Outdoor advertising signs are not prohibited, but there are specific limitations such as where they may be located, how close they can be to other permitted signs, how large they can be, and how they must be maintained.

• Signs may be placed in areas that are zoned for commercial and industrial use or in unzoned areas where commercial or industrial activities are located. It's the departments responsibility to determine if those areas qualify for the placement of signs.
• Permitted signs must be at least 500 feet apart along interstate highways and access controlled highways Signs must be 300 feet apart along primary highways that are not designated as access controlled. Outside of incorporated cities and towns they cannot be closer than 500 feet from a public park or public forest boundary. Also, they must be at least 500 feet from highway rest areas or from an interstate highway interchange
• Signs may vary in size but cannot be larger than 672 square feet in area. (A sign that is 48 feet long and 14 feet high is 672 square feet.) The sign cannot be more than 48 feet long and no higher than 30 feet above the surface of the roadway.
• In addition, there are several other regulations that may apply. Before applying for a sign permit, you should discuss your plans with an OAC Contact.