[Code of Federal Regulations] [Title 36, Volume 3] [Revised as of July 1, 2005] From the U.S. Government Printing Office via GPO Access [CITE: 36CFR1192.39] [Page 610] TITLE 36--PARKS, FORESTS, AND PUBLIC PROPERTY CHAPTER XI--ARCHITECTURAL AND TRANSPORTATION BARRIERS COMPLIANCE BOARD PART 1192_AMERICANS WITH DISABILITIES ACT (ADA) ACCESSIBILITY GUIDELINES FOR TRANSPORTATION VEHICLES--Table of Contents Subpart B_Buses, Vans and Systems Sec. 1192.39 Destination and route signs. (a) Where destination or route information is displayed on the exterior of a vehicle, each vehicle shall have illuminated signs on the front and boarding side of the vehicle. (b) Characters on signs required by paragraph (a) of this section shall have a width-to-height ratio between 3:5 and 1:1 and a stroke width-to-height ratio between 1:5 and 1:10, with a minimum character height (using an upper case ``X'') of 1 inch for signs on the boarding side and a minimum character height of 2 inches for front ``headsigns'', with ``wide'' spacing (generally, the space between letters shall be \1/ 16\ the height of upper case letters), and shall contrast with the background, either dark-on-light or light-on-dark. [[Page 611]]