The following words and phrases when used in this act shall have the meanings given to them in this section unless the context clearly indicates otherwise:

“Department.” The Department of Transportation.

“Obstruction of view.” When the intent of the advertising is not discernible for a total of five seconds in the viewing zone.

“Off-premises outdoor advertising device.” An outdoor advertising device as defined by, and for which a permit has been issued pursuant to, the act of December 15, 1971 (P.L.596, No. 160), known as the Outdoor Advertising Control Act of 1971,¹ or for which a permit has been issued pursuant to any local ordinance and which advertises activities not conducted on the property on which it is located.

“On-premises outdoor advertising device.” An outdoor advertising device which advertises activities conducted on the property on which it is located.

“Outdoor advertising device” or “device.” Both on-premises outdoor advertising devices and off-premises outdoor advertising devices.

“Screening” or “screened.” The obstruction of view of a device as viewed from the center of the lane of traffic of the highway and from a height of no more than 60 inches above the highway surface.

“Vegetation.” All woody and herbaceous plants growing within the legal right-of-way as described in section 410 of the act of June 1, 1945 (P.L.1242, No. 428), known as the State Highway Law.²

“Viewing zone.” That distance measured along the center of the lane of traffic of a highway which a vehicle will travel at the posted speed limit.