When driving during the winter, it is particularly important that your tires have adequate tread. You need a tread depth of at least 4/32 of an inch in every major groove on the front tires, and at least 2/32 of an inch on the back tires. Check the tread depths by using a gauge.

There are two indicators that determine when you need to shift into a higher gear. One indicator is the engine speed (rpm). You should read your vehicle's manual to learn its rpm range and shift up when you reach the top of that range. The other indicator is road speed (mph). You should learn which speeds each gear can accommodate, then keep an eye on the speedometer and shift up as needed.

When the shipper packages hazardous materials, they certify that the package has been prepared according to Hazardous Materials Regulations (HMR). Unless a package is clearly unsafe or noncomplying with HMR, you may accept the shipper’s certification concerning the proper packaging of a material.

If a substance is being transported in a reportable quantity, the shipper must display the letters "RQ" on the shipping paper and package.

At times when visibility is low, you should turn your headlights on to the low beam setting. If you are having a difficult time seeing others, they are probably having a difficult time seeing you.

While inspecting a coupling, you should go under the trailer and look into the back of the fifth wheel. Ensure that the fifth wheel jaws are secured around the shank of the kingpin.

Always turn on your four-way emergency flashers if you must park on the side of the road. This is especially important when traveling at night.

There may be a delay of a few seconds between the sound of a tire failing and the time that the vehicle is affected by the tire failure. Because of the short delay, a driver may initially believe that the sound came from another vehicle.

Hazardous materials placards must be at least 10 and three-quarter inches square.

Be sure to inspect your vehicle before driving. Never drive a tank vehicle with open valves or manhole covers.

Always downshift before entering a curve. Decreasing your speed before entering the curve will allow you to maintain better control over the vehicle throughout the curve.

You should always make sure that your vehicle will be able to stop within the area of the road that you are able to see. This means that you must slow down whenever conditions reduce visibility.

Rollovers can happen when a combination vehicle is turned too quickly. To help prevent the risk of rollover, it is important to keep the vehicle's center of gravity low by loading cargo as close to the ground as possible.

If the letter “G,” for "Generic," is written in Column 1 of a shipping paper, the technical name of the associated hazardous material must also be listed.

If a shipping paper describes both hazardous and non-hazardous materials, the hazardous materials must be distinguished in one of three ways. They must be entered first on the shipping paper, highlighted in a contrasting color, or marked with an "X" in a column titled "HM."

Shippers must retain a physical copy or an electronic image of hazardous materials shipping papers for a minimum of two years after the materials are accepted by the initial carrier. For hazardous waste, this increases to three years.

Skids caused by acceleration can usually be corrected by taking your foot off of the accelerator. If you are on an especially slippery surface, you may also need to push the clutch in.

Combination vehicles need more space on the road than other commercial vehicles because they are longer and need more space to turn and stop. It is especially important to properly manage space when you are operating a combination vehicle.

Reduce your speed as you approach a railroad crossing. Remember that you will not necessarily be able to hear a train, and don't assume that signals will warn you of its approach. Never try to outdrive an approaching train at a railroad crossing.

Rollovers happen when an operator turns too fast. Drivers should be sure to slow down before entering turns and curves, especially when transporting a fully-loaded rig.