Difference between revisions of "Category:902 Signals"

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[[image:902 signals.jpg|right|350px]]
 
[[image:902 signals.jpg|right|350px]]
 
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|'''[[Key Points 902 Highway Signals|Key Points]]'''
 
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Traffic signals are electrically powered traffic control devices that warn or direct vehicular and pedestrian traffic to take some specific action.  Traffic signals provide for the orderly assignment of right of way to conflicting traffic movements at intersections.
 
Traffic signals are electrically powered traffic control devices that warn or direct vehicular and pedestrian traffic to take some specific action.  Traffic signals provide for the orderly assignment of right of way to conflicting traffic movements at intersections.
  
Traffic signals are not a complete solution for traffic problems.  Traffic signals can sometime create additional congestion and cause additional delay to vehicles if improperly designed, installed, or maintained.  Correctly designed and operated traffic signals installed at [[902.2 Warrants for Traffic Signal Installation| warranted locations]] will provide for the orderly movement of traffic, increase the intersection capacity, and in some instances, tend to reduce accidents.  [[902.7 Coordination|Coordinating]] and [[902.5 Phasing and Timing the Signal|phasing and timing signals]] are very important.  
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Traffic signals are not a complete solution for traffic problems.  Traffic signals can sometime create additional congestion and cause additional delay to vehicles if improperly designed, installed, or maintained.  Correctly designed and operated traffic signals installed at [[902.3 Traffic Control Signal Needs Studies (MUTCD Chapter 4C)| warranted locations]] will provide for the orderly movement of traffic, increase the intersection capacity, and in some instances, tend to reduce accidents.  [[902.5 Traffic Control Signal Features (MUTCD Chapter 4D)#902.5.5 Coordination|Coordinating]] and [[902.5 Traffic Control Signal Features (MUTCD Chapter 4D)#902.5.36 Signal Timing|timing signals]] are very important.  
  
 
Traffic signals are listed on the Highway Right of Way and Construction Program in the description of the type of improvement if there is a probability of future signal control.  If signals cannot be justified, they are to be eliminated from the program at the earliest possible date.
 
Traffic signals are listed on the Highway Right of Way and Construction Program in the description of the type of improvement if there is a probability of future signal control.  If signals cannot be justified, they are to be eliminated from the program at the earliest possible date.
  
This article provides the [[902.1 Basis for Installation|basis for installation]] of traffic signals, discusses [[902.3 Basic Types of Signal Control| basic types of signal control]] equipment and hardware, their characteristics, uses, applications, [[902.8 Signal Operations and Maintenance|operations and maintenance]].  The policies, standards and guidelines set forth herein are in general accordance with [http://mutcd.fhwa.dot.gov/pdfs/2003r1/pdf-index.htm the ''Manual on Uniform Traffic Control Devices''] most recent edition and the subsequent rulings on requests for interpretations, changes, and experimentation, herein referred to as the MUTCD.  Clarification, elaboration, or the elimination of options of the individual items, is contained herein so that conformity of application will be promoted in Missouri.   
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|-
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|colspan="2"|'''Traffic Pamphlet'''
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|-
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|[[media:900 Traffic Signals.pdf|Traffic Signals]]
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|}
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The policies, standards and guidelines set forth herein are in general accordance with [http://mutcd.fhwa.dot.gov/index.htm the ''Manual on Uniform Traffic Control Devices''] most recent edition and the subsequent rulings on requests for interpretations, changes, and experimentation, herein referred to as the ''MUTCD''.  Clarification, elaboration, or the elimination of options of the individual items, is contained herein so that conformity of application will be promoted in Missouri.   
  
This article has a [[902.12 Glossary|glossary]] and also relates to:
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There are many aspects to be considered when inspecting construction quality and this article provides [[902.19 Construction Inspection Guidelines for Sec 902|construction inspection guidelines]] and [[902.20 Material Inspection for Sec 902|guidelines for material inspections]].
  
- [[902.4 Flashers and Signals for Schools and Other Special Applications|flashers and signals for schools and other special applications]]
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This article also has a [[902.18 Glossary|glossary]].
  
- [[902.6 Signal Indications and Signing|signal indications and signing]]
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===Nonstandard Structures===
 
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- [[902.9 Computer Applications|computer applications]]
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|-
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|'''Adaptive Traffic Signals'''
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|-
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|[http://library.modot.mo.gov/RDT/reports/Ri08026/or10020.pdf Evaluation of an Adaptive Traffic Signal System:  Route 291 in Lee's Summit]
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|-
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|'''See also:''' [http://www.modot.gov/services/OR/byDate.htm Innovation Library]
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|}
  
- [[902.10 Signal Installations and Equipment| signal installations and equipment]]
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If any lighting installation being considered will use a special or nonstandard structure or with dimensions exceeding those shown in the Standard Plans, [http://sharepoint/systemdelivery/tr/Pages/default.aspx Traffic] and [http://sharepoint/systemdelivery/br/pages/default.aspx Bridge] are to be consulted early in the project planning regarding the installation’s feasibility and necessary contract provisions.  Examples of this situation are [[901.7 Light Source and Intensity#901.7.6 High Mast Lighting|high mast lighting]] and exceeding lengths on the Standard Plans.
  
- [[902.11 Other Design Aspects of Traffic Signals|other design aspects of traffic signals]].
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Since designing details for nonstandard installations is typically performed by an outside engineer employed by the contractor or producer and is certified to MoDOT, the project contract documents must include appropriate requirements about the design standards used.  Since structures beyond MoDOT's standard designs are involved, a performance-based specification of the design signed and sealed by a Missouri Registered Professional Engineer is needed from the contractor. Certification to the current AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaries and Traffic Signals including the latest fatigue provisions is required.

Revision as of 10:36, 24 September 2018

902 signals.jpg

Traffic signals are electrically powered traffic control devices that warn or direct vehicular and pedestrian traffic to take some specific action. Traffic signals provide for the orderly assignment of right of way to conflicting traffic movements at intersections.

Traffic signals are not a complete solution for traffic problems. Traffic signals can sometime create additional congestion and cause additional delay to vehicles if improperly designed, installed, or maintained. Correctly designed and operated traffic signals installed at warranted locations will provide for the orderly movement of traffic, increase the intersection capacity, and in some instances, tend to reduce accidents. Coordinating and timing signals are very important.

Traffic signals are listed on the Highway Right of Way and Construction Program in the description of the type of improvement if there is a probability of future signal control. If signals cannot be justified, they are to be eliminated from the program at the earliest possible date.

Traffic Pamphlet
Traffic Signals

The policies, standards and guidelines set forth herein are in general accordance with the Manual on Uniform Traffic Control Devices most recent edition and the subsequent rulings on requests for interpretations, changes, and experimentation, herein referred to as the MUTCD. Clarification, elaboration, or the elimination of options of the individual items, is contained herein so that conformity of application will be promoted in Missouri.

There are many aspects to be considered when inspecting construction quality and this article provides construction inspection guidelines and guidelines for material inspections.

This article also has a glossary.

Nonstandard Structures

Adaptive Traffic Signals
Evaluation of an Adaptive Traffic Signal System: Route 291 in Lee's Summit
See also: Innovation Library

If any lighting installation being considered will use a special or nonstandard structure or with dimensions exceeding those shown in the Standard Plans, Traffic and Bridge are to be consulted early in the project planning regarding the installation’s feasibility and necessary contract provisions. Examples of this situation are high mast lighting and exceeding lengths on the Standard Plans.

Since designing details for nonstandard installations is typically performed by an outside engineer employed by the contractor or producer and is certified to MoDOT, the project contract documents must include appropriate requirements about the design standards used. Since structures beyond MoDOT's standard designs are involved, a performance-based specification of the design signed and sealed by a Missouri Registered Professional Engineer is needed from the contractor. Certification to the current AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaries and Traffic Signals including the latest fatigue provisions is required.