Pedestrian Injury Severity Increases With Height of Vehicles: IIHS

The rising popularity of larger SUVs and trucks in the U.S. has been linked to a higher risk of pedestrian fatalities and injuries in auto accidents.

A new study reveals that the height of a vehicle’s hood significantly increases both the overall risk of pedestrian injury and the severity of injuries that individuals may suffer in an accident with an automobile.

The prevalence of large SUVs on U.S. roads has surged from 30% to 57% between 2010 and 2023. During the same period, the average pickup truck in the U.S. has grown 13% heavier and 7% larger.

The heightened risks associated with these vehicles stem primarily from their elevated front ends, which sit above a pedestrian’s center of gravity, increasing the likelihood of head or torso impacts during a collision. Additionally, the greater height of SUVs and trucks raises the risk of pedestrians being pushed underneath the vehicle, often resulting in severe or fatal injuries.

Research has shown that SUVs and pickup trucks are responsible for a disproportionate number of pedestrian injuries and deaths in auto accidents, with some estimates claiming these vehicles are two to three times more likely to kill a pedestrian in a crash compared to smaller cars.

A recent report from the Insurance Institute for Highway Safety (IIHS) highlights the heightened dangers posed by taller vehicles like SUVs and trucks. According to the research, these vehicles significantly increase the risk of severe or fatal injuries to pedestrians, particularly when traveling at higher speeds.

A study by IIHS researchers Samuel Monfort and Becky Mueller analyzed 202 pedestrian crashes to explore how vehicle speed and front-edge height influence injury risk and severity.

Using crash reports and speed data, the study found that pedestrians struck at 20 mph faced a 46% risk of moderate injury and a 1% fatality risk, while at 35 mph, these risks rose to 86% and 19%, respectively. At 50 mph, the fatality risk exceeded 80%.

The study also revealed that median-height pickup trucks are more dangerous than cars, with an 83% chance of causing moderate injuries and a 62% chance of serious injuries, compared to 60% and 30% for cars.

Additionally, U.S. pedestrians face higher injury risks at lower speeds than those in Europe, likely due to the prevalence of larger, taller vehicles in the U.S.

The study identified 15 mph as the threshold for safe crash speeds, much lower than the common 25 mph residential speed limit. Lowering speed limits in pedestrian-heavy areas or implementing traffic-calming measures like speed cameras and narrower lanes could significantly reduce injuries, according to the findings.

Researchers also emphasized the importance of redesigning vehicle fronts, enhancing automatic emergency braking (AEB) systems, and addressing blind spots caused by taller vehicles to improve pedestrian safety.

Rising Pedestrian Accidents and Injuries

The IIHS findings are similar to those found in a University of Hawai’i study published in February 2024, which linked the height of SUV and truck hoods to an increased risk of pedestrian deaths.

The study revealed that between 2016 and 2021, the average front-end height of vehicles increased by 5%. Full-sized SUVs and pickup trucks were found to have front-end heights 27% to 28% higher than the average compact car.

Additionally, pickup trucks were associated with a 68% increase in pedestrian fatality risk, while full-sized SUVs nearly doubled the likelihood, increasing it by 99%.

These findings highlight the growing risks posed by higher front-end vehicle designs, particularly with the increasing prevalence of full-sized SUVs and pick-up trucks on American roads, emphasizing the urgent need for vehicle design improvements to protect pedestrians.