Almost 9 out of every 10 commuters routinely conduct other activities while driving. And some of those activities pose an even greater threat than texting while driving. Eighteen percent of their multi-tasking time is spent reading emails, with a further 9.5 percent spent answering those emails. 

Nearly 9 percent of commute multi-tasking time is spent reading (by looking at text, not via audio). And commuters spend just under 4 percent of their drive time videoconferencing with colleagues or business contacts. 

These are the findings of a new and disturbing study led by Harvard researcher Thomaz Teodorovicz. Teodorovicz and his team set out to learn how much of their driving time commuters spend multi-tasking, and what those additional activities are. To find out, they recruited 400 knowledge workers who commute and asked them to fill out time use surveys, as well as answer questions about their commuting activities. Their answers should cause you concern as a driver, and even more so as a boss if any of your employees commute to their jobs.

87 percent multi-task while driving.

The researchers were surprised to learn that the commuters multi-tasked 87 percent of the time that they were behind the wheel. "We were expecting to see some multitasking in the car, but honestly not to the extent reported in the survey," Harvard professor of business administration and study co-author Raffaella Sadun said in an account of the findings. And Sadun suspects it could be even more common that the study suggests, since some multi-tasking respondents may have been unwilling to admit to this potentially dangerous behavior.

Deaths from car accidents were dramatically up last year, reaching a 16-year high, according to the National Highway Traffic Safety Administration. There are multiple reasons for this increase, but driving while multi-tasking is a growing problem. Texting while driving is bad enough, but at least many phone systems are designed to help drivers cope with their texts while keeping their hands on the wheel and their eyes on the road. Android phones in driving mode, for example, automatically read incoming texts out loud and invite drivers to compose a response in speech-to-text. Email software may lack similar features though, meaning that motorists who read and answer emails while behind the wheel are probably putting themselves and others at risk. The same goes for reading, browsing social media, videoconferencing, and most of the other things study participants report doing while driving.

The study's authors say it's especially critical to address these behaviors now, as cars with partial self-driving abilities will become more widely available. But, they note, for the foreseeable future, self-driving cars will not be completely autonomous and will require a human driver to take control of the car after periods of self-driving, or whenever road conditions arise that automated driving can't handle. "The driver must be able to switch their visual attention away from the non-driving task back to driving, understand the context of the driving task (from traffic situation, to the weather, to the driver's target destination), and take physical control of the vehicle," the studies authors' note. And, they say, commuters may have as little as 10 seconds to accomplish this switch. Given these realities, it's in everyone's best interest if the other tasks they do while driving don't demand too much visual attention or use of their hands.

Your employees are driving distracted.

Of course, most commuters today don't have cars that drive themselves at all, even briefly. So doing anything that requires your eyes to focus away from driving is taking a serious risk. You may be smart enough not to do this. But if you have employees who commute to their jobs by car, the research suggests that 9 out of 10 of them are answering emails, reading, or doing other tasks while driving. You can't stop this behavior, but you can discourage it, for example by communicating to employees what sort of work while driving is appropriate, such as returning phone calls, and which isn't. It may also help to set a policy, for example, that no one is expected to respond to emails until after they arrive at the office.

Whatever you do, when you're on the road, especially during rush hour, stay aware that the drivers around you probably are multi-tasking. So keep alert. It may be more dangerous out there than you think.