Pedestrian deaths hit a contemporary low in 2009. One of many unwanted effects of the rampaging reputation of ever-larger automobiles since then: Research analyzing the correlation between pedestrian deaths and ever-larger automobiles. The query of correlation did not start in 2009; here is a research from 2008. Questions of correlation and causality appeared to select up within the information cycle round 2018, when last numbers from the Nationwide Freeway Visitors Security Affiliation put pedestrian deaths in 2016 at their highest degree since 1990. In 2018, NPR reported, “A new study by the Insurance Institute for Highway Safety found that between 2009 and 2016, pedestrian fatalities increased in nearly every circumstance examined. But among all types of vehicles, SUVs had the biggest spike in single-vehicle fatal pedestrian crashes, and crashes were increasingly likely to involve high-horsepower vehicles.” So started common bouts of tales like, “Death on foot: America’s love of SUVs is killing pedestrians,” of politicians asking for pedestrian security rankings on sure automobiles, extra research like, “Pedestrian deaths and large vehicles,” and extra opinion items like, “The Troubling Tie Between Big Cars and Pedestrian Deaths.”
Final 12 months ended with a slew of items on the matter, and we’re starting 2024 with one other set of research outcomes on the subject. Justin Tyndall on the College of Hawai’i’s Financial Analysis Group authored the sooner research talked about above, “Pedestrian Deaths and Large Vehicles.” His new tackle the info, titled “The effect of front-end vehicle height on pedestrian death risk,” examined how excessive the entrance finish of a automobile must be to start to point out an outsized impact on pedestrian deaths. The summary tells the story of the outcomes: “I merge U.S. crash data with a public data set on vehicle dimensions to test for the impact of vehicle height on the likelihood that a struck pedestrian dies. After controlling for crash characteristics, I estimate a 10 cm increase in the vehicle’s front-end height is associated with a 22% increase in fatality risk. I estimate that a cap on front-end vehicle heights of 1.25 m would reduce annual U.S. pedestrian deaths by 509.”
Translating that begins with understanding that nearly 7,400 pedestrians died after being struck by automobiles in 2021; in 2005, that quantity was 3,813 pedestrians. Tyndall says {that a} four-inch rise within the peak of a automobile’s entrance fascia leads to a 22% rise within the danger of pedestrian demise. If regulators capped entrance fascia peak at 49.2 inches, the numbers level to 509 lives being saved yearly within the U.S., practically 7% of 2021’s demise determine.
Tyndall’s paper follows final November’s report by the Insurance coverage Institute for Freeway Security about the identical matter. And if the IIHS findings are correct, it appears 40 inches of auto entrance fascia peak begins to stress the numbers. The IIHS wrote, “Vehicles with hoods more than 40 inches off the ground at the leading edge and a grille sloped at an angle of 65 degrees or less were 45 percent more likely to cause pedestrian fatalities than those with a similar slope and hood heights of 30 inches or less. Vehicles with hood heights of more than 40 inches and blunt front ends angled at greater than 65 degrees were 44 percent more likely to cause fatalities.”
In contrast to the IIHS, Tyndall would not take the angle of the entrance fascia into consideration, the paper explaining, “[The] angle of a vehicle’s hood is generally similar across consumer cars and light trucks. Therefore the proposed method of estimating front-end height should capture the large majority of true variation across vehicles.” All of which feels like there’s going to be extra granular research of heights and slopes — and shortly, automobile weights — earlier than we’re able to put a dividing line on simply how tall a automobile is just too tall.
Lastly, one in all Tyndall’s attention-grabbing findings was that on the common automobile, there is a 2.4-inch vertical rise from the forefront of the hood to the windshield cowl. He writes that the quantity labored on the Toyota Corolla and the Ford F-150. Much more attention-grabbing: This Automotive & Driver piece from 2012 explaining how pedestrian laws can begin off as fractional changes that, in service to proportion and visible design, assist end in bigger automobiles sitting greater up on bigger wheels.