18. The signs referred to in section 17 and every other sign erected by a club must be the following colours and bear the following markings and numerals:(1) regulatory signs must have a black border 6 mm in width set in 4 mm from the edge of the sign and bear a black symbol or black letters on a white background, except for the mandatory stop sign, which must bear white letters 127 mm in height and have a white border 12 mm in width on a red background;
(2) warning signs, with the exception of hazard markers, must have a black border 6 mm in width set in 4 mm from the edge of the sign and bear a black symbol on a yellow background, except for the D-10-1 sign, which is red; and
(3) roadwork signs must have a black border 6 mm in width set in 4 mm from the edge of the sign and bear a black symbol on an orange background.