Signs 101 Manual November 2014 Office of Traffic, Safety and Technology MnDOT Signs 101 Course Manual TABLE OF CONTENTS 1. INTRODUCTION .......................................................................................................................... 1-1 1.1 Background ........................................................................................................................................ 1-1 1.2 Goals of Course .................................................................................................................................. 1-1 1.3 Disclaimer ........................................................................................................................................... 1-1 1.4 Acknowledgements ........................................................................................................................... 1-1 1.5 Contact Information ........................................................................................................................... 1-2 1.6 MnDOT OTST Website ....................................................................................................................... 1-2 1.7 Glossary of Terms ............................................................................................................................... 1-2 2. SIGNING OVERVIEW ................................................................................................................... 2-1 2.1 Purpose of Signs ................................................................................................................................. 2-1 2.2 What is Retroreflectivity? .................................................................................................................. 2-1 2.2.1 Retroreflective Sheeting Materials ............................................................................................... 2-2 2.2.2 Why is Retroreflectivity Important? ............................................................................................. 2-3 2.2.3 Minimum Retroreflectivity ........................................................................................................... 2-3 2.3 Five Principles of Traffic Control Devices ........................................................................................... 2-4 2.4 Classification of Signs ......................................................................................................................... 2-4 2.5 Design of Signs ................................................................................................................................... 2-5 2.5.1 Sign Nomenclature ....................................................................................................................... 2-5 2.5.2 Elements of Traffic Sign Design .................................................................................................... 2-6 2.5.3 Shape ............................................................................................................................................. 2-6 2.5.4 Color .............................................................................................................................................. 2-7 2.5.5 Size ................................................................................................................................................ 2-8 2.5.6 Legend .........................................................................................................................................2-11 2.6 Legal Authority for Placement of Traffic Signs ................................................................................2-12 2.6.1 Traffic Signs Installed by MnDOT Maintenance Forces ..............................................................2-12 2.6.2 Traffic Signs Installed by Contract ..............................................................................................2-12 2.6.3 Traffic Signs Installed by Others by Maintenance Permit ..........................................................2-12 2.6.4 Temporary Traffic Control Signs Installed by Construction Contracts and Public Utility Companies at Work Sites ............................................................................................................2-12 2.7 Associated Manuals .........................................................................................................................2-13 2.7.1 Federal Manual on Uniform Traffic Control Devices ..................................................................2-13 2.7.2 Minnesota Manual on Uniform Traffic Control Devices ............................................................2-14 2.7.3 Traffic Engineering Manual .........................................................................................................2-15 2.7.4 Minnesota Standard Signs Manual .............................................................................................2-16 2.7.5 Standard Signs Summary ............................................................................................................2-16 2.7.6 Guide Sign Design Manual ..........................................................................................................2-17 2.7.7 At-Grade Signing Manual ............................................................................................................2-17 2.7.8 Freeway Signing Manual .............................................................................................................2-18 3. WHY SIGNS ARE INSTALLED ........................................................................................................ 3-1 3.1 Introduction ....................................................................................................................................... 3-1 3.2 Engineering Standards ....................................................................................................................... 3-1 3.2.1 MN MUTCD Text Headings ........................................................................................................... 3-1 3.2.2 Signing Standards .......................................................................................................................... 3-2 N o v e m b e r 2 0 1 4 P a g e | i Table of Contents MnDOT Signs 101 Course Manual 3.2.3 Engineering Judgment and Documentation ................................................................................. 3-3 3.3 Signing Priorities ................................................................................................................................. 3-3 3.4 Functional Classifications of Traffic Signs .......................................................................................... 3-4 3.5 Sign Effectiveness ............................................................................................................................... 3-4 3.6 Excessive Use of Signs ......................................................................................................................3-25 3.6.1 Sign Clutter ..................................................................................................................................3-25 3.6.2 Sign Grouping ..............................................................................................................................3-25 3.7 Sign Justification ...............................................................................................................................3-25 3.7.1 Politically Motivated Signs ..........................................................................................................3-26 3.8 Advertising Signs vs. Traffic Control Signs .......................................................................................3-27 3.8.1 Logo Signs ....................................................................................................................................3-27 3.8.2 Bonus Law (1958) ........................................................................................................................3-28 3.8.3 Highway Beautification Act (1965) .............................................................................................3-29 4. TYPES OF SIGNS .......................................................................................................................... 4-1 4.1 Functional Classifications of Traffic Signs .......................................................................................... 4-1 4.1.1 Department Classification by Sign Design Type ........................................................................... 4-1 4.2 Regulatory Signs ................................................................................................................................. 4-5 4.2.1 Application of Regulatory Signs .................................................................................................... 4-5 4.2.2 Establishment of Priorities ............................................................................................................ 4-5 4.2.3 MUTCD Chapter 2B Handout ........................................................................................................ 4-5 4.3 Warning Signs ...................................................................................................................................4-23 4.3.1 MUTCD Chapter 2C Handout ......................................................................................................4-23