The National Academies Press

Currently Skimming:

Pages 109-186

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.

From page 109... ... COUNTERMEASURES 109 Appendix: Countermeasure Glossary This Countermeasure Glossary provides supplemental information on each of the countermeasures recommended in this Guide. Each countermeasure located in this appendix provides key information for practitioners to consider when assessing, choosing, refining, and finalizing countermeasures to address specific crash types or safety performance objectives. Read the entire page →
From page 110... ... COUNTERMEASURESAPPENDIX: COUNTERMEASURE GLOSSARY 110 Table of Countermeasures Countermeasure Applicable to Appendix Page NumberSignalized Intersection Unsignalized Intersection Active Warning Beacons 117 Advance Stop/Yield Lines 119 All-Walk Phase 121 Bicycle Lane Extension Through Intersections 123 Bicycle Signals 125 Bike Boxes 127 Continuous Raised Medians or Hardened Centerlines 129 Crossing Barriers 131 Crossing Islands 133 Curb Extensions 135 Curb Radius Reduction 137 Gateway Treatments (R1-6 Signs) 139 Grade-Separated Crossings 141 High-Visibility Crosswalk Markings 143 In-Street Pedestrian Crossing Signs 145 Leading Bicycle Interval 147 Leading Pedestrian Interval 149 Lighting 151 Mini-Traffic Circles 153 Mixing Zone Treatments 155 No Turn on Red Signs 157 Parking Restrictions at Crossing Locations/Daylighting 159 Passive Bicycle Signal Detection 161 Pedestrian Countdown Signals 163 Pedestrian Hybrid Beacon 165 Protected Intersections 167 Protected Phases 169 Raised Crossings 171 Rectangular Rapid Flash Beacon 173 Road Diet/Rechannelization 175 Roundabout 177 Signal Timing 179 Traffic Signals 181 Two-Stage Bicycle Turn Queue Boxes 183 Read the entire page →
From page 111... ... 111 COUNTERMEASURES Countermeasure Summary Matrix (Table 25) This is a copy of the Countermeasure Summary Matrix included as Table 25 in Chapter 4. Read the entire page →
From page 112... ... 112 COUNTERMEASURESCOUNTERMEASURE SUMMARY MATRIX (TABLE 25) Countermeasure Effectiveness Public Process Motorist Traveling Straight Motorist Turning Tier 1: Supports motorist yielding Tier 2: Requires intervention to induce motorist yielding Tier 3: Separate modes or require motorists to stop 1 to 5 scale: 1 = no public process and 5 = extensive public process M ot or is t f ai le d to y ie ld to pe de st ria n Pe de st ria n fa ile d to y ie ld Pe de st ria n da sh Bi ke c ro ss in g pa th s wi th un co nt ro lle d m ot or is t Bi ke ri de s th ro ug h/ ou t – ST OP s ig n M ot or is t d riv es o ut in to bi ke – S TO P co nt ro lle d Bi ke ri de s th ro ug h/ ou t – si gn al iz ed in te rs ec tio n M ot or is t l ef t t ur ni ng in to pe de st ria n pa ra lle l p at h M ot or is t r ig ht tu rn in g in to pe de st ria n pa ra lle l p at h M ot or is t r ig ht tu rn in g in to bi ke – s am e di re ct io n M ot or is t l ef t t ur ni ng in to bi ke – o pp os ite d ire ct io n Crossing Islands H H H 3 Curb Extensions M M M 1 Curb Radius Reduction M M M 1 Gateway Treatments (R1-6 Signs) Read the entire page →
From page 113... ... 113 COUNTERMEASURES Countermeasure Effectiveness Public Process Motorist Traveling Straight Motorist Turning Tier 1: Supports motorist yielding Tier 2: Requires intervention to induce motorist yielding Tier 3: Separate modes or require motorists to stop 1 to 5 scale: 1 = no public process and 5 = extensive public process M ot or is t f ai le d to y ie ld to pe de st ria n Pe de st ria n fa ile d to y ie ld Pe de st ria n da sh Bi ke c ro ss in g pa th s wi th un co nt ro lle d m ot or is t Bi ke ri de s th ro ug h/ ou t – ST OP s ig n M ot or is t d riv es o ut in to bi ke – S TO P co nt ro lle d Bi ke ri de s th ro ug h/ ou t – si gn al iz ed in te rs ec tio n M ot or is t l ef t t ur ni ng in to pe de st ria n pa ra lle l p at h M ot or is t r ig ht tu rn in g in to pe de st ria n pa ra lle l p at h M ot or is t r ig ht tu rn in g in to bi ke – s am e di re ct io n M ot or is t l ef t t ur ni ng in to bi ke – o pp os ite d ire ct io n Parking Restrictions at Crossing Locations/ Daylighting H H H 2 Passive Bicycle Signal Detection H H H 1 Pedestrian Countdown Signals H H H 1 Pedestrian Hybrid Beacon M H H 1 Protected Intersections H H H 3 Protected Phases M H H 4 Raised Crossings M H H 3 Rectangular Rapid Flash Beacon H M L 1 Road Diet/Rechannelization H H H 5 Roundabout H H H 5 Signal Timing H H H 3 Traffic Signals M M M 3 Two-Stage Bicycle Turn Queue Boxes M M M 1 Note: H = High, M = Medium, L = Low Read the entire page →
From page 114... ... 114 COUNTERMEASURESDESIGN TRADE-OFFS OF SAFETY COUNTERMEASURES (TABLE 29) Design Trade-Offs of Safety Countermeasures (Table 29) Read the entire page →
From page 115... ... 115 COUNTERMEASURES Spatial Impact Estimated Cost Maintenance Cost Public Process Motorists Pedestrians Bicyclists Operations User Comfort Safety Operations User Comfort Safety Operations User Comfort Safety High-Visibility Crosswalk Markings Small $ $ 1 + / − + + / − + + + + + + In-Street Pedestrian Crossing Signs Small $ $ 1 + / − − + / − + + + + + + Leading Bicycle Interval Small $$ $$ 1 − + + / − + + + + + + Leading Pedestrian Interval Small $ $ 1 − + + / − + ++ + + ++ + Lighting Small $$ $$ 4 + + ++ + + ++ + + ++ Mini-Traffic Circles Large $$ $$ 4 − − + − − + − − + / − Mixing Zone Treatments Moderate $$ $$ 3 + + / − + / − + / − + / − + / − + / − − + No Turn on Red Signs Small $ $ 1 − − + / − ++ ++ ++ ++ ++ ++ ++ Parking Restrictions at Crossing Locations/ Daylighting Moderate $ $ 2 + / − + ++ + + ++ + + ++ Passive Bicycle Signal Detection Small $$ $$ 1 + / − + / − + / − + / − + / − + / − ++ ++ + Pedestrian Countdown Signals Small $$ $$ 1 + / − + / − + / − + ++ ++ + ++ ++ Pedestrian Hybrid Beacon Small $$$ $$$ 4 − + + + ++ ++ + ++ ++ Protected Intersections Large $$$$ $$$$ 3 − ++ + + ++ ++ ++ ++ ++ Protected Phases Small $ $ 4 − − ++ + − − ++ ++ − − ++ ++ Raised Crossings Moderate $$ $$ 3 − − + ++ ++ ++ ++ ++ ++ Read the entire page →
From page 116... ... 116 COUNTERMEASURESDESIGN TRADE-OFFS OF SAFETY COUNTERMEASURES (TABLE 29) Spatial Impact Estimated Cost Maintenance Cost Public Process Motorists Pedestrians Bicyclists Operations User Comfort Safety Operations User Comfort Safety Operations User Comfort Safety Rectangular Rapid Flash Beacon Small $$ $$ 1 + / − + / − + / − + / − + + + + + Road Diet/ Rechannelization Large $$ $$ 5 − + / − ++ ++ ++ ++ ++ ++ ++ Roundabout Large $$$$ $$$$ 5 + + + + + + − + / − + − + / − Signal Timing Small $ $ 3 + / − + / − + + + + + + + Traffic Signals Small $$$$ $$$$ 3 + / − + + / − + / − + + / − + / − + + / − Two-Stage Bicycle Turn Queue Boxes Small $ $ 1 + / − + + / − + / − + + / − + / − + + / − KEY ++ very positive benefit + positive benefit + / − neutral − disbenefit − − strong disbenefit Relative Cost $ = <2,500 $$ = 2,500–49,999 $$$ = 50,000–150,000 $$$$ = >150,000 Public Process 1. Read the entire page →
From page 117... ... COUNTERMEASURES 117 Active warning beacons are user-actuated flashing lights that supplement warning signs at unsignalized crossings (NACTO 2012) , including path and road crossings. Read the entire page →
From page 118... ... COUNTERMEASURES 118 ACTIVE WARNING BEACONS Complementary Countermeasures Should be installed with the following treatments: • High-visibility crosswalk markings. • Curb ramps. Read the entire page →
From page 119... ... COUNTERMEASURES 119 Advance stop/yield lines are pavement markings placed 20 to 50 feet in advance of an uncontrolled and unsignalized pedestrian or bicycle crossing. This treatment increases the distance between where drivers have stopped or yielded and the crosswalk or bicycle crossing, which improves the visibility of crossing pedestrians and bicyclists to motorists and helps to reduce multiplethreat crashes. Read the entire page →
From page 120... ... COUNTERMEASURES 120 ADVANCE STOP/YIELD LINES Complementary Countermeasures Should be installed with the following treatments: • High-visibility crosswalk markings. • Stop Here for Pedestrians or Yield Here to Pedestrians signs (MUTCD R1-5 series) Read the entire page →
From page 121... ... COUNTERMEASURES 121 Applicable Crash Types Applicable Contexts • Densely populated urban areas, often in downtown areas. • Signalized intersections with high instances of turning-vehicle–pedestrian conflicts. Read the entire page →
From page 122... ... COUNTERMEASURESALL-WALK PHASE 122 Considerations • Typically requires longer overall signal cycle lengths which increases delay for all users. • Nonvisual guidance should be provided for pedestrians who are visually impaired so that they know when it is an appropriate time to cross; normal auditory cues are not applicable at locations with exclusive pedestrian phases. Read the entire page →
From page 123... ... COUNTERMEASURES 123 Applicable Crash Types Applicable Contexts • Locations with bicycle lanes or separated bike lanes where it is desired to delineate the bicycle crossing. • Locations where right- or left-turning vehicles cross through moving bicyclists, especially at intersections along major bike routes. Read the entire page →
From page 124... ... COUNTERMEASURESBICYCLE LANE EXTENSION THROUGH INTERSECTIONS 124 Complementary Countermeasures Should be installed with the following treatments: • Bicycle lanes. • Separated bike lanes. Read the entire page →
From page 125... ... COUNTERMEASURES 125 Applicable Crash Types Applicable Contexts • Signalized intersections with high bicycle volumes and high turning-vehicle volumes. • Locations where a highly used bicycle route (including shared-use path) Read the entire page →
From page 126... ... COUNTERMEASURESBICYCLE SIGNALS 126 Complementary Countermeasures Should be installed with the following treatments: • Bicycle signal sign (MUTCD R10-10; R10-22 if using passive detection; R10-24 or R10-26 if using active detection) Read the entire page →
From page 127... ... COUNTERMEASURES 127 Applicable Crash Types Applicable Contexts • Signalized intersections with medium to high volumes of bicyclists and motor vehicles. • Intersections where large vehicles are common. Read the entire page →
From page 128... ... COUNTERMEASURESBIKE BOXES 128 Complementary Countermeasures Should be installed with the following treatments: • Bicycle lane up to 50 feet in advance of the bike box. • Stop Here on Red sign (MUTCD R10-6 series) Read the entire page →
From page 129... ... COUNTERMEASURES 129 Applicable Crash Types Applicable Contexts • Intersection or midblock crossing locations. • Locations where it is desired to restrict left-turning motorists to improve safety, such as those where left-turning motorists do not sufficiently yield, turn too fast, or cut across centerlines. Read the entire page →
From page 130... ... COUNTERMEASURESCONTINUOUS RAISED MEDIANS OR HARDENED CENTERLINES 130 Considerations • Crossing islands greater than 6 or 8 feet in width and wider crossings should be considered where pedestrian or bicycle volumes are higher. • Landscaping should not obstruct visibility between pedestrians and approaching motorists. Read the entire page →
From page 131... ... COUNTERMEASURES 131 At some locations, crossing a street or roadway would expose bicyclists and pedestrians to an elevated risk of being struck by a motor vehicle if they attempt to cross at locations which are not designed to provide safe crossings. While it is generally preferred to create safe crossings, in situations where that is not practical or feasible, it may be necessary to consider the installation of continuous barrier or fencing to channelize pedestrians to a safer crossing as signs are not typically effective. Read the entire page →
From page 132... ... COUNTERMEASURESCROSSING BARRIERS 132 Considerations • When installing a crossing barrier, provide pedestrian wayfinding to alternative crossing location(s) Read the entire page →
From page 133... ... COUNTERMEASURES 133 Crossing islands are roadway treatments designed to provide refuge for pedestrians and bicyclists between motor vehicle travel lanes at intersections and midblock locations. To provide pedestrian refuge, they must be a minimum width of 6 feet to meet pedestrian accessibility requirements. Read the entire page →
From page 134... ... COUNTERMEASURESCROSSING ISLANDS 134 • Curb ramps (if no other accommodation provided) Read the entire page →
From page 135... ... COUNTERMEASURES 135 Curb extensions (also known as "bulb-outs," or "neck downs") decrease the width of a roadway through the physical extension of a curb line or sidewalk. Read the entire page →
From page 136... ... COUNTERMEASURESCURB EXTENSIONS 136 • Parking restrictions/daylighting. • Lighting. Read the entire page →
From page 137... ... COUNTERMEASURES 137 Curb radius reductions are a strategy to reduce turning speeds for vehicles by forcing sharper turns; they also create larger waiting areas for crossing pedestrians. All curb radius geometries should be designed to prevent turning vehicles from tracking over the curb which could injure people waiting on the corner. Read the entire page →
From page 138... ... COUNTERMEASURESCURB RADIUS REDUCTION 138 Considerations • A curb radius should be chosen to accommodate the most frequent large design vehicle at the intersection, not the occasional large vehicle size. • Parking or bicycle lanes at an intersection can increase the effective radius. Read the entire page →
From page 139... ... COUNTERMEASURES 139 Gateway treatments are created by the placement of Stop or Yield to Pedestrian signs (MUTCD R1-6 or R1-6a) on the left and right side of all travel lanes to create a "gateway configuration" at an uncontrolled crosswalk. Read the entire page →
From page 140... ... COUNTERMEASURESGATEWAY TREATMENTS (R1-6 SIGNS) 140 May be installed with the following treatments: • Curb extensions. Read the entire page →
From page 141... ... COUNTERMEASURES 141 Sometimes it is necessary to completely separate pedestrians and/or bicyclists from vehicular traffic. Grade-separated crossings (also known as overpasses and underpasses) Read the entire page →
From page 142... ... COUNTERMEASURESGRADE-SEPARATED CROSSINGS 142 Considerations • Overpasses and underpasses must accommodate all persons, as required by the American Disabilities Act. • Entrances and exits to overpasses and underpasses should be clearly visible to encourage pedestrian/bicyclist use. Read the entire page →
From page 143... ... COUNTERMEASURES 143 Applicable Crash Types Applicable Contexts • All controlled intersections. • Uncontrolled locations that meet the requirements listed in MUTCD Section 3B.18 (2012) Read the entire page →
From page 144... ... COUNTERMEASURESHIGH-VISIBILITY CROSSWALK MARKINGS 144 Considerations • Crossings with motor vehicle speeds above 30 mph, more than one lane in one direction, or an AADT above 9,000 should supplement high-visibility crosswalk markings with additional treatments (Zegeer et al. Read the entire page →
From page 145... ... COUNTERMEASURES 145 This treatment involves placing Stop or Yield to Pedestrian signs (MUTCD R1-6 or R1-6a) in the roadway at the centerline of an uncontrolled crosswalk. Read the entire page →
From page 146... ... COUNTERMEASURESIN-STREET PEDESTRIAN CROSSING SIGNS 146 Considerations • The signs should be placed on a center line, on a lane line, or on a median island at the crosswalk. • Signs can be placed up to 50 feet away (Van Houten and Hochmuth 2017) Read the entire page →
From page 147... ... COUNTERMEASURES 147 Leading bicycle intervals (LBIs) provide bicyclists a head start when crossing at a signalized intersection. Read the entire page →
From page 148... ... COUNTERMEASURESLEADING BICYCLE INTERVAL 148 Complementary Countermeasures Should be installed with the following treatments: • Bicycle Signal sign (MUTCD R10-10) if bicycle signal is present, otherwise, direct bicyclists to follow pedestrian signal (MUTCD R9-5) Read the entire page →
From page 149... ... COUNTERMEASURES 149 Leading pedestrian intervals (LPIs) provide pedestrians a head start when crossing at a signalized intersection. Read the entire page →
From page 150... ... COUNTERMEASURESLEADING PEDESTRIAN INTERVAL 150 Complementary Countermeasures Should be installed with the following treatments: • High-visibility crosswalk markings. • Lighting. Read the entire page →
From page 151... ... COUNTERMEASURES 151 Illumination at crosswalks and along the roadway can help increase visibility for pedestrians and bicyclists, particularly at approaches to crossings. Studies show that increasing or adding lighting to crosswalks, road segments, and intersections improves pedestrian and bicyclist safety by reducing crashes, increasing yielding and compliance with traffic control devices, and improving visibility. Read the entire page →
From page 152... ... COUNTERMEASURESLIGHTING 152 Considerations • Install lighting on both sides of arterial streets and streets in commercial districts. • Use uniform lighting levels. Read the entire page →
From page 153... ... COUNTERMEASURES 153 Mini-traffic circles are a traffic-calming device that can take the place of, or supplement, an all-way stop-controlled intersection. They may also be installed at intersections with no control or with all-way or 2-way stop or yield control. Read the entire page →
From page 154... ... COUNTERMEASURESMINI-TRAFFIC CIRCLES 154 Considerations • Do not make generous allowances for motor vehicles by increasing the turning radii -- this compromises pedestrian and bicyclist safety. • Larger vehicles that need access to streets (e.g., school buses and fire engines) Read the entire page →
From page 155... ... COUNTERMEASURES 155 Mixing zones are locations within intersections where bicyclists approach an intersection in a bicycle lane or separated bicycle lane that terminates in a shared motor vehicle turn lane. The shared lane requires turning motorists to enter or cross the bicyclist's travel path, mixing bicycles with motor vehicles. Read the entire page →
From page 156... ... COUNTERMEASURESMIXING ZONE TREATMENTS 156 Complementary Countermeasures Should be installed with the following treatments: • Bike lanes. • Separated bike lanes. Read the entire page →
From page 157... ... COUNTERMEASURES 157 In most communities, turning right on red is a default condition of existing laws. To restrict it, a sign most be posted at the signalized intersection for each approach where the restriction is desired. Read the entire page →
From page 158... ... COUNTERMEASURESNO TURN ON RED SIGNS 158 Complementary Countermeasures Should be installed if one or more of the following treatments are used: • Leading pedestrian interval. • Leading bicycle interval. Read the entire page →
From page 159... ... COUNTERMEASURES 159 When vehicles are parked too close to pedestrian and bicycle crossings, they can limit the sightlines between oncoming motorists and pedestrians or bicyclists needing to cross the street which can increase crash risk. Removing parking space(s) Read the entire page →
From page 160... ... COUNTERMEASURESPARKING RESTRICTIONS AT CROSSING LOCATIONS/DAYLIGHTING 160 Complementary Countermeasures Should be installed with the following treatments: • No Parking sign (MUTCD R7 series) Read the entire page →
From page 161... ... COUNTERMEASURES 161 At signalized intersections that require users to be detected to actuate a signal, detection should be designed to accommodate bicyclists. Properly designed detection can deter unsafe behaviors, such as disregarding red signal indications, by reducing delay at signalized intersections. Read the entire page →
From page 162... ... COUNTERMEASURESPASSIVE BICYCLE SIGNAL DETECTION 162 Complementary Countermeasures Should be installed with the following treatments: • Bicycle signal sign (MUTCD R10-10) if bicycle signal is being used. Read the entire page →
From page 163... ... COUNTERMEASURES 163 Pedestrian signals and countdown signals provide positive guidance to pedestrians regarding the permitted signal interval to cross a street and prohibit pedestrian crossings when conflicting traffic may impact pedestrian safety. Ideally, every signalized intersection should have a pedestrian signal head. Read the entire page →
From page 164... ... COUNTERMEASURESPEDESTRIAN COUNTDOWN SIGNALS 164 Considerations • Pedestrian signals should be clearly visible to pedestrians at all times when in the crosswalk or waiting on the far side of the street. • Quick response to the button or feedback to the pedestrian registering the signal's actuation should be programmed into the system; excessive delay encourages noncompliance. Read the entire page →
From page 165... ... COUNTERMEASURES 165 Pedestrian Hybrid Beacons (PHBs) , also called HAWKs, are signals installed at unsignalized major street crossing locations to help pedestrians cross the street safely. Read the entire page →
From page 166... ... COUNTERMEASURESPEDESTRIAN HYBRID BEACON 166 Complementary Countermeasures Should be installed with the following treatments: • High-visibility crosswalk markings. • Crosswalk Stop on Red sign (MUTCD R10-23) Read the entire page →
From page 167... ... COUNTERMEASURES 167 Protected intersections maintain a physical separation between motorists and bicyclists up to the intersection. They are designed to slow turning motorist speeds to induce yielding and to improve the sight line between motorists and bicyclists to reduce conflicts between turning motorists and through moving bicyclists. Read the entire page →
From page 168... ... COUNTERMEASURESPROTECTED INTERSECTIONS 168 Complementary Countermeasures Should be installed with the following treatments: • Bike lanes. • Separated bike lanes. Read the entire page →
From page 169... ... COUNTERMEASURES 169 Protected phases at intersections provide a way to separate vehicular traffic from pedestrian and/or bicyclist movements, particularly for left-turns when concurrent phasing would result in a conflict with crossing pedestrians and left-turning vehicles and right-turns when concurrent phasing would result in a conflict with through bicyclists and right-turning vehicles. CMF/Rating 0.64 for exclusive pedestrian phase for vehicle–pedestrian crashes (ITE 2004) Read the entire page →
From page 170... ... COUNTERMEASURESPROTECTED PHASES 170 Considerations • Signal timing decisions should consider the needs of pedestrians, bicyclists, trucks, buses, and other motor vehicles. • Signal timing decisions should consider the volume of right- and left-turning motorists. Read the entire page →
From page 171... ... COUNTERMEASURES 171 CMF/Rating 0.54 for fatal/injury crashes (Bahar et al. Read the entire page →
From page 172... ... COUNTERMEASURESRAISED CROSSINGS 172 Complementary Countermeasures Should be installed with the following treatments: • High-visibility crosswalk markings. • Curb ramps. Read the entire page →
From page 173... ... COUNTERMEASURES 173 Applicable Crash Types Applicable Contexts • Roadways with low-to-medium vehicle volumes. • Roadways with posted speeds less than 40 mph. Read the entire page →
From page 174... ... COUNTERMEASURESRECTANGULAR RAPID FLASH BEACON 174 Complementary Countermeasures Should be installed with the following treatments: • High-visibility crosswalk markings. • Advance stop/yield lines on multilane approaches. Read the entire page →
From page 175... ... COUNTERMEASURES 175 The number of lanes on a roadway determines how far pedestrians must cross at an intersection and how many conflict points might exist for turning traffic and bicyclists or pedestrians. Efforts have been made to reduce the number and width of lanes through "road diets" that not only reduce the number of lanes but provide space to implement additional pedestrian and bicyclist safety treatments such as adding bike lanes and median crossing islands and reducing travel speed. Read the entire page →
From page 176... ... COUNTERMEASURESROAD DIET/ RECHANNELIZATION 176 Considerations Many factors should be considered while determining the feasibility of a lane reduction, including • Traffic volumes and mix. • Left-turn movements. Read the entire page →
From page 177... ... COUNTERMEASURES 177 Roundabouts are circular intersections designed to eliminate left turns by requiring traffic to circulate around a central island. Roundabouts are typically installed in place of traffic signals to reduce vehicular speeds, improve safety at intersections by eliminating angle and higher-speed collisions to allow more efficient traffic operations, and to reduce operation costs associated with signalized intersections. Read the entire page →
From page 178... ... COUNTERMEASURESROUNDABOUT 178 Complementary Countermeasures Should be installed with the following treatments: • High-visibility crosswalk markings. • Warning sign (MUTCD W11-1, W11-2, W11-15, or S1-1) Read the entire page →
From page 179... ... COUNTERMEASURES 179 Traffic signal timing can impact pedestrian and bicyclist safety. Undue delays for pedestrians and bicyclists may encourage unsafe crossing behavior and could have an overall negative impact on perceived walkability and bicycling convenience. Read the entire page →
From page 180... ... COUNTERMEASURESSIGNAL TIMING 180 Complementary Countermeasures Should be installed with the following treatments: • High-visibility crosswalk markings (for pedestrian signals) Read the entire page →
From page 181... ... COUNTERMEASURES 181 Traffic signals create gaps in the traffic flow to allow pedestrians and other users to cross the street at locations where users would otherwise experience long delays or have difficulties crossing the street safely. Warrants in the MUTCD govern the installation of traffic signals, which are based on the number of pedestrians and vehicles crossing the intersection, among other factors. Read the entire page →
From page 182... ... COUNTERMEASURESTRAFFIC SIGNALS 182 Complementary Countermeasures Should be installed with the following treatments: • High-visibility crosswalk markings. • Curb ramps. Read the entire page →
From page 183... ... COUNTERMEASURES 183 A two-stage left-turn queue box (also known as a Copenhagen‐Left or jug‐ handle turn) designates an area outside of vehicle conflicts for bicyclists to wait for traffic to clear before proceeding in a different direction of travel. Read the entire page →
From page 184... ... COUNTERMEASURESTWO-STAGE BICYCLE TURN QUEUE BOXES 184 Complementary Countermeasures Should be installed with the following treatments: • No Right Turn on Red sign (MUTCD R10-11 series) Read the entire page →
From page 185... ... Abbreviations and acronyms used without definitions in TRB publications: A4A Airlines for America AAAE American Association of Airport Executives AASHO American Association of State Highway Officials AASHTO American Association of State Highway and Transportation Officials ACI–NA Airports Council International–North America ACRP Airport Cooperative Research Program ADA Americans with Disabilities Act APTA American Public Transportation Association ASCE American Society of Civil Engineers ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials ATA American Trucking Associations CTAA Community Transportation Association of America CTBSSP Commercial Truck and Bus Safety Synthesis Program DHS Department of Homeland Security DOE Department of Energy EPA Environmental Protection Agency FAA Federal Aviation Administration FAST Fixing America's Surface Transportation Act (2015) FHWA Federal Highway Administration FMCSA Federal Motor Carrier Safety Administration FRA Federal Railroad Administration FTA Federal Transit Administration HMCRP Hazardous Materials Cooperative Research Program IEEE Institute of Electrical and Electronics Engineers ISTEA Intermodal Surface Transportation Efficiency Act of 1991 ITE Institute of Transportation Engineers MAP-21 Moving Ahead for Progress in the 21st Century Act (2012) Read the entire page →
From page 186... ... TRA N SPO RTATIO N RESEA RCH BO A RD 500 Fifth Street, N W W ashington, D C 20001 A D D RESS SERV ICE REQ U ESTED N O N -PR O FIT O R G . Read the entire page →

From page 109...

... COUNTERMEASURES 109 Appendix: Countermeasure Glossary This Countermeasure Glossary provides supplemental information on each of the countermeasures recommended in this Guide. Each countermeasure located in this appendix provides key information for practitioners to consider when assessing, choosing, refining, and finalizing countermeasures to address specific crash types or safety performance objectives.