761—118.6 (306C) Business sign blank specifications. Business signs shall meet the following specifications for the sign blank and shall not be installed until they are inspected and approved by the department.
	 118.6(1) Mainline business sign blank. Mainline business signs shall be fabricated from a rectangular sheet of aluminum, between 0.074 inches and 0.125 inches thick, with 3-inch radius corners. Gas business signs shall be 48 inches wide and 36 inches high. Food, lodging, camping and attraction business signs shall be 60 inches wide and 36 inches high.
	 118.6(2) Ramp business sign blank. Ramp business signs shall be fabricated from a rectangular sheet of aluminum, between 0.074 inches and 0.125 inches thick, with 2-inch radius corners. Gas business signs shall be 24 inches wide and 16 inches high. Food, lodging, camping and attraction business signs shall be 36 inches wide and 16 inches high.
	 118.6(3) Trailblazing business sign blank. Trailblazing business signs shall be fabricated from a rectangular sheet of aluminum, between 0.074 inches and 0.125 inches thick, with 2-inch radius corners. All trailblazing signs shall be 20 inches wide and 12 inches high.