According to a recent study from the Queensland University of Technology, using hands-free calling while driving — often assumed to be a safer alternative as it allows both hands to stay on the wheel — may be just as distracting as making a regular phone call.

The study placed drivers in a simulator, and monitored how they reacted to various real-world stimuli, like a pedestrian crossing the street, while driving with a handheld phone, a hands-free phone or no phone.

The study found that drivers on the phone, regardless of whether handheld or hands-free, took 40% longer to react than drivers not making a call of any type. Lead author Dr. Shimul Haque told QUT news that this difference would be “enough to kill pedestrians in the city,” and would be “disastrous” on the freeway.

The moral is, regardless of what kind of phone call you’re making, it will be more distracting than having a conversation with a passenger. As Haque told QUT news, “The non-driver can alter their dialogue based on the driving environment, for example stop talking when approaching a complex driving situation,” illustrating that passengers are responsive enough to adapt to situations in real time, whereas a caller on the other line remains in the dark.

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