Human-centred design is key to road safety, says UNSW study

Signs and signals must be easy to see, read, and understand. Photo: Shutterstock.
Signs and signals must be easy to see, read, and understand. Photo: Shutterstock.

I'm not going to argue that reality is an illusion because that creates the wrong idea about what I'm trying to say. But, as that earlier story highlighted - specifically via The Monkey Business Illusion, look it up - our perception of the physical world around us is incomplete. And as the researchers behind that demonstration say, "we are missing a lot of what goes on around us," and "we have no idea that we are missing so much."

So if we aren't able to see what is there even in plain sight, think about how hard it is to see what we need to see when it's obscured, or too small to be legible, or worst of all, our attention has been drawn away by something else that we don't need to see or think about while we are driving.

That brings us to the point that the University of NSW made early in August 2021 when they sent out a statement under the headline of "Human-centred design is key to reducing distraction on roads."

Their spokesperson on the issue, Emeritus Professor Michael Regan from UNSW's School of Civil and Environmental Engineering who is a psychologist specialising in transportation human factors, said that traffic control devices, including destination signs, warning signs and traffic lights, need to be designed from a human-centred perspective to be effective.

"Our road and transport environment is designed to help us to get from point A to point B. However, there is a fine line between what should be capturing our attention to assist us along that journey and what is a risk of being a distraction," he said in the statement.

"For example, things such as advertising billboards along highways draw the driver's attention to whatever is being promoted in the ad. But at the same time, they are a source of distraction and may instead draw the driver's attention away from things that are critical for safe driving, such as being focused on the road ahead."

He noted that distractions can come from inside the vehicle or from outside the vehicle, and "Research has shown that approximately 70 percent of distractions are within the vehicle," he said.

Whether that distraction was from devices and gadgets that are part of the vehicle itself, or portable items that you should never be using when driving, "if you take your eyes off the road for two seconds, it's been shown that you double your risk of a collision. Any longer than two seconds, and the risk of a crash increases exponentially."

Tying this back into my original point, if we already miss so many things even when we think we are paying attention, it's no surprise we have an even less complete picture of the environment we're in if we're not constantly looking at what actually matters, thus significantly increasing the likelihood of a crash.

As for what we should be looking at, professor Regan says that for any traffic control device to be effective it must be easy to see, easy to read, and easy to understand.

"Some traffic lights or signs aren't obvious to drivers because they're hidden behind a tree or there's something blocking it. This encourages drivers to adopt compensatory visual scanning strategies to try to see them, which takes their eyes off the road for longer than is necessary."

So for a good design, "To capture the attention of the driver, signs must not have anything obstructing the messaging, so that it is visible to the driver, and the messaging must be crystal clear."

Another concept that professor Regan highlighted is "Road users who are cognitively distracted, for example, when talking on their mobile phone about something complex or emotional, may see a traffic light change colour but not respond to it. That's what we call inattentional blindness; it's the look-but-fail-to-see phenomenon, and it's an issue for drivers and pedestrians too."

As for the solution for road authorities, "Drivers and other road users will continue to be prone to distraction, fatigue and other human conditions. However, there is much that can be done, through good human-centred design, to enhance their safety and prevent crashes," professor Regan concluded.

This story Human-centred design key to road safety, says UNSW study first appeared on The Canberra Times.