I wonder if an amendment to the law needs to be made just on that basis - IOW, if one cannot distinguish between green and red, which are pretty contrasty to those of us who see colors "normally" it's probable that the sign would be seen as merely a blank piece of paper.
I think the law should specify 1 inch block letters (ALL OF THEM) in white on a black background, none of this white on glass (try that with macular degeneration) or 1 inch caps followed by lower case at 3/4 of an inch.
And of course, penalties for non-compliance.
![Laughing :lol:](./images/smilies/icon_lol.gif)