172.516C5-HMPMC HM (Placarding) - Failure to display placard(s) so words or identification number printed on it are displayed horizontally, reading from left to right
172.516C6-HMPMC HM (Placarding) - Failure to maintain placard(s) in a condition so that the format, legibility, color, and visibility of the placard will not be substantially reduced due to damage, deterioration, or obscurement by dirt or other matter
172.516C6-HMPMC HM (Placarding) - Failure to maintain placard(s) in a condition so that the format, legibility, color, and visibility of the placard will not be substantially reduced due to damage, deterioration, or obscurement by dirt or other matter