The liver removes alcohol from the body at a fixed rate, so the only way to sober up after consuming alcohol is to allow your body time to remove the alcohol on its own.

Combination vehicles are usually heavier and longer than single combination vehicles. Operating a combination vehicle requires a higher level of driving skill than operating a single commercial vehicle.

If you must back up, it is safest to back toward the driver's side of the vehicle. This way, as the driver, you will have the best possible view of your path of travel.

You should shift your vehicle's transmission into a low gear before staring a downhill grade. Be prepared for gravity to increase your vehicle's speed when traveling downhill.

When driving in reverse, it is always recommended that a driver backs their vehicle toward its left side. This will allow the driver the best possible view of the rear of their vehicle.

If you see a distracted driver, give them plenty of space and maintain a safe following distance.

When inspecting a vehicle, you should verify that your dual tires do not come into contact with one another, or with any other part of the vehicle.

You should test the tractor protection valve by allowing the air supply to properly charge, turning off the engine, then releasing air from the system by pressing the brake pedal several times. The tractor protection valve should move into its emergency position when psi drops to an unsafe level.

Truck tractors with air brakes built on or after March 1, 1997, and other vehicles with air brakes built on or after March 1, 1998, must be equipped with anti-lock brakes.

Be sure to check your mirrors before beginning a drive. Your posture may change day to day and your mirrors may need to be adjusted.

Splitting driving responsibilities with a second driver lowers the chance that either of you will drive while fatigued. You can also reduce the risk of fatigue by avoiding heavy foods and keeping the interior of the cab cool.

To ensure that your vehicle does not roll backward when beginning to move after a stop, you should partly engage the clutch before removing your right foot from the brake pedal.

If the low air pressure warning signal comes on while you are driving a vehicle with air brakes, you should immediately bring the vehicle to a safe stop while you are still able to control the brakes. Inspect and repair the brakes as soon as possible.

When making a left turn, you should wait until you reach the center of the intersection before actually beginning to turn. Due to off-tracking, the left side of your vehicle could hit another driver if you begin turning too early.

Double and triple trailer combinations are more likely to be overturned due to the "crack-the-whip" effect than are other vehicles. Drivers must steer gently when pulling trailers.

Distracted drivers perceive hazards on the road more slowly than drivers who are focused, or they do not perceive hazards at all.

When braking a vehicle equipped with an Anti-Lock Braking System (ABS), you should not brake any differently than you would if driving a vehicle with a different braking system.

Black ice is a thin layer of ice that is clear enough for the road surface to be seen through it. A road covered in black ice may look like it is merely wet. You should be very careful when temperatures are below freezing and the road looks wet.

The added weight of a heavy load will make a vehicle sit lower than usual. A vehicle will often be taller when carrying a light load than when carrying a heavy load. If your vehicle fits under an overpass while carrying a full load, it is not guaranteed that it will fit under the same overpass if it is empty.

Radial and bias-ply tires should not be used together. All wheels on a vehicle should be the same style and equally-sized.