Regulations of Connecticut State Agencies
(a) The octagon shall be reserved exclusively for the STOP sign.
(b) The equilateral triangle, with one point downward, shall be reserved exclusively for the YIELD sign.
(c) The round shape shall be used for the advance warning of a railroad crossing and for the emergency evacuation route marker.
(d) The pennant shape, an isosceles triangle, with its longest axis horizontal, shall be used to warn of no passing zones.
(e) The diamond shape shall be used only to warn of existing or possible hazards either on the roadway or adjacent thereto.
(f) The rectangle, ordinarily with the longer dimension vertical, shall be used for regulatory signs, with the exception of STOP signs and YIELD signs.
(g) The rectangle, ordinarily with the longer dimensions horizontal, shall be used for guide signs, with the exception of certain route markers and recreational area guide signs.
(h) The pentagon, point up, shall be used for school advance and School Crossing signs.
(Effective November 3, 1981; Amended December 23, 2005)