When do you adjust your mirrors?
A. During the pre-trip inspection
B. From inside the cab
C. When Driving
Answer: A. During the Pre-trip inspection
Adjusting your mirrors should always be done before any movement of the truck. The only way it checked safely, is to view when the trailers are straight. Make sure your mirrors see each part of the truck.
Always be aware of the traffic around you and the status of your tractor and trailers by regularly checking your mirrors.
When checking your mirrors after you are on the road, look for any vehicles on both sides and your back end. This way, in case of an emergency, you can tell if there needs to be an immediate lane change. For blind spots, watch for vehicles that are moving into your area of non-vision.
Also use your mirrors to watch your tires and open cargo if you are carrying any. A tire fire can be spotted quickly if you are watching your mirrors closely.
When a lane change is needed, always look at your mirrors and make sure no vehicles are along side you or coming up into your blind spot. Same with turns, merges, and tight turns.
Once you have signaled, check your mirrors again so that you can verify that no vehicles have moved into your blind spot. Check again when you start changing lanes and then again when the lane change is complete.
STATE OF UTAH, Department of Public Safety Driver License Division. March 2009. Section 6, Combination Vehicles, Page 2-11