | IA-5.19 | California Department of Transportation |
| IA-5 Clearview Fonts | IA-5.20 | Kansas Department of Transportation |
| IA-5 Clearview Fonts | IA-5.21 | Alabama Department of Transportation |
| IA-5 Clearview Fonts | IA-5.22 | Vermont Agency of Transportation |
| IA-5 Clearview Fonts | IA-5.23 | Hawaii Department of Transportation |
| IA-5 Clearview Fonts | IA-5.24 | Louisiana Department of Transportation and Development |
| IA-5 Clearview Fonts | IA-5.25 | North Dakota Department of Transportation |
| IA-5 Clearview Fonts | IA-5.26 | Delaware Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.1 | Florida Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.2 | Tennessee Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.3 | Michigan Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.4 | Mississippi Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.5 | Iowa Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.6 | Idaho Transportation Department |
| IA-8 RV Friendly Symbol | IA-8.7 | Illinois Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.8 | Georgia Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.9 | Tennessee Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.10 | Alabama Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.11 | California Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.12 | Minnesota Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.13 | Arizona Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.14 | Virginia Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.15 | Montana Department of Transportation |
| IA-8 RV Friendly Symbol | IA-8.16 | Indiana Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.1 | Virginia Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.2 | Mississippi Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.3 | Virginia Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.4 | Ohio Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.5 | Iowa Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.6 | Arizona Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.7 | Texas Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.8 | Missouri Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.9 | Pennsylvania Department of Transportation |
| IA-9 More Than 6 Logo Panels | IA-9.10 | Washington State Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.1 | City of Beaverton - Oregon |
| IA-10 Flashing Yellow Arrow | IA-10.2 | City of Cheyenne, Wyoming |
| IA-10 Flashing Yellow Arrow | IA-10.3 | Wyoming Transportation Department |
| IA-10 Flashing Yellow Arrow | IA-10.4 | Yakima County, Washington |
| IA-10 Flashing Yellow Arrow | IA-10.5 | Greshan, Oregon |
| IA-10 Flashing Yellow Arrow | IA-10.6 | Coeur d'Alene, Idaho |
| IA-10 Flashing Yellow Arrow | IA-10.7 | Washington State Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.8 | Fort Smith, Arkansas |
| IA-10 Flashing Yellow Arrow | IA-10.9 | Missouri Highway and Transportation Department |
| IA-10 Flashing Yellow Arrow | IA-10.10 | Oregon Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.11 | North Carolina Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.12 | Michigan Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.13 | Colorado Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.14 | Oakland County, Michigan |
| IA-10 Flashing Yellow Arrow | IA-10.15 | City of Santee, California |
| IA-10 Flashing Yellow Arrow | IA-10.16 | Macomb County, Michigan |
| IA-10 Flashing Yellow Arrow | IA-10.17 | Wayne County, Michigan |
| IA-10 Flashing Yellow Arrow | IA-10.18 | Fayetteville, North Carolina |
| IA-10 Flashing Yellow Arrow | IA-10.19 | Utah Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.20 | El Cajon, California |
| IA-10 Flashing Yellow Arrow | IA-10.21 | Minnesota Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.22 | Pasadena, California |
| IA-10 Flashing Yellow Arrow | IA-10.23 | Garland, Texas |
| IA-10 Flashing Yellow Arrow | IA-10.24 | Lafayette, Louisiana |
| IA-10 Flashing Yellow Arrow | IA-10.25 | Alpharetta, Georgia |
| IA-10 Flashing Yellow Arrow | IA-10.26 | Fullerton, California |
| IA-10 Flashing Yellow Arrow | IA-10.27 | Victorville, California |
| IA-10 Flashing Yellow Arrow | IA-10.28 | Pontiac, Michigan |
| IA-10 Flashing Yellow Arrow | IA-10.29 | Iowa Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.30 | Idaho Transportation Department |
| IA-10 Flashing Yellow Arrow | IA-10.31 | Farmington, New Mexico |
| IA-10 Flashing Yellow Arrow | IA-10.32 | State of New Hampshire Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.33 | Tyler, Texas |
| IA-10 Flashing Yellow Arrow | IA-10.34 | Nampa, Idaho |
| IA-10 Flashing Yellow Arrow | IA-10.35 | Charlotte, North Carolina |
| IA-10 Flashing Yellow Arrow | IA-10.36 | Irving, Texas |
| IA-10 Flashing Yellow Arrow | IA-10.37 | Carson City, Nevada |
| IA-10 Flashing Yellow Arrow | IA-10.38 | Lawrence, Kansas |
| IA-10 Flashing Yellow Arrow | IA-10.39 | Pinellas County, Florida |
| IA-10 Flashing Yellow Arrow | IA-10.40 | Mooresville, North Carolina |
| IA-10 Flashing Yellow Arrow | IA-10.41 | Liberty, Missouri |
| IA-10 Flashing Yellow Arrow | IA-10.42 | Chubbock, Idaho |
| IA-10 Flashing Yellow Arrow | IA-10.43 | La Habra, California |
| IA-10 Flashing Yellow Arrow | IA-10.44 | Fort Collins, Colorado |
| IA-10 Flashing Yellow Arrow | IA-10.45 | Aurora, Colorado |
| IA-10 Flashing Yellow Arrow | IA-10.46 | Santa Clarita, California |
| IA-10 Flashing Yellow Arrow | IA-10.47 | Scottsdale, Arizona |
| IA-10 Flashing Yellow Arrow | IA-10.48 | Virginia Department of Transportation |
| IA-10 Flashing Yellow Arrow | IA-10.49 | Carrollton, Texas |
| IA-10 Flashing Yellow Arrow | IA-10.50 | Lexington/Fayette County, Kentucky |
| IA-10 Flashing Yellow Arrow | IA-10.51 | San Antonio, Texas |
| IA-10 Flashing Yellow Arrow | IA-10.52 | Boulder, Colorado |
| IA-11 Rectangular Rapid Flashing Beacon | IA-11.1 | St. Petersburg, Florida |
| IA-11 Rectangular Rapid Flashing Beacon | IA-11.2 | Las Vegas, Nevada |
| IA-11 Rectangular Rapid Flashing Beacon | IA-11.3 | North Las Vegas, Nevada |
| IA-11 Rectangular Rapid Flashing Beacon | IA-11.4 | Henderson, Nevada |
| IA-11 Rectangular Rapid Flashing Beacon | IA-11.5 | Clark County, Nevada |
