The FHWA says that a '125 mm (5 in)' font can be seen at up to '50 m (175 ft)'.
See table 2C-4 'Guidelines for the advance placement of warning signs'. http://mutcd.fhwa.dot.gov/pdfs/millennium/06.14.01/2cndi.pdf Incidentally, they miss a trick by keeping imperial units in this document. I don't mean the face of the signs, I just mean things like sign size and placement. I thought that the Federal government could use metric only for such regulations to be used by engineers. -- Terry Simpson Human Factors Consultant [EMAIL PROTECTED] www.connected-systems.com Phone: +44 7850 511794
