Strategies to Increase Bicyclist Safety

Many same principles discussed in the Pedestrian Safety chapter (pages 8-10) also apply for bicyclists. Countermeasures in this chapter are primarily aimed at improving safety behaviors of bicyclists and drivers through education and enforcement measures, and are organized by bicyclist subgroups:

• Children;
• Adult bicyclists;
• All bicyclists;
• Drivers and bicyclists.

A combination of strategies can be used to develop more focused programs to decrease bicycle crashes and injuries. (For examples of combining strategies, see Brookshire et al., 2016.)

• Increase the use of properly fitted bicycle helmets by all bicyclists, including children and adults, to mitigate head/brain injury in the event of a crash.
• Increase enforcement of helmet laws to increase compliance.
• Increase the conspicuity of bicyclists.
• Reduce vehicle speeds, which allows bicyclists and drivers more time to react and reduces impact forces if crashes do occur.
• Reduce exposure to known risky situations through behavioral and environmental countermeasures (without necessarily discouraging bicycling).
• Reduce distracted riding or driving behaviors (cell phones, headphones, etc.). See the chapter on distracted and drowsy driving for countermeasures targeting drivers.
• Decrease riding or driving while impaired. See the chapter on strategies to reduce alcohol-impaired driving. Some of the countermeasures would be applicable to address any type of impaired roadway use.
• Enact and enforce bicycle friendly laws that facilitate safe, predictable, and efficient bicycling in traffic, and safe driving around bicyclists, to update and fill gaps in existing laws.
• Educate LEOs on enforcement of bicycle-specific laws. Educate the public on any new laws, such as safe passing of bicyclists.
• Increase traffic law compliance by both motorists and bicyclists. Train LEOs in appropriate enforcement strategies. In particular, decrease wrong-way riding, sidewalk riding, and traffic control violations by bicyclists (and motorists); proper nighttime lighting; decrease speeding, cutting off bicyclists, passing too closely, or blocking or driving in a designated bicycle lane by motorists; and decrease distraction and impairment that affects the safety of all road users including bicyclists.
• Educate motorists and bicyclists on required safety behaviors related to specific laws to enhance safe interaction between motorists and bicyclists on the roadway.
• Improve bicycle handling skills for bicyclists of all ages.
• Tailor countermeasures to diverse populations, including groups such as recent immigrants who may not be familiar with U.S. traffic laws, the U.S. traffic environment, may not speak or read English, or may not be literate in their native language.

Additional information about countermeasures involving a comprehensive approach to improving pedestrian safety is provided in NHTSA’s Advancing Pedestrian and Bicyclist Safety: A Primer for Highway Safety Professionals (Brookshire et al., 2016).

Most of the above strategies are covered in this chapter under various descriptions. A few, such as “reduce distracted riding or driving” are not described, because as yet, literature searches do not detect any studies that have evaluated laws or programs aiming to reduce distracted riding. A survey of bicyclist attitudes and behaviors indicates that 21% of bicyclists use an electronic device on at least some of their bicycle trips with 9% indicating they use a device during nearly all their trips (Schroeder & Wilbur, 2013). An observational study of 1,974 bicyclists in Boston found that 31.2% of riders were distracted: 17.7% of the riders were wearing earbuds or headphones and 13.5% had objects or cell phones in their hands or on the handlebars (Wolfe et al., 2016). Currently, there is a lack of information about the impact of distracted bicycling on bicyclist safety (Mwakalonge et al., 2014). Organizations with existing or new training or educational programs might consider including these topics in outreach and educational programs and evaluating how well target audiences respond. Trying new strategies and evaluating them is the only way to gain new knowledge of what works. In addition, emerging technologies may help to combat distractions associated with those technologies. Cell phone applications are now available that have the ability to block incoming calls and texts while the cyclist (or other driver) is in motion.

Engineering and Roadway Design. While not dismissing the importance of vehicle design and the role of the built environment in preventing pedestrian crashes, the countermeasures described in this report relate primarily to educational and enforcement measures aimed at improving the knowledge and behaviors of road users to prevent a crash. However, there is a growing recognition of the importance of road design and the built environment in fostering safer user behaviors. A comprehensive approach that uses a combination of effective engineering, enforcement, and educational measures may have the best chance of achieving desired crash reductions.

Safety in Numbers. Finally, the idea that vulnerable road users’ safety may be improved by increasing the numbers of pedestrians and bicyclists is gaining traction and some empirical support. Research from abroad as well as the United States finds that, although actual numbers of crashes may go up, individual risk of crashes with motor vehicles are often lower as numbers of bicyclists and pedestrians increase (Fyhri et al., 2016; Elvik & Bjørnskau, 2017; Geyer et al., 2006; Jacobsen, 2003; Leden et al., 2000). This relationship may not always be linear. An analysis of bicycle crash data from Minneapolis – St. Paul intersections from 2000 to 2013 found that the probability of a crash increased with greater daily bicyclist traffic volume, until the daily volume through the intersection reached 1,532 bicycles. Crash probability then decreased as daily traffic volume exceeded 1,532 bicycles (Carlson et al., 2018).

In 2009 U.S. transportation officials and researchers took a “scanning tour” (assessing innovative technologies and practices in other countries that could significantly improve highways and highway transportation services in the United States) of Denmark, Sweden, Germany, Switzerland, and the United Kingdom. It reported the concept of “safety in numbers” motivated promotion of increased bicycling and walking in these countries as a safety countermeasure (Fischer et al., 2010). These European countries are committed to driving down the total numbers of bicyclist fatalities and injuries while increasing amounts of bicycling. Encouragement in these countries is done in the context of commitments to comprehensive planning, funding, engineering and design improvements, and maintenance policies to provide safe and connected bicycle networks. The report also documents numerous examples of how these policies are put into practice.

A non-linear relationship between traffic volumes (motorist, pedestrian, or bicyclist) and crashes has been demonstrated (AASHTO, 2010; Bhatia & Wier, 2011; Carlson et al., 2018; Elvik & Bjørnskau, 2017), but a causal mechanism for how increased volumes improve bicyclist safety has not been demonstrated (Bhatia & Wier, 2011; Elvik & Bjørnskau, 2017). This means that crashes do not tend to increase in direct proportion to increases in volume, but absolute crash numbers are still likely to increase (and have increased) with increases in cycling – all else being equal. Additionally, all the studies cited above, and others attempting to characterize volume and safety relationships, are based on cross-sectional comparisons. Other safety factors such as motorist speed, congestion, or law enforcement activity that are unmeasured or have not been accounted for in such studies are likely to influence crashes, making it a challenge to isolate the influence of safety and crashes based on increases in cycling alone. Also, cross-sectional studies cannot easily demonstrate the direction of effect – that is, whether a safer environment comes before the greater numbers of bicyclists or is a result of that increase (Bhatia & Wier, 2011). The underreporting of bicycle crashes undermines the estimates of safety effects, particularly for crashes that led to minor or no injuries (Elvik & Bjørnskau, 2017). It is clear, however, that a focus on improving the environment, both the infrastructure and road users’ compliance with laws and safe behaviors, are important to increasing both population-level safety (measured as a reduction in population-wide fatalities and injuries) and numbers of bicyclists or amounts of cycling. As these two elements – safety improvements and increases in bicycling – occur collectively (or in combination), individual risk, or crash rates, may also be reduced.

---