Some cities and states mount their traffic signals horizontally. And I’ve always wondered why. And evidently, so do you. This is one of the most-asked questions you and other road fans have sent me.
So, I dug in and found an answer: Four design considerations engineers in Texas, Florida, Nebraska, and New Mexico think about which leads to horizontal traffic signals.
- Email correspondence with Denise M. of the Nebraska Department of Transportation, 3 Feb. 2022.
- Email correspondence with Alecia C. of the Florida Department of Transportation, 22 Dec. 2021.
- “Figure 4D-4. Lateral and Longitudinal Location of Primary Signal Faces,” Manual on Uniform Traffic Control Devices, p.465. Federal Highway Administration, 2009. https://mutcd.fhwa.dot.gov/pdfs/2009/mutcd2009edition.pdf
- “Traffic Signal Supports, Indications, and Signing,” Buckholz, Jeffrey.
- Continuing Education and Development, C03-024. Accessed via Google on 1 Mar 2023. https://www.cedengineering.com/userfiles/Traffic%20Signal%20Supports%20-R1.pdf
- “Traffic signal head details,” Texas Department of Transportation, 2018. https://ftp.dot.state.tx.us/pub/txdot-info/dal/specinfo/trfstds/traffic-signal-head.pdf
- “Traffic signs and signals,” Texas Department of Transportation. https://www.txdot.gov/safety/traffic-signs-signals.html
- “DMS – 11120 Vehicle signal heads,” Texas Department of Transportation, 2008. https://ftp.dot.state.tx.us/pub/txdot-info/cst/DMS/11000_series/pdfs/11120.pdf
- “Item 682, Vehicle and Pedestrian Signal Heads,” Texas Department of Transportation. https://ftp.dot.state.tx.us/pub/txdot-info/cmd/cserve/specs/2014/standard/s682.pdf
- “The 8 and 9 July 1993 Nebraska Derecho: An Observational Study and Comparison to the Climatology of Related Mesoscale Connective Systems,” Bently, M., 1997. https://journals.ametsoc.org/view/journals/wefo/12/3/1520-0434_1997_012_0678_tajnda_2_0_co_2.xml
- “Hurricane Ian ranks among strongest wind recorded in Florida,” WMUR, 28 Sep 2022. https://www.wmur.com/article/hurricane-ian-strongest-wind-florida-92822/41433810
- “Local 10 reflects on Hurricane Andrew coverage, 25 years later,” WPLG, 19 Mar. 2019. https://www.local10.com/video/news/2019/03/19/local-10-reflects-on-hurricane-andrew-coverage-25-years-later/
- “1992 WWL (870 AM) Hurricane Andrew,” Tyree, David and Franklin, F. Michael. WWL Newsradio 870, 1992. Archived via Blaine Stewart. https://www.youtube.com/watch?v=-BUVsuBipvs