Types of signs exempt from sign permit, subject to the limitations provided: Public: Signs or objects of a noncommercial nature which are erected by, or ordered to be erected by, a public official in the performance of official duty, or by a governmental agency, such as: safety signs; traffic control signs; signs of historical interest; and names or locations of cities, towns, and villages. Temporary real estate directional: Temporary signs, not located on the premises being advertised, containing a directional arrow and advertising real estate for sale or lease, Maximum area of 1.5 square feet. Located within the County rights-of-way and within 25 feet of the corner of a street intersection. Maximum of 4 per each property advertised, with a maximum of 25 for multiple properties with an on-site common sales office. At any one intersection, there shall be only one sign facing each direction of traffic. Maximum height of 3 feet above finished grade at base of sign. Signs may only be erected between the hours of 5:00 p.m. Friday and 5:00 p.m. of the following Sunday. Signs placed or remaining within the County rights-of-way in violation of these conditions shall be considered abandoned and illegal at the time the sign is placed. Temporary institutional: Temporary signs pertaining to events sponsored by a church; library; school; hospital; fire station; community center; day care center for children; service, fraternal, or civic organizations; or other similar group. Maximum area of 12 square feet. Located within the County rights-of-way and within 25 feet of the corner of a street intersection. Maximum of 4 per sponsoring institution. Maximum height of 3 feet above finished grade at base of sign. Signs may only be erected a maximum of 15 calendar days prior to the date of the event and 1 calendar day after the conclusion of the event. Signs placed or remaining within the County rights-of-way in violation of these conditions shall be considered abandoned and illegal at the time the sign is placed.