17-229-208 Me. Code R. § 1
The Manual on Uniform Traffic Control Devices for Streets and Highways (MUTCD) is the national standard for traffic control devices on all roads open to public travel. The MUTCD (http://mutcd.fhwa.dot.gov/) contains the standards for signing freeways and expressways for motorists who are unfamiliar with an area, but who are traveling between and through the Nation's principal traffic generating centers.
The selection of information to be presented at an interchange is critical to the safe and efficient use of the highway system. The MUTCD provides mandatory requirements for installing many freeway and expressway signs, but leaves other signing discretion to the States.One of these discretions is the selection of destinations to be used on major (interchange) guide signs and Supplemental Guide signs. Numerous facilities that warrant inclusion on supplemental guide signs, and the addition of new facilities, have posed signing problems in many states.
The MUTCD incorporates by reference the American Association of State Highway and Transportation Officials (AASHTO) Guidelines for the Selection of Supplemental Guide Signs for Traffic Generators adjacent to freeways. The guidelines contained herein were modeled on the recommendations found within the AASHTO guidance in selecting the most appropriate generators for display on freeway and expressway supplemental guide signs.
It is imperative to note that the most important guidance information for any interchange along freeways and expressways is provided on the Advance Guide Signs and Exit Direction Signs. These signs inform motorists of the route(s) and principle destination(s) accessible from an interchange. In general, that information is limited to the municipality and route name at the interchange, along with major destination points remote from, but accessible from the interchange. These signs should not be used to describe specific traffic generators unless the purpose of the interchange is primarily to provide access to that generator.
17-229 C.M.R. ch. 208, § 1