Nothing in this chapter shall prohibit the erection of any sign required by state or federal law. Examples of such signs include, but are not limited to, signs indicating whether smoking is permitted within a building and signs warning of the presence of certain designated substances. Signs issued by a governmental agency for the purpose of aiding compliance with state or federal law shall not require architectural review pursuant to this code. (Ord. 96-O-2257, eff. 5-10-1996)