Crash avoidance technologies can assist with driving and reduce crashes, but only if drivers use them. A new study by the Insurance Institute for Highway Safety measured current use of front crash prevention, lane departure (i.e., lane departure warning or lane departure prevention), and speed warning systems (i.e., systems designed to alert the driver when they are traveling above the speed limit, either visually or both visually and audibly).

The study found that almost nine out of 10 drivers of vehicles equipped with lane departure warning and prevention systems now keep them switched on. Seven out of 10 drivers of vehicles that give visual alerts when they exceed the speed limit also keep that feature running.

“These results hint at a growing awareness that crash avoidance systems and other technologies can improve safety,” IIHS President David Harkey said. “They also indicate that automakers’ efforts to increase usage rates have been a success.”

“The results reflect a combination of better designs and a growing acceptance of crash avoidance systems, more generally,” IIHS Research Scientist Aimee Cox, the lead author of the study, added.

The study’s finding of high activation rates for visual speeding alerts, in vehicles that have this technology, is perhaps even more encouraging. These high rates also bolster the results of a recent IIHS survey of drivers that showed 60% would find speeding alerts acceptable.

The researchers found that visual speed warnings were activated in 70% of vehicles. In contrast, systems that gave an audible warning when the driver exceeded the speed limit were only switched on in 14% of the vehicles observed.

Such systems, known as intelligent speed assistance (ISA), use a camera capable of reading posted speed limit signs, a GPS with a speed limit database, or both to identify the speed limit on the section of road the vehicle is traveling. The European Union now requires that all new vehicles to be equipped with ISA systems that at least give visual alerts with either cascading audible or haptic (vibration) warnings.

The technology has great potential because speeding is consistently a factor in over a quarter of U.S. fatalities. However, visual-only alerts can easily go unnoticed, and warnings of any kind will only work if drivers keep the feature switched on.

Selling vehicles with speed warnings enabled, for example, could help encourage use. Setting the audible alerts to kick in at 5 or 10 mph over the speed limit as the default might have a similar effect. Drivers who activated their audible alerts were more likely to have selected a higher threshold than those who used only visual alerts.

Even better, the alerts could be configured to work when the driver exceeds the speed limit by a certain percentage and so that the feature remains effective in residential areas and on other lower speed roads where there are more bicyclists and pedestrians.

“The increased acceptance of lane departure prevention should translate into larger reductions in crash rates,” Harkey said.

The same thing can happen with anti-speeding alerts. Survey results show they are already more popular with drivers than some experts believed possible.