A backover crash occurs when a vehicle backs into a pedestrian or bicyclist, often when exiting a driveway or parking spot, according to the National Highway Traffic Safety Administration (NHTSA). These crashes typically are at low speeds and exclude crashes that involve multiple vehicles or vehicles that back into objects.

Government databases generally only record crashes on public roads; however, this is not where most backover crashes occur. While no federal data system collects information on all backover crashes, relevant information can be gleaned from a review of NHTSA data, hospital emergency department records, death certificates, and media sources. NHTSA estimates that nearly 200 deaths and about 7,000 injuries occur in backover crashes yearly. Because these sources may not capture all of the deaths and injuries, Congress has directed NHTSA to develop a database of injuries and deaths in nontraffic events involving motor vehicles. This will further help estimate the extent of backover crashes.

Young children, especially toddlers (2 and younger), and older people (70 and older) are most likely to be injured or killed in a backover crash. According to NHSTA's 2006 Report to Congress on backover crashes, 38 percent of the 183 deaths in backover crashes in 1998 were children younger than 5 and 27 percent were people older than 70.

Most backover incidents occur in driveways and parking lots, not on public roads. A review of child pedestrian deaths in Australia from 1996 to 1998 showed 86 percent of drivers in driveway crashes were members of the struck child's family or family friends.¹

Minivans, SUVs, and pickup trucks are involved in more backover crashes than cars.¹ These vehicles typically have larger blind spots and sit higher off the ground than cars, making it more difficult for drivers to see children and smaller objects near the rear of the vehicle.

Technology used in parking aid systems might one day be adapted to reduce the risk of backover crashes. Radar and ultrasonic-based parking aid systems are designed to detect objects near vehicles' rear bumpers and warn drivers of their proximity during parking maneuvers. However, current systems do not reliably detect people, especially small children. Rear parking camera systems also hold promise, but current systems are designed as parking aids and typically do not have a large enough field of view to see people quickly approaching the vehicle's path from the side. In addition, lenses that offer a wider field of view often have distorted images, and all camera systems have degraded view when the lens is covered with rain, snow, ice, or road dirt.

Ultrasonic and radar systems use sensors mounted in the rear bumper to determine the distance of objects or people from the vehicle. Audible signals (e.g., chimes) or visual signals (e.g., dash warning lights) indicate when an object has been detected. These signals may intensify (i.e., get louder or flash more rapidly) as the distance between the vehicle and the object or person narrows. Camera-based systems display the area behind the vehicle on a screen, which usually is mounted on the instrument panel as part of a navigation system.

In 2006, NHTSA tested 8 sensor-based and 3 visual (1 camera-based and 2 auxiliary mirror) systems. All of the sensor-based systems could detect a moving adult within the system-established detection zone when the vehicle was stationary. The size of the person had an effect on detection performance. Most systems' detection zones did not extend near enough to the ground (not lower than18 inches) to detect a crawling infant.¹ All of the systems showed some inconsistency in detecting people in the vehicle blind spot and also showed areas where children were not detected. Sensor-based systems typically only can detect people directly behind the vehicle. None of the systems tested had large enough detection zones to completely cover the blind spot on the vehicle.

The rearview camera systems displayed nearly the entire rear blind zone when the view was unobstructed (i.e. view not diminished by inclement weather, sun glare, or dirty lenses). The camera systems had clear images of the area behind the vehicle and allowed drivers to recognize a person. However, NHSTA noted that camera effectiveness depended on drivers reversing slowly enough (not more than 2 mph) to allow for adequate reaction time. The agency concluded that more research was needed to determine how drivers would use and react to camera systems before knowing if they would achieve full potential.

Two mirror systems tested by NHTSA had substantial areas behind the vehicle where people could not be seen, and the images were subject to distortion due to the convexity of the mirror.¹ Auxiliary mirrors are often placed on vertical rear windows or are mounted inside the vehicle near or on the rear pillars.

Technology to detect people behind vehicles is not fully developed and perhaps will never be 100% effective so it is likely drivers will always need to be vigilant. The national "Spot the Tot" campaign, developed by Safe Kids Utah, encourages drivers to walk completely around a vehicle before getting in and to roll down windows to hear what's happening near the vehicle before backing. It's also suggested to teach children to move away from a vehicle when started and to have them stand in full view of the driver when backing.

No. However, to reduce backover crashes Congress passed a law in February 2008 that requires NHTSA to amend the safety standards to expand the required field of view of motor vehicles. Congress also directed NHTSA to ask manufacturers to develop systems on automatic transmission vehicles that require the brakes be engaged before they can be shifted out of park for all vehicles sold after Sept. 1, 2010.¹