The 11th Edition of the Manual on Uniform Traffic Control Devices (MUTCD) includes sign size specifications for regulatory and warning signs in various sections. Section 2A.09 (Symbols) references the Standard Highway Signs and Markings publication by FHWA, which outlines five different sign sizes depending on the type of facility, including bikeways. Sections 2B.03 (Size of Regulatory Signs), 2C.03 (Size of Warning Signs and Plaques), 7B.01 (Design of School Signs), 8B.02 (Sizes of Grade Crossing Signs), and 9B.02 (Except Bicycles Regulatory Plaque) provide guidelines and requirements for the size of regulatory and warning signs, which are primarily based on speed and roadway classification. However, questions remain about whether signs should be sized based on the 85th percentile speed, the posted speed limit, or roadway classification.

The objective of this research is to develop guidelines for the appropriate sizing of regulatory and warning signs, specifically focusing on MUTCD Sections 2A.07 (Dimensions), 2B.03 (Size of Regulatory Signs), 2C.03 (Size of Warning Signs and Plaques), 7B.01 (Design of School Signs), 8B.02 (Sizes of Grade Crossing Signs), and 9B.02 (Except Bicycles Regulatory Plaque).

Research tasks and activities could include the following:

·        Conducting research on human factors to test sign visibility and comprehension at different speeds and roadway types and to evaluate whether the current MUTCD sign sizes are adequate for driver conspicuity and comprehension.

·        Examining the relationship between sign size, vehicle speed, and roadway classification.

·        Defining “high speed” and “low speed” as used throughout the MUTCD and assessing how these classifications affect appropriate sign sizing.

·        Reviewing and analyzing terminology used in MUTCD tables, such as conventional road, single lane, multiple lanes, expressway, freeway, minimum, and oversized.