Marketplace host Erica Johnson tries to program her GPS while driving. (CBC)

Programming your car's portable GPS while driving is a dangerous distraction, according to a Marketplace investigation, but so far the industry still allows drivers that option.

The Marketplace team decided to test a couple of drivers to see the ease or lack thereof when it comes to programming a Global Positioning System device while driving. Both drivers own GPS units and are familiar with their use but even they had trouble keeping their eyes on the road. Let's just say it's a good thing Marketplace made sure to test them on a quiet road in Pickering, just outside of Toronto, that had been blocked off by police.

"Oh my God, it’s like I can’t spell, for crying out loud," said Pam Kapty, who was trying to enter the address for a restaurant in the CN Tower.

According to safety experts, drivers should not take their eyes off the road for more than two seconds at a time, and the U.S. Society of Automotive Engineers has recommended that programming a GPS take no longer than 15 to 20 seconds in total.

"Every time you look away, that’s another time period that you’ve lost a sense of what’s happening while driving," said Paul Green, a transportation engineer at the University of Michigan's Transportation Research Institute.

Kapty wasn't able to program her unit while driving and after hitting a pylon and wandering over the centre line, she had to give up and pull over.

The use of in-car GPS units has grown in popularity. Between August 2008 and August 2009, 1.3 million units were sold in Canada, up 19 per cent from the previous 12 months, according to the New York-based market research firm NPD Group.

Some are built into the car's dashboard, but the portable devices are installed on top of the dashboard, or even attached to the windshield. There have been some restrictions in the U.S. Wisconsin has banned GPS units from being attached to the windshield, while California limits the placement to the far corners.

Programming a GPS while driving can be a dangerous distraction. (CBC)

In Canada, regulations on GPS devices vary from province to province. In Ontario and British Columbia, it's illegal to program a GPS while you're driving.

But according to a poll commissioned by Marketplace, 47 per cent of drivers admit to programming and driving. The poll, conducted in December by Research Now, questioned 500 GPS owners about their thoughts on the gadget. The survey is accurate to plus or minus 4.4 per cent, 19 times out of 20.

There are no official statistics on how many accidents are the result of GPS distraction. But according to the Marketplace poll, 35 per cent of drivers admitted they had lost concentration or had been distracted by their GPS.

A family in Sault Ste. Marie, Ont., knows first hand the type of tragedy that can occur because of driver distraction.

Shannon Bentley, 25, was killed in October 2008 when a driver slammed into her car after she'd pulled over on the shoulder because of engine problems. The driver had been distracted by his GPS.

"It’s a new toy. It’s new technology," said Shannon's mom, Roxanne Bentley. "They don’t realize what could happen. People are losing their lives over this."

Shannon Bentley was killed in October 2008 near Sault Ste. Marie, Ont., when a driver distracted by his GPS slammed into her car. (CBC)

Safety experts say GPS manufacturers should as a rule lock drivers out to prevent them from programming the GPS if the car is moving. Some built-in brands of GPS do just that, for instance Toyota and many Lexus models. But there are entire chat rooms on the internet devoted to disabling the code that prevents the GPS from being programmed while the car is in motion.

Perhaps for that reason, the after-market GPS industry is keener on letting consumers decide for themselves whether they should pull over while programming.

"If we had 100 per cent foresight, and we knew exactly where we wanted to go 100 per cent of the time, that certainly would be nice. But that’s not always the case," said Steve Koenig, director of industry analysis for the Virginia-based Consumer Electronics Association.

Asked why industry would give so many people the option to do something that’s potentially dangerous, Koenig replied: "I don’t believe it’s potentially dangerous if it's done in a safe way. And this is the key point."

But that answer doesn't sit well with Green.

"From what we've seen, those tasks take too long and they shouldn't be performed while driving. And the system should be designed to lock that out," said Green.

"We [at the Transportation Research Institute] have lots of concerns and that's why there have been rules written. The major problem seems to be that the after-market companies [which make portable GPS devices] don't try to comply with the rules. Most of the [car] manufacturers do."