Sign Lettering Letter size is a function of the viewing distance and the amount of time available for viewing.
Use the following minimum letter sizes for signs that will be viewed from a moving vehicle.
Maintenance Level 2, 3, 4, and 5 roads
•20 mph or less
3” letters
•21-34 mph
4” letters
•35-50 mph
5” letters
•More than 50 mph
6” letters
Motorized Trails
•25 mph or less
2” letters
•More than 25 mph
3” letters
Use the following minimum letter sizes for signs that will be viewed from a stationary position. The size of lettering depends on the distance from which the message will be viewed.
Non-Motorized Trails
•Most situations
1” letters
Interpretive Informational Signs
•Viewed from 4 feet or less
5/8” letters
•Viewed from 5-7 feet
3/4” letters
•Viewed from 8-12 feet
1” letters
•Viewed from 13-20 feet
2” letters
•Viewed from over 20 feet
3” letters
Fonts
•1”-5” letters
Gothic C font
•5”-6” letters
Gothic D font
•7” and above letters
Gothic E font
Symbol Size Symbol size is a function of viewing distance and time available for viewing.
Roads
