When is it acceptable to post more than one sign on a single post?
Unless the signs are related to each other, all signs should be posted separately and at least 200 feet apart. See QA for longitudinal spacing of signs. Note that plaques (designated with a P in the sign designation) are always posted with the sign they supplement and are never posted alone.
Here are some examples from MUTCD Section 2A.16 Standardization of Location.
- One sign supplements another;
- Route or directional signs are grouped to clarify information to motorists;
- Regulatory signs that do not conflict with each other are grouped, such as turn prohibition signs posted with one
way signs or a parking regulation sign
posted with a speed limit sign; or
- Street name signs are posted with a
stop or yield sign.
Figure from MUTCD Section 2A.16.
MUTCD Section 2A.16 Standardization of Location