Signing Standards
All signing for county roads on the state highway system use
D-21 series signs for named county roads or D-20 signs for numbered
roads. Both series use white legend on green background. The abbreviation
for “county road” used on signs with road numbers is “CO RD.”
The recommended minimum letter size is six inches, except
where circumstances restrict the overall size of the sign. Advance
guide signs should be placed at least 200 feet in advance of the intersection.
On major highways or for major county roads, larger letter size
and increased advance distance from the county road should be considered.
See (SHSD) for sign
details for county road signs. See the
for sheeting, font, and substrate
requirements for county road signs.