Drive Smart columnist Tim Schewe.

Drivesmart column: How to make a safe lane change

Preparation for a lane change is critical

By Tim Schewe

I watched a particularly foolish driver the other afternoon who decided to cross over two lanes of traffic in order to prepare for a left turn about a kilometre ahead. This driver zoomed across all the lanes without pause, ending up in the left hand lane about three vehicle lengths ahead of a heavy truck.

To make life really interesting for the truck driver the next thing this driver did after making the lane change was to apply the brakes.

This unthinking driver put the trucker at a disadvantage, forcing his vehicle into a space that was inadequate. Compounding the problem was the brake application at a point where the truck had no place to go and no distance to stop. I don’t think I could have picked a better example of how to make an unsafe lane change.

Three rules for making lane changes:

“151 A driver who is driving a vehicle on a laned roadway

“(a) must not drive it from one lane to another when a broken line only exists between the lanes, unless the driver has ascertained that movement can be made with safety and will in no way affect the travel of another vehicle,

“(b) must not drive it from one lane to another if that action necessitates crossing a solid line,

“(c) must not drive it from one lane to another without first signalling his or her intention to do so by hand and arm or approved mechanical device in the manner prescribed by sections 171 and 172”

That was the mantra drummed into me in driver training:

• Use your mirrors to determine how much space there is around your vehicle. If there is enough space in front and behind to comply with the two second rule, move to the next step.

• Give an adequate signal before you move. Tell everyone around you what you intend to do so that they have enough time to see and prepare.

• Shoulder check before you move. You cannot be sure that your blind spot is empty until you confirm it by looking carefully.

• If all three of the previous steps have been done correctly, it is time to move smoothly into the adjacent lane while maintaining your speed.

Preparation for a lane change is critical. Knowing the state of the traffic around you will help decide whether you should change lanes at all, or if you are turning, how far ahead of the turn you should start moving over to prepare. Your actions should never be a surprise to the traffic around you.

We’ve already learned that you must not make a lane change over a solid line. It is also defensive driving practice to remain in your lane when approaching, passing through or leaving intersections. Drivers entering the highway may want to use the same space that you do.

Making an unsafe lane change may result in a fine of $109. A conviction carries 2 penalty points.

Tim Schewe is a retired constable with many years of traffic law enforcement. To comment or learn more, please visit