For lettering, a mix of uppercase and lowercase should be used where signs are intended to be read visually and not by touch. Mixing letter casing gives words a more defined shape, making them easier to identify. Type that is very fine or very thick can be difficult to read for people impacted by blindness and should be avoided.

For signs meant to be read through either touch or vision, use all uppercase characters. Uppercase is easier to read by touch. The maximum message length on such signs is three words. More information can be found in the section Tactile Signs.

For signs, use Arabic numerals and sans serif fonts, such as Tiresias Sign Font (a font specifically designed for signs), Ad Sans, Arial, Calibri, Franklin Gothic Medium, Tahoma or Verdana. The following table provides recommendations on the size of lettering (“character”) to use depending on the height of the sign and the distance from which it will be read.

Visual character heights for signage based on baseline character height and viewing distance – 2010 Americans with Disabilities Act Standards for Accessible Design.
Height to finished floor or ground from baseline of character Horizontal viewing distance Minimum character height
1,015 mm to less than or equal to 1,780 mm Less than 1,830 mm 16 mm
1,830 mm and greater 16 mm plus 3.2 mm per 305 mm of viewing distance above 1,830 mm
Greater than 1,780 mm to less than or equal to 3,050 mm Less than 4,750 mm 51 mm
4,750 mm or greater 51 mm plus 3.2 mm per 305 mm of viewing distance above 4,570 mm
Greater than 3,050 mm Less than 6,400 mm 75 mm
6,400 mm or greater 75 mm plus 3.2 mm per 305 mm of viewing distance above 6,400 mm