Bicycle Safety

Overview

Bicyclists,[1] like motorcyclists, are not safeguarded by occupant protection measures found in passenger vehicles and face comparatively high exposure to injury risks in crashes on the roadway. In the absence of separate bike lanes, trails, or paths, bicyclists may be required to operate foot or low-powered electric bicycles on the roadway with vehicles. Bicyclists are also more susceptible to outdoor elements such as weather and road surface conditions (Reish, 2021). Rising bicyclist and pedestrian fatalities have prompted urgent calls from the National Transportation Safety Board (NTSB) and NSC in recent years (NTSB, 2019; Road to Zero, 2021). The number of bicyclists killed in traffic crashes has been steadily trending upwards since 2010. From 2010 to 2021, bicyclist fatalities ranged from 623 to a high of 966 with a yearly average of 800 (NCSA, 2022; Stewart, 2023). For the last 5 years (2017 to 2021), the yearly average has been 883 people on bicycles killed in police reported traffic crashes (NCSA, 2022; Stewart, 2023). Bicyclists accounted for 2.2% of total traffic fatalities in 2021 (Stewart, 2023).

Characteristics of the bicyclist fatalities during 2021 include (NHTSA, 2023):

• Roadway location: The majority (62%) of bicyclist fatalities took place at non-intersection locations.
• Land Use: Bicyclist fatalities tend to occur in urban areas more than rural areas, with urban fatalities accounting for approximately 85% of bicyclist fatalities. The proportion of bicyclist fatalities occurring in urban areas increased from 69% in 2011 to 85% in 2021.
• Vehicle Type: Collisions with light trucks (which includes SUVs, pickups, and vans) were responsible for the highest proportion of bicyclist fatalities (46%).
• Time/Light condition: Over half (56%) of bicyclist fatalities occur in dawn, dusk, or night-time conditions; the highest proportion (21%) of fatal crashes on weekdays occur from 6 p.m. to 8:59 p.m.; the highest proportion (23%) of fatal crashes on the weekend also occur from 6 p.m. to 8:59 p.m.
• Sex: 86% of the bicyclists killed and 81% of those injured were male.
• Age: The average age of cyclists killed was 49.

Bicyclist injuries remain consistently, disproportionately high. In 2021 an additional estimated 41,615 bicyclists were injured. Over the last 5 years, estimated injury-only crashes averaged about 45,400 yearly.

 

Bicyclist Fatalities, 2007 to 2021

The absolute number of crashes, without a measure of the volume of people riding bicycles, is an imperfect indicator and does not tell the whole story of bicycle safety. For example, while the number of crashes is higher in urban areas, this does not mean that the rate of crashes is high in comparison to the rate in other contexts. An analysis of crash rates that used National Household Travel Survey (NHTS) data to calculate fatality rates based on the estimated number of people riding bicycles identified the most dangerous regions for walking and bicycling and the safest regions for walking and bicycling (Schneider et al., 2017). The study authors concluded that many of the safest regions had central cities that have been nationally recognized for investing in bicycle and pedestrian infrastructure and programs.

Bicycling Trends

People travel by bicycle to work, to school, for social and family/caretaking trips, and for recreation, among other reasons. The growth in use of bicycles, and electric bicycles in particular during the COVID-19 pandemic has led to sharp increases in bicycling in some communities, and has resulted in expanded ranges of trip purposes, abilities, and experience of people riding bicycles on public roadways.

Buehler and Pucher (2021) reviewed available data to assess the impacts of the COVID-19 pandemic on the use of bicycles. Travel monitoring sources such as Streetlight and EcoCounter report an estimated 12% to 16% growth of bicycle use in 2020. Bicycle traffic on many off-road, recreational multi-use trails and greenways grew significantly. However, some locations saw a reduction in bicycling as commuting to work was reduced or where general lockdowns were in place.

Longer-term trends indicate only slight changes in bicycling rates in the United States. According to the National Household Travel Survey, from 2001 to 2017 the overall percentage point change in cycling generally was negligible. Significant shifts in who is bicycling has shifted, however. There was an increase among adults 25 to 64, those with higher educational attainment, and among those living in households without a car or in neighborhoods with higher residential density. There was a decline in cycling rates for children and adolescents 5 to 15, for those living in rural areas or areas with lower population densities, and among those in households with higher car ownership (Buehler et al., 2020).

Estimates from the American Community Survey, conducted by the U.S. Census Bureau, suggest that the number of U.S. workers of all ages who travel to work by bicycle increased from 0.4% of workers in 2000 to an average of 0.6% of workers for the 2008-to-2012 period (McKenzie, 2014). The share of workers that “usually traveled to work” by bicycle increased at a faster rate than any other mode of travel. In 2016 the number of workers who biked to work remained at 0.6% of all surveyed workers (McKenzie et al., 2017). Current American Community Survey data shows that the percentage mode share of people bicycling to work declined to 0.5% by 2020 (U.S. Census Bureau, 2020).

The topic of bicycling volume (sometimes generally referred to as mode share or exposure) is intertwined with safety. The complex and non-linear relationship between crashes and volume highlights the fact that the absolute number of crashes is often an imperfect indicator of danger for people on bicycles, and thus, why strategies focused on increasing mode share and improving safety are often considered in tandem (i.e., Safe Routes to School programs).

The phrase “safety in numbers” describes the phenomenon whereby the risk to an individual bicyclist of being seriously injured decreases as the number of people bicycling increases. A recent meta-analysis of motorist-pedestrian or motorist-bicyclist injury crashes estimated that there is safety in numbers for both pedestrians and bicyclists (Elvik & Bjørnskau, 2017). By their estimate, if the number of pedestrians or bicyclists doubles (100% increase), the increase in crashes is expected to be 41%. A subsequent expanded meta-analysis determined that the safety in numbers effect may be stronger for pedestrians than bicyclists, and the safety benefit may stem from overall increases in numbers of bicyclists and improvements in motorist-bicyclist interactions at the population level (Elvik & Goel, 2019). However, a recent literature review of studies on the subject of “safety in numbers” found that despite numerous efforts to quantify it, the exact mechanism that produces this effect is unclear (Kehoe et al., 2022).

A focus on systematically improving infrastructure in tandem with road users’ safe behaviors is important to increasing population-level safety (measured as a reduction in population-wide fatalities and injuries) and people on bicycles or bicycling mode share. Safety improvements with increases in bicycling will reduce individual risk. A recent resource titled Understanding and Using New Pedestrian and Bicyclist Fatalities is focused on education strategies around newer and innovative bicycle facilities (Jackson et al., 2022).

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