It is unfortunate I only found the NY Post as a source for this, but it is still an interesting moment of research-to-practice. From the article:
The Capital of the World is going lower-case.
Federal copy editors are demanding the city change its 250,900 street signs — such as these for Perry Avenue in The Bronx — from the all-caps style used for more than a century to ones that capitalize only the first letters.
Changing BROADWAY to Broadway will save lives, the Federal Highway Administration contends in its updated Manual on Uniform Traffic Control Devices, citing improved readability.
Studies have shown that it is harder to read all-caps signs, and those extra milliseconds spent staring away from the road have been shown to increase the likelihood of accidents, particularly among older drivers, federal documents say.
The new regulations also require a change in font from the standard highway typeface to Clearview, which was specially developed for this purpose.
I think it is counterintuitive how much sentence-case helps with reading. For example, my mother asked me last year to help her type and print a speech she was giving. She wanted it in all caps so she could “read it more easily” while standing up. I think there is a perception of caps as larger and therefore more readable and this will have to be overcome for initiatives like this one to succeed. (I did not end up convincing my mother, even after making a nice large font, and so I printed it just how she wanted it… in all, unreadable, caps.)
Photo credit ➨ Redvers