Clearview font

Reading about fonts mandated by the federal government for use on highway road signs, I learned two terms : halation and overglow:

On a road with a posted speed limit of 45 mph, a driver is traveling at 66 feet per second. With Clearview-Bold, the desired destination legend is recognized 1.3 seconds earlier (84 feet) and with greater accuracy, giving the driver significantly more time to react to the information displayed.

Standard Alphabets for Traffic Control Devices