I want the engraved sign to be seen from across the hall. How big should the sign and the letters be?
Our “rule-of-thumb” is that each inch of letter height can be seen from 50 feet away. The ANSI sign standard (see both ANSI Z535.2 and A117.1), however, is much more pessimistic. This is based on a ratio of 25 feet per inch of height for the sign message. Much depends upon the size of the building, the angle at which you approach the sign, the lighting and, even, the age and visual acuity of the viewer. An airport, parking garage or convention center needs larger letters than a sign used in a narrow hallway. Also, the headline should be larger – whereas the remaining explanatory text may be smaller. The top row leads you to the sign; once there, you can study the remaining text. In the sign market, sign legibility is increasingly a “hot button” as our population gets older. Signs read by older individuals need to be bigger and to have better lighting than those read by younger individuals. As vision deteriorates, the letters start to fill in and blur. Recently developed type fonts, how
