The rating system requires safeguards that vehicles with partial automation should employ to help drivers stay focused and not treat these systems, such as Tesla's Autopilot and Volvo's Pilot Assist, as self-driving cars, an IIHS press release said.
Currently there are no self-driving cars available to consumers.
"We are worried that these systems are advertised to do certain things, such as drive hands-free and perhaps become disengaged from driving," IIHS President David Harkey said. "There is a message being conveyed to consumers that perhaps these systems can do more than they are intended to."
Vehicles will receive a rating of either "good," "acceptable," "marginal" or "poor." A "good" rating requires that a car monitors whether drivers keep their hands on the steering wheel and whether they look at the road. It also requires that automated lane changes be initiated by the driver, among other things.
The systems must use many alerts to remind the driver of these criteria, and if the driver fails to respond, the vehicle should slow to a crawl or stop, the press release said.
The most common criteria that cars currently on the market fail are monitoring the hands and automated lane change, Harkey said. Many automobiles even market for drivers to use partial automation without holding the steering wheel, he said.
Some other vehicles available to consumers have more egregious faults, even allowing for drivers to use partial automation without wearing a seat belt, Harkey said.
But most of these problems should not be hard to solve.
"For some of these things, they are fixes that can be implemented quickly through software," Harkey said, "We are encouraged that the automakers will address some of these problems rather quickly."
While these requirements cannot force the driver to focus, they allow the driver to be able to take over control quickly if needed, IIHS said.
One of the most publicized crashes involving partial automation was in 2018, when a Tesla Model X driver was distracted playing a cellphone video game while Autopilot was engaged. Hopefully, these safeguards will prevent similar crashes from occurring, IIHS said.
The main goals of these new criteria are not only to set a standard for safety but to change how automakers and customers talk about partial automation. It is not just the job of the automaker to market these systems more clearly, Harkey said, but the driver must use them safely, too.
"We hope to educate consumers in what these systems can and cannot do," Harkey said. The driver "still has a shared responsibility to work with the technology to make sure that they are monitoring these systems and to be the primary individual responsible for what happens with regards to safety."
IIHS expects to issue the first set of ratings sometime this year, but supply chain issues have made vehicles difficult to obtain for testing.
Consumer Reports weighs in
Consumer Reports, an influential organization that tests vehicles, said research suggests human drivers are less likely to pay attention to automated tasks, even when they know the automation isn't perfect.
Its testing found flaws in Tesla, BMW and Subaru's driver monitoring systems, it said. The three automakers did not immediately comment.
Initially, only Ford and General Motors will earn additional points in its 2022 vehicle ratings next month for driver monitoring systems, the consumer organization said.
"Only GM and Ford prevented a driver from using active driving assistance if they stopped looking at the road," it said.
In 2020, the National Transportation Safety Board criticized Tesla's lack of safeguards in a fatal 2018 Autopilot crash in California involving a driver playing a word-building game on his phone during the fatal trip.
NTSB Chair Jennifer Homendy praised the new IIHS rating program as "a meaningful step" towards more informed consumers and safer roads.
Reuters contributed to this report.