LONDON, Ont. -- More tandem trailers could be coming to Ontario’s 400-series highways.

The provincial government is beginning consultations that could lift a key restriction on what are also referred to as long-combination vehicles.

Ontario Truck Driving School president Gus Rahim says there's a good reason for increasing the number of tandems on the road. "Right now there's a big shortage of drivers. That's the biggest problem any company's having right now."

One key limitation currently in place for tandems in Ontario is that they can't be used on highways in Toronto and Ottawa during the morning and afternoon rush hours.

The Ministry of Transportation is conducting a review that could see that regulation dropped, arguing the change would have both environmental and economic benefits.

Rahim agrees it would be beneficial. "Running a truck with two trailers, obviously it's going to be able to pull, almost like running two-for-one."

St. Thomas resident Karen Rojas is a frequent Highway 401 commuter and worries about the safety of having more double-trailer units on the highways.

"Driving normally, the highway is pretty heavy already. To have all those trailers going, it is concerning, for families especially," she says.

There are a number of restrictions on double-trailer units that will remain in place. They can’t exceed the weight limits put on traditional multi-axle tractor-trailers. They also must have enhanced braking and stability control systems.

Rahim says a decade-long pilot project on Ontario highways has been encouraging.

"The accident rate is actually less than a tractor-trailer," he says.

Currently, training for long-combination vehicle drivers is overseen by trucking companies. Rahim believes the province may want to consider creating a training curriculum that all companies must abide to further ease concerns about safety.