Oregon Revised Statutes Highways, Roads, Bridges and Ferries § 377.805

(1) The Travel Information Council shall by regulation prescribe the size, shape, color, lighting, and lettering of and manner of displaying messages on tourist oriented directional signs, logo signs and motorist informational signs.

(2) When appropriate, logo signs, tourist oriented directional signs and motorist informational signs shall be displayed in tiers or on panels. With the approval of the Director of Transportation, the council shall specify the types of locations where such a sign or panel may be erected or maintained, and the size, shape, lighting and other characteristics of the panels, including the location of signs thereon. Tiers or panels may be established at reasonably spaced intervals or at sign plazas.

(3) Distinctive signs shall be allowed to the extent considered practicable by the council. Logo signs shall be the primary means used to indicate the availability of one or more brands of motor fuel. Logos shall be of the shape, color and wording customarily used by the company. Logo signs and tourist oriented directional signs shall be placed adjacent to the traveled portion of the highway so as to be easily read by motorists without slowing or stopping.