A Guide for Reducing Collisions Involving Bicycles (2008) / Chapter Skim
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From page 27... ...
Based on what is known about bicycle-related crashes, the following objectives -- targeted either toward locations where crashes occur or toward the causal factors of crashes -- are most likely to reduce the number and severity of crashes: • Reduce bicycle crashes at intersections • Reduce bicycle crashes along roadways • Reduce motor vehicle speeds • Reduce bicycle crashes at midblock crossings • Improve safety awareness and behavior • Increase use of bicycle safety equipment • Reduce influence of hazards Each of these strategies can be accomplished through a variety of the 23 individual strategies (treatments) presented in Exhibit V-1.
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From page 28... ...
B5. Provide bicycle-tolerable shoulder rumble strips (T)
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From page 29... ...
SRTS programs are comprehensive programs that involve making safety-related changes to the built environment, implementing extensive child bicyclist (and pedestrian) safety education, and increasing traffic law enforcement around schools.
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From page 30... ...
It is particularly difficult to evaluate the impacts of countermeasures on bicyclist crashes for the following reasons: • Bicycle crashes are substantially more rare than vehicle crashes not involving bicyclists, making it difficult to assess impacts at a given location and over reasonable lengths of time.
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From page 31... ...
. Also, compared to other motor vehicles, some trucks have longer stopping distances, limited visibility (e.g., blind spots)
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From page 32... ...
Enforcement of Traffic Laws Well-designed and well–managed law-enforcement programs can have a significant positive effect on highway safety. It is well-established, for instance, that an effective way to reduce crashes and their severity is to have jurisdiction-wide programs that enforce an effective law against driving under the influence (DUI)
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From page 33... ...
The visibility at intersections can be enhanced by improving the sight distance/sight lines near the intersection and/or by improving the conspicuity of traffic control devices at and near intersections. For example, improving the visibility at intersections could involve: • Increasing the sight distance along the approach to an intersection so that drivers have a better view of the geometric and cross sectional features of the intersection; • Clearing sight triangles so that users have better views of vehicles operating on side streets; • Improving the visibility of traffic control devices which could involve removing vegetation or other roadside objects that obstruct the view of signs and signals or improving the conspicuity of traffic control devices (e.g., installing larger signs, additional signal heads, larger signal lenses, or signal backplates)
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From page 34... ...
on minor-road approaches ▪ Strategy 17.1 E5: Install larger regulatory and warning signs at intersections ▪ Strategy 17.1 E8: Provide supplementary stop signs mounted over the roadway ▪ Strategy 17.1 E11: Install flashing beacons at stop-controlled intersections Objective 17.1 G -- Improve driver compliance with traffic control devices and traffic laws at intersections • NCHRP Report 500, Volume 12: A Guide for Reducing Collisions at Signalized Intersections Objective 17.2 C -- Improve Sight Distance at Signalized Intersections ▪ Strategy 17.2 C1: Clear Sight Triangles ▪ Strategy 17.2 C2: Redesign Intersection Approaches Objective 17.2 D -- Improve Driver Awareness of Intersections and Signal Control ▪ Strategy 17.2 D1: Improve Visibility of Intersections on Approach(es) ▪ Strategy 17.2 D2: Improve Visibility of Signals and Signs at Intersections Objective 17.2 E -- Improve Driver Compliance with Traffic Control Devices • NCHRP Report 500, Volume 9: A Guide for Reducing Collisions Involving Older Drivers Objective 3.1 B -- Improve the Roadway and Driving Environment to Better Accommodate Older Driver's Special Needs ▪ Strategy 3.1 B7: Improve lighting at intersections, horizontal curves, and railroad grade crossings A treatment that helps to improve the visibility at intersections which is unique to bicycles and bicycle facilities involves installing bicycle racks near street corners (Zegeer et al., 1994)
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From page 35... ...
Several ways to improve signal timing and detection to better accommodate bicycle traffic include: • Providing an adequate clearance interval • Providing a leading bicycle phase or bicycle-only phase (which will also involve installation of bicycle signals) • Providing sensors that detect the presence of a bicycle (which may also involve marking the roadway to indicate the optimum location for bicycle detection)
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From page 36... ...
Providing a leading bicycle phase or bicycle-only phase requires a separate bicycle signal (Exhibit V-2) to direct bicycle traffic through the intersection and would only be implemented at intersections with marked bicycle lanes or separated paths.
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From page 37... ...
However, it is expected that this type of treatment will increase bicyclist compliance with traffic signals, which should reduce the number of bicycle/motor vehicle crashes that result when bicyclists ride out into an intersection during a red indication, rather than yielding the right of way to motor vehicle traffic on the cross street. While there may be a need to better accommodate bicyclists during the clearance interval, there is also a need to balance operations and safety.
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From page 38... ...
Similar to the traffic signal warrants that are already provided in the MUTCD, development of a bicycle signal warrant or policy that may be used to justify the installation of a bicycle signal would provide credibility to the treatment. For example, the California Traffic Control Devices Committee (CTCDC)
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From page 39... ...
However, long clearance intervals have several disadvantages (Wachtel et al., 1995) : • Cause extra delay to traffic • May encourage motorists to enter the intersection, believing they are protected • May confuse waiting drivers who do not understand why the signal fails to change Similar to extending the clearance interval, providing a leading bicycle phase or bicycleonly phase may cause the intersection to operate less efficiently for motor vehicle traffic.
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From page 40... ...
Finally, agencies may need to develop a formal policy for improving signal timing and detection. Such a policy could involve one or more of the associated issues (i.e., providing adequate clearance intervals for bicyclists, providing a bicycle signal with a lead bicycle phase or bicycle-only phase, or providing bicycle detection)
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From page 41... ...
Data collection costs may be incurred to collect clearance intervals and exposure data. Capital costs may also be incurred for poles, bicycle signal heads, detection hardware, and detection software.
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From page 42... ...
. The primary advantages of having through bicyclists and right-turning motor vehicles cross prior to the intersection include: • Moving this conflict away from the intersection and other conflicts • Enabling the motorist to pass a bicyclist rather than ride side-by-side due to the difference in travel speeds Exhibit V-7 illustrates several signs for bicycle lanes at intersections where the bicycle lanes continue to the left of the right-turn only lanes.
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From page 43... ...
EXHIBIT V-7 Signing for Bicycle Lanes Adjacent to Right-Turn Only Lanes (Chicago DOT, 2002; Caltrans, 2005)
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EXHIBIT V-10 Bicycle Warning Signs (USDOT, 2003) where they are really needed.
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From page 45... ...
by having or creating one or more of the following conditions: • Low traffic volumes (or bike lanes where traffic volumes are medium) • Discouragement of non-local motor vehicle traffic • Free-flow travel for bikes by assigning right of way to the bicycle boulevard at intersections wherever possible • Traffic control to help bicycles cross major streets • A distinctive look and feel such that bicyclists become aware of the existence of the bike boulevard and motorists are alerted that the roadway is a priority route for bicyclists Care should be taken not to overuse traffic signs.
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From page 46... ...
Exhibit V-12 illustrates typical pavement markings for bicycle lanes in the vicinity of intersections along a two-way street, and Exhibit V-13 illustrates typical striping techniques at T-intersections given the presence or absence of painted crosswalks and bus stops. However, the most complicated scenario for marking bicycle lanes at intersections EXHIBIT V-11 (Continued)
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From page 47... ...
SECTION V -- DESCRIPTION OF STRATEGIES V-21 EXHIBIT V-12 Example of Pavement Markings for Bicycle Lanes on a Two-Way Street (USDOT, 2003)
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From page 48... ...
These innovative pavement marking treatments include: • Advance stop lines (or bicycle box) • Combined bicycle lane/right-turn lanes • Colored bicycle lanes
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From page 49... ...
SECTION V -- DESCRIPTION OF STRATEGIES V-23 EXHIBIT V-14 Bike Lanes Approaching Right-Turn-Only Lanes (AASHTO, 1999)
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From page 50... ...
SECTION V -- DESCRIPTION OF STRATEGIES V-24 EXHIBIT V-15 Example of Bicycle Lane Treatment at a Right-Turn-Only Lane (USDOT, 2003)
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From page 51... ...
The box allows bicyclists to get to the head of the traffic queue on a red traffic signal indication and proceed first when the signal indication changes to green. The primary purpose of a bicycle box is to improve the visibility of bicyclists at intersections and to enable bicyclists to correctly position themselves for turning movements during the red signal phase by allowing them to proceed to the front
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From page 52... ...
: • Increasing the visibility of bicyclists by allowing them to move to the front of the queue where they are in full view of motorists on all sides of the intersection • Enabling bicyclists to maneuver to the correct position for turning movements during the red signal phase • Not significantly increasing delay to motor vehicle traffic • Reducing conflicts between turning bicycles and motor vehicles by clearly delineating locations for movements to occur • Providing a buffer between motor vehicle traffic and pedestrian crosswalk The combined bicycle lane/right-turn lane is a standard width bicycle lane that is installed on the left side of a dedicated right-turn lane. A dashed pavement marking divides the bicycle portion and the right-turn portion of the lane.
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From page 53... ...
Several advantages of this type of treatment include (Nabti and Ridgway, 2002; Hunter et al., 2000) : • Improving visibility of bicycle lane at key locations • Warning bicyclists and motorists of especially hazardous areas Pavement guide lines at signalized intersections can also be used to facilitate the movement of left-turning bicyclists (Exhibit V-20)
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From page 54... ...
Proportionally, more bicyclists at intersections with wide curb lanes made motor vehiclestyle left turns with improper lane destination positioning compared to intersections with marked bicycle lanes. In addition, statistical modeling of conflict data showed lower conflict rates for straight through and right-turning bicycles at intersections where the
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From page 55... ...
• There was a problem with motor vehicle encroachments into the box. In 52 percent of the red traffic signal indications, motor vehicles encroached into the box.
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From page 56... ...
Motorists thought the locations were safer with the colored pavement markings in place and that the markings increased motorist awareness of the conflict areas. The primary key to success of marking bicycle lanes at intersections is consistency.
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From page 57... ...
Potential difficulties or disadvantages associated with the combined bicycle lane/right-turn lane include (Nabti and Ridgway, 2002) : • Forcing bicyclists into the adjacent through lane when heavy vehicles are turning right • Bicyclists shifting to the right turn portion of the combined lane if a heavy vehicle is in the through lane • Decreased effectiveness where a right turn island is required EXHIBIT V-22 Signing Associated with Combined Lane (adapted from Hunter, 2000a)
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From page 58... ...
A key process measure is the number of intersections where pavement markings have been improved. Crash frequency and severity, by type, are key safety effectiveness measures.
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From page 59... ...
Appendix 5 provides details related to costs of colored bicycle lanes. Training regarding use of this strategy should be provided in highway agency courses covering the use of traffic control devices.
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From page 60... ...
Strategy A5: Improve Intersection Geometry (T) General Description There are several ways to modify the geometry of an intersection to improve bicycle safety, including: • Reducing the crossing distance for bicyclists • Realigning intersection approaches to reduce or eliminate intersection skew • Modifying the geometry to facilitate bicycle movement at interchange on-ramps and off-ramps • Providing refuge islands and raised medians These geometric improvements are addressed below.
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From page 61... ...
. This type of geometric improvement is related to Strategy 17.1 B16 -- Realign Intersection Approaches to Reduce or Eliminate Intersection Skew in NCHRP Report 500, Volume 5: Guide for Addressing Unsignalized Intersection Collisions and Strategy 17.2 B4 -- Revise Geometry of Complex Intersections in NCHRP Report 500, Volume 12: Guide for Reducing Collisions at Signalized Intersections.
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From page 62... ...
. Exhibit V-27 presents another optional treatment for marking bicycle lanes near interchange entrance ramps, and in this option the bicycle lane is separated from the roadway for a short distance along the channelized roadway in order to loop around and intersect the channelized roadway close to a 90 degree angle (Oregon DOT, 1995)
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From page 63... ...
This strategy is related to Strategy 9.1 A3 -- Construct Pedestrian Refuge Islands and Raised Medians in NCHRP Report 500, Volume 10: Guide for Reducing Collisions Involving Pedestrians.
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From page 64... ...
SECTION V -- DESCRIPTION OF STRATEGIES V-38 EXHIBIT V-27 Bicycle Crossing of Interchange Entrance Ramp where a Bicycle Lane Becomes a Separated Path (Oregon DOT, 1995) • Roadway width is excessive given the available crossing time.
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From page 65... ...
Concerning the expected safety benefits of realigning the roadway, a group of experts concluded from a review of the literature that realigning intersection approaches to reduce or eliminate intersection skew improves motor vehicle safety at unsignalized intersections along two-lane rural highways (Harwood et al., 2000)
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From page 66... ...
Realignment may also negatively affect adjacent properties. Because some of the optional treatments for improving bicycle safety near interchange areas are not necessarily the shortest distance through the interchange area for the bicyclist, some bicyclists may deviate from the bicycle facility.
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From page 67... ...
Attribute Description Technical Attributes Appropriate Measures and Data Associated Needs Organizational and Institutional Attributes Organizational, Institutional and Policy Issues Issues Affecting Implementation Time Costs Involved Training and Other Personnel Needs Legislative Needs Other Key Attributes A key process measure is the number of intersections where geometric improvements were implemented to improve bicycle safety. Crash frequency and severity, by type, are key safety effectiveness measures.
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From page 68... ...
. At signalized intersections with a history of bicycle/motor vehicle crashes resulting from RTOR movements, an analysis of the time of day of the crashes may provide justification for restricting RTOR movements throughout the entire day or during specified hours of the day.
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From page 69... ...
Key safety effectiveness measures include (a) the frequency and severity of bicycle/motor vehicle crashes resulting from all right turn movements at signalized intersections, (b)
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From page 70... ...
(2000) concluded that bicycle accident rates at roundabouts are 15 times those of motor vehicles, and surveys taken from bicyclists indicate that bicyclists find roundabouts significantly more stressful to negotiate than other forms of intersections, particularly on roads with heavy traffic.
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From page 71... ...
: • Avoid bicycle lanes on the outer edge of the circulatory roadway. A 1992 German study focusing on bicycle safety at urban intersections found that including bike lanes or crosswalks on the outside of a "circular intersection" actually created more safety risk in an already dangerous environment than when bicycles simply shared the roadway with motor vehicles.
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From page 72... ...
Attribute Description Technical Attributes Keys to Success Potential Difficulties Appropriate Measures and Data Associated Needs Organizational and Institutional Attributes Organizational, Institutional and Policy Issues Issues Affecting Implementation Time Costs Involved Training and Other Personnel Needs Legislative Needs Other Key Attributes longer history of use so it is reasonable to expect that implementing these recommended approaches will improve bicycle safety at roundabouts in the United States. Because roundabouts are still a relatively new intersection treatment in the United States, new roundabouts are being constructed around the country.
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From page 73... ...
Several other factors that should be considered in determining the need for grade separation include (Minnesota DOT, 1996) : • Traffic volume and traffic mix • Motor vehicle operating speeds • Number of lanes to be crossed (i.e., crossing distance)
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From page 74... ...
Strategy Attributes for Providing an Overpass or Underpass (T) Attribute Description Technical Attributes • Approaching path design • Impact of bicycle traffic on vehicular traffic Another key to success of grade-separated crossings is they must be well-designed.
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From page 75... ...
Roadway facilities that better identify appropriate travel areas for all road users and their expected behavior may provide a safer environment for bicyclist travel along parallel paths and help reduce crashes.
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From page 76... ...
Bike lanes are usually along the right edge of the roadway but may be placed to the left of parking or right-turn lanes. Marked bicycle lanes on roadways should be one-way only and carry bicycle traffic in the same direction as adjacent motor vehicle traffic.
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From page 77... ...
. EXHIBIT V-36 Example of Roadway Cross Sections with Bicycle Lanes (AASHTO, 1999)
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From page 78... ...
Similar in concept to striped bicycle lanes, shared lane markings consist of markings placed in the area of desired bicyclist travel. The markings do not indicate a separated bicycle lane, but instead direct bicyclists to travel outside the car door zone and improve awareness of bicyclists and motorists that they are sharing part of the roadway environment.
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From page 79... ...
Further guidance on the appropriate width of shoulders to accommodate bicyclists on roadways in these situations can be found in FHWA's Selecting Roadway Design Treatments to Accommodate Bicyclists. Paved shoulders tend to result in fewer erratic motor vehicle driver maneuvers, more predictable bicyclist riding behavior, and enhanced comfort levels for both motorists and bicyclists (Harkey et al., 1996)
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From page 80... ...
The presence of the bike lane stripe has also been shown from research to result in fewer erratic motor vehicle driver maneuvers, more predictable bicyclist riding behavior, and enhanced comfort levels for both motorists and bicyclists (Harkey et al., 1996)
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From page 81... ...
Research (Harkey et al., 1996) has shown that paved shoulders tend to result in fewer erratic motor vehicle driver maneuvers, more predictable bicyclist riding behavior, and enhanced comfort levels for both motorists and bicyclists.
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From page 82... ...
The cost of maintaining stripes, shared lane markings, and colored bicycle lanes may be high, but proper selection of paint or colored surface material can minimize these costs. Proper placement of on-road bicycle facilities requires balancing user needs with right-of-way limitations.
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From page 83... ...
It is most cost efficient to create bike lanes during street reconstruction, street resurfacing, or at the time of original construction. • Shared lane markings have significantly lower initial and maintenance costs compared to striped bicycle lanes.
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From page 84... ...
Shared lane markings may also encourage proper placement of the bicyclist within the wide curb lane and will encourage bicyclists to travel in the same direction as motor vehicle traffic. Minimum and maximum design widths for bicycle lanes should be carefully examined.
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From page 85... ...
in the other direction. For more information about contraflow bicycle lanes: BikeSafe Countermeasure Selection System includes a number of case studies of contraflow lanes: (http:// www.bicyclinginfo.org/bikesafe)
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From page 86... ...
portland.or.us/designreferences/bicycle/appenda3.htm) recommend using contraflow bicycle lanes only under the following conditions: • The contraflow bicycle lane provides a substantial savings in out-of-direction travel compared to the route motor vehicles must follow; • The contraflow bicycle lane is short and provides direct access to a high-use destination point; • Safety is improved because of reduced conflicts; • There are no or very few intersecting driveways, alleys, or streets on the side of the proposed contraflow lane; • Bicyclists can safely and conveniently reenter the traffic stream at either end of the section; • A substantial number of bicyclists are already using the street; and • There is sufficient street width to accommodate a full-dimension bicycle lane.
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From page 87... ...
Similarly, bicyclists turning left from contraflow lanes will encounter oncoming traffic unless traffic control devices stop motor vehicles, including those approaching from intersecting lanes. Motorists approaching contraflow lanes may not notice approaching bicyclists because the motorist is expecting and looking for traffic from the other direction.
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From page 88... ...
Attribute Description Organizational and Institutional Attributes Costs Involved Training and Other Personnel Needs Legislative Needs Other Key Attributes Potential Use of Sidewalks The cost of installing bike lane markings (such as for contraflow lanes) is approximately $3,100 to $31,000 per kilometer ($5,000 to $50,000 per mile)
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From page 89... ...
EXHIBIT V-45 Strategy Attributes for Improving Bicyclists' Visibility (T) Attribute Description Technical Attributes Targets Expected Effectiveness Improved lighting targets both bicyclists and motor vehicle drivers.
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From page 90... ...
Attribute Description Technical Attributes Keys to Success Potential Difficulties Appropriate Measures and Data Associated Needs Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved Training and Other Personnel Needs Similarly, estimates from Florida State University (http://www.safety.fsu.edu/ bicyclemanual.html#accidents ) indicate that "nearly 60 percent of all adult fatal bicycle accidents in Florida occur during twilight and night hours even though less than 3 percent of bicycle riding takes place during that time period." The AASHTO Bicycle Guide recommends using average maintained illumination levels of between 5 and 22 lux.
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From page 91... ...
Shared roadway signs typically consist of yellow warning signs with the legend "Share the Road" and a bicycle and car logo (Exhibit V-46)
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From page 92... ...
. Bicycle Route Signage By providing bicycle route signs that identify official bicycle routes and provide additional information about the route, bicyclist travel can be directed to areas that have better facilities, as well as provide both bicyclists and motorists additional information about their expected behavior.
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From page 93... ...
EXHIBIT V-48 MUTCD Standard Bicycle Route Signs (http://mutcd.fhwa.dot.gov/HTM/2003r1/part9/fig9b-04_longdesc.htm) EXHIBIT V-49 MUTCD Recommended Placement of Bicycle Route Signs (http://mutcd.fhwa.dot.gov/HTM/2003r1/part9/fig9b-06_longdesc.htm)
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From page 94... ...
Bicycle route systems may function as a means of identifying potential sites for other types of improvements in order to complete a functional network. For instance, building a bike bridge at a particular location can help complete a route through one part of town; striping bike lanes can help make it work in another.
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From page 95... ...
If used in excess, regulatory and warning signs tend to lose their effectiveness. The ease of signing for bicycle routes can also mean that bicyclists may not view the effort as a major commitment to bicycling.
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From page 96... ...
The AASHTO Bicycle Guide recommends that rumble strips not be used on routes used by bicyclists unless a minimum of 1.2 m (4 ft) of rideable surface remains for the bicyclist (1.5 m [5 ft]
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From page 97... ...
Research is underway in National Cooperative Highway Research Program (NCHRP) Project 17-32 to develop further guidance for the design and application of shoulder and centerline rumble strips as an effective motor vehicle crash reduction measure, while minimizing adverse operational effects for motorcyclists, bicyclists, and nearby residents.
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From page 98... ...
rather than rumble strip patterns that have been designed strictly based upon motorists' needs, it can be expected that bicyclists will experience less vibration when they encounter the bicycle-tolerable rumble strips, resulting in less discomfort and more control over their bicycles, reducing the risk to bicyclists. If bicyclists know that bicycle-tolerable rumble strips are installed along a route, the bicyclists may be more willing to ride along the shoulder, rather than in the travel lane, thus reducing the exposure to motor vehicle traffic.
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From page 99... ...
Strategy Attributes for Bicycle-tolerable Rumble Strips (T) Attribute Description Associated Needs Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved Training and Other Personnel Needs Legislative Needs Other Key Attributes None identified.
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From page 100... ...
In particular, the reader is directed to the following objectives and strategies in the respective guides: • NCHRP Report 500, Volume 10: A Guide for Reducing Collisions Involving Pedestrians Objective 9.1 C -- Reduce Vehicle Speed ▪ Strategy 9.1 C1 -- Implement road narrowing measures ▪ Strategy 9.1 C2 -- Install traffic calming -- road sections ▪ Strategy 9.1 C3 -- Install traffic calming -- intersections • NCHRP Report 500, Volume 5: A Guide for Addressing Unsignalized Intersection Collisions Objective 17.1 H -- Reduce operating speeds on specific intersection approaches ▪ Strategy 17.1 H2 -- Provide traffic calming on intersection approaches through a combination of geometrics and traffic control devices The remainder of this section presents issues specifically related to traffic calming and bicycles. In 1994, FHWA published the National Bicycling and Walking Study, FHWA Case Study No.
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From page 101... ...
EXHIBIT V-54 Trees and Colored Bike Lanes Make a Roadway Appear Narrow (Oregon DOT, 1998)
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From page 102... ...
In particular, the reader is directed to the following objectives and strategies in the respective guides: • NCHRP Report 500, Volume 1: A Guide for Addressing Aggressive-Driving Collisions Objective 4.1 A -- Deter aggressive driving in specific populations, including those with a history of such behavior, and at specific locations ▪ Strategy 4.1 A1 -- Target enforcement • NCHRP Report 500, Volume 5: A Guide for Addressing Unsignalized Intersection Collisions Objective 17.1 H -- Reduce operating speeds on specific intersection approaches ▪ Strategy 17.1 H1 -- Provide targeted speed enforcement • NCHRP Report 500, Volume #TBA: A Guide for Reducing Speeding-Related Crashes on HighSpeed Roadways Objective C -- Improve efficiency and effectiveness of speed enforcement efforts ▪ Strategy C1 -- Use targeted conventional speed enforcement programs at locations known to have speeding-related crashes Objective D -- Reduce Bicycle Crashes at Midblock Crossings Strategy D1: Improve Driveway Intersections (T) Driveway improvements are intended to modify the intersection of driveways and roadways to minimize potential conflicts between bicyclists and motor vehicles.
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From page 103... ...
• Driveway right-of-ways should also be kept cleared of foliage, signs, and other objects that obscure visibility. • Pavement markings may improve conditions for bicyclists at driveway intersections; although skip-striping is typically intended to provide information to motorists about an approaching intersection with a right-turn lane, it might also be considered as a means of informing bicyclists that drivers might turn into the driveway.
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From page 104... ...
Where there is a parking and/or bicycle lane, consideration should be given to designing curb radii tighter than modern guides recommend (e.g., older cities in the Northeast and in Europe frequently have radii of 0.6 to 1.5 m [2 to 5 ft]
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From page 105... ...
Attribute Description Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved Training and Other Personnel Needs Legislative Needs Other Key Attributes None identified. Agencies may need to develop new or revised driveway design, construction, and access management policies.
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From page 106... ...
. EXHIBIT V-58 Effective Access Management Reduces the Number of Conflict Points (Oregon DOT, http://www.odot.state.or.us/techserv/bikewalk/planimag/backgrnd.htm)
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From page 107... ...
. • Motor vehicles are redirected to intersections with appropriate control devices or appropriate assignment of right-of-way.
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From page 108... ...
Attribute Description Technical Attributes Appropriate Measures and Data Associated Needs Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved • Placing concrete barriers down the middle of the road (rather than a raised or landscaped median) effectively prohibits pedestrian crossings.
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From page 109... ...
, and increased use of helmets and other safety-related devices is an often-overlooked technique for reducing collisions involving bicyclists and reducing the severity of injuries from such collisions. Child bicyclists are deemed to be solely at fault 70 to 80 percent of the time in crashes with motor vehicles, while only about 40 percent of adult bicyclists are deemed to be at fault (Hunter et al., 1996)
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From page 110... ...
Specifically, with increasing national diversity, materials should be developed for individuals with different ethnic and/or cultural backgrounds. General Education Resources The FHWA National Bicycle Safety Education Curriculum identifies and prioritizes the specific topic areas that should be addressed for various target audiences and includes a resource catalog with information on training programs that address each of the various topics.
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From page 111... ...
Bike Safe." NHTSA developed the "Bicycle Safety Activity Guide," a collection of educational materials and activities in Spanish and English that teachers, parents, and caregivers can use to teach bicycle safety to children ages 4 to 11. Using trained, adult crossing guards is another fairly simple but effective method of providing correction and education to bicyclists and pedestrians, particularly children traveling to and from school.
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From page 112... ...
Education programs should teach bicyclists the importance of having a bike that fits, maintaining the bike in good condition, and always wearing a helmet when riding. Bicycle safety training programs are based on the premise that behavior by bicyclists contributes to the risk of crashes and injuries, and that this behavior can be changed through training programs.
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From page 113... ...
. Second, several experts feel that bicycle education curriculum should be presented as part of a continuum of traffic safety education that begins in elementary school and ends in high school, where children previously trained in bicycle safety transfer their knowledge and skills to motor vehicle driving skills and safety (Thomas et al., 2005; Stutts and Hunter, 1990)
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From page 114... ...
Education programs and curriculums are different, with different intended audiences. Although many bicycle safety education materials and programs exist, it is important to choose the right program for your particular needs and situation.
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From page 115... ...
Attribute Description Technical Attributes Appropriate Measures and Data Associated Needs Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved Training and Other Personnel Needs Legislative Needs The overall effectiveness of different and age-appropriate bicycle safety education programs should be better evaluated, both to verify the usefulness of these programs and to improve the selection of most appropriate curricula and programs. In general, the appropriate measures for evaluating bicycle safety education programs should include the following: • Changes in behavior • Changes in knowledge • Changes in crashes or injuries Program effectiveness evaluations should compare program participants to a comparable group that did not receive training.
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From page 116... ...
Because helmet laws have been proven to reduce fatalities and serious head injuries, it is especially critical that officers enforce any helmet wearing law in effect, to increase the effectiveness of the law. Although law enforcement officers are trained to make motor vehicle traffic stops for speeding, red-light running, and other dangerous behaviors by motorists, they typically do not receive any special training with respect to bicycle law enforcement.
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From page 117... ...
For communities considering a more aggressive approach to enforcing bicycle traffic laws, the International Police Mountain Bike Association (http://www.ipmba.org) and a growing number of consultants offer training to help police departments understand bicycle law enforcement issues (http://www.witc.tec.wi.us/pgmpages/lawenf/ rlake/bicycle.htm)
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From page 118... ...
Enforcing bicycle laws has the same effect as enforcing other traffic laws: it curtails behavior that may result in injuries and fatalities. This point should be reinforced for law enforcement officers who do not feel that enforcing bicycle laws is worth the effort.
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From page 119... ...
Attribute Description Technical Attributes Appropriate Measures and Data Associated Needs Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved Training and Other Personnel Needs Legislative Needs Other Key Attributes National Strategies Process measures for bicycle-related law enforcement might include the number of warnings and/or citations issued. Performance measures include the number of crashes involving bicyclists at driveways, and bicycle and motor vehicle volume data are needed to represent exposure.
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From page 120... ...
For a comprehensive, state-by-state review on bicycle laws in the United States, visit http://www.helmets.org/mandator.htm.
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From page 121... ...
EXHIBIT V-62 Strategy Attributes for Increasing Use of Bicycle Helmets (P) Attribute Description Technical Attributes Targets Expected Effectiveness Keys to Success Potential Difficulties This strategy targets the behavior of bicyclists.
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From page 122... ...
Attribute Description Technical Attributes Appropriate Measures and Data Associated Needs Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved Training and Other Personnel Needs Helmets are often thought by inexperienced users to be uncomfortable, to mess up rider's hair, or to be too hot. Ongoing advances in bicycle helmet design may enable manufacturers and promoters of helmet use to circumvent obstacles against helmet use such as poor fit and poor air circulation, high cost, and the "uncoolness" of wearing a helmet.
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From page 123... ...
Bicycle lanes, discussed in Strategy B1, provide a consistent and predictable space for bicyclists, making them easier to
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From page 124... ...
These materials are required for most roadway markings such as stop lines and lane markings, so their ability to increase conspicuity is established. Vests and other clothing for bicyclists have been made with retroreflective material.
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From page 125... ...
Efforts to increase use of lights on bicycles should be combined with activities to increase enforcement of laws that require their use. Also, studies of bicycle/motor vehicle nighttime collisions have concluded that bicyclists do not understand the potential benefits of adequate conspicuity.
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From page 126... ...
Attribute Description Technical Attributes Appropriate Measures and Data Associated Needs Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved Over the years, numerous bicycle manufacturers have offered bicycles that included lighting systems. These bicycles have not enjoyed commercial success, so manufacturers only rarely offer products with pre-installed lights.
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From page 127... ...
drainage grates and utility covers. At-grade railroad crossings can cause serious problems for bicyclists.
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From page 128... ...
Exhibit V-64 illustrates two ways that bicyclists can cross railroad tracks at a better angle without swerving into the motor vehicle travel lanes. One solution is to provide a flare near the crossing, and the other solution requires providing a short separated path near the crossing.
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From page 129... ...
Keys to successfully treating irregular surface conditions at railroad crossings are to identify all diagonal crossings of bicycle facilities and prioritize the degree of the hazard. The need for a treatment is based upon the angle of the crossing, the width of the flangeway opening, and the amount of bicycle traffic that uses (or potentially uses)
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From page 130... ...
. Once again, if an agency plans to install a sign that is not an accepted traffic control device in the MUTCD, the agency should follow the provisions outlined in Section 1A.10 of the MUTCD for design, application, and placement of traffic control devices that are not adopted in the most recent edition of the MUTCD.
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From page 131... ...
Attribute Description Technical Attributes Many railroad crossings take a continual beating from both motor vehicle traffic and train traffic. As a result, these crossings become rough and uneven.
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From page 132... ...
Attribute Description Technical Attributes Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved Where it is not practical to eliminate a drainage grate or other surface defect that may cause problems for bicyclists, pavement markings may be used to delineate the area (Exhibit V-70)
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From page 133... ...
For debris or surface irregularities on curves or at intersections, special attention should be paid to areas between typical turning paths and through motor vehicle traffic. These areas often fill with debris and are in typical bicyclist trajectories.
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From page 134... ...
Ruts in the pavement, particularly on intersection approaches, should be ground down to provide a smoother surface through the intersection. • Roadway bicycle signs: Bicycle signs should be maintained in the same fashion as other roadway signs, paying particular attention to bike route signs at decision points, warning signs at special hazard locations, and regulatory signs on popular bike-lane streets.
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From page 135... ...
Attribute Description Technical Attributes Potential Difficulties Appropriate Measures and Data Associated Needs Organizational and Institutional Attributes Organizational, Institutional, and Policy Issues Issues Affecting Implementation Time Costs Involved Training and Other Personnel Needs Legislative Needs Other Key Attributes None identified. It is also key to include maintenance costs and clearly define maintenance procedures in all bicycle facility projects.
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Key Terms
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