Blind Spots and Mirror Setup: Staying Safe Around Heavy Trucks

Tractor-trailers have large blind spots on every side. Learn how to set your mirrors, check your surroundings and share the road with confidence.

A loaded tractor-trailer can be more than twenty metres long, and the driver cannot see everything around it. The areas where other vehicles disappear from the mirrors are often called no-zones, and they are where many avoidable collisions happen. Professional drivers manage them through careful mirror setup and constant scanning, while other motorists can help by understanding where they should not linger.

The four main blind spots

• Directly in front of the cab: because of the hood and the driver's seat height, small vehicles can vanish right ahead of the bumper.
• Directly behind the trailer: there are no rear-view mirrors that show what is immediately behind, so tailgating a truck is dangerous.
• Along the driver's side: a narrower zone that extends back from the door.
• Along the passenger side: the largest blind spot, which can stretch across multiple lanes and a long way back.

Setting your mirrors correctly

Adjust your seat first, then your mirrors, and never the other way around. Flat mirrors give an accurate view of distance, while convex mirrors widen the field of view. Set them so that you can see the side of your own trailer along the edge of the mirror, with the rest of the glass showing the lane beside you. Check that you can see the rear tires on both sides, as this helps you judge turns.

Scanning habits

Mirrors alone are not enough. Good drivers check them every five to eight seconds, glance ahead and behind and use a smooth scan pattern instead of staring at one view. Before changing lanes, they signal early, check both mirrors twice and confirm the space is clear. Taking the time to look twice is part of professional driving.

Turning with a long vehicle

Trucks often swing wide to the left before turning right so the trailer can clear the corner. This leaves a gap that other drivers sometimes try to fill. A driver may also need to use more than one lane, so give them room and be patient.

Tips for other motorists

• If you cannot see the truck driver's face in their mirror, they probably cannot see you.
• Pass on the left, and complete the pass quickly rather than lingering beside the trailer.
• Do not cut in front of a truck. They need much more distance to stop than you do.
• Stay well back, which also gives you a better view of the road ahead.

What we teach

Our instructors spend a large part of in-cab training on mirror setup, lane changes, turns and observation techniques. Students learn to treat blind spots as a risk to be managed instead of a surprise. These habits make a real difference during the road test, where examiners watch closely for mirror checks and scanning.