New rules for construction zones on Alberta highways require contractors to cover speed reduction signs when there aren't any workers on site and if there aren't any safety hazards.

When workers and hazards aren't present, speeding fines and demerits won't be doubled, Transportation Minister Brian Mason announced Tuesday.

Fines will continue to be doubled when construction workers are on site, Mason said.

"There's confusion now because you've got these speed zones that are being enforced and there's no construction happening on Sundays, for example," Mason said at a news conference in Edmonton.

"They're supposed to be covered, but they're not. So that's where the confusion is. This eliminates confusion."

The government is also limiting the length of highway lane closures. Under the new rules, they are now limited to a maximum of three kilometres, in most cases.

Drivers will also have more warning and time to reduce their speed when required.

The new rules are already in effect, and were created with the goal of balancing safety and traffic flow. Alberta Transportation will monitor construction sites to ensure maintenance contractors are abiding by them, Mason said.

Transportation Minister Brian Mason said the rules will help with the flow of traffic through construction zones. (Peter Evans/CBC)

He said he has heard from people who are frustrated when there are speed reductions or lane closures for no apparent reason.

"If there are no safety hazards, lane closures and speed reductions often don't make sense," he said. "In fact, they can lead to problems with traffic congestion or being tailgated when you're obeying the speed limit, but the driver behind you is pushing for you to speed up.

"With these changes, Albertans can have confidence that the lane closures and speed reductions they will encounter on the highway network this year will actually be necessary."

When speed reductions are necessary, contractors can use portable rumble strips and electronic speed displays. Those tools are already in use in some highway construction zones on a trial basis, Mason said.

Contractors are eligible for safety bonuses between $500 and $5,000 if their construction zones are well managed. Failure to follow the new rules could lose to the loss of the bonus, or a maximum penalty of $25,000 and a project shutdown for repeat infractions.