Areas with heavy traffic, road construction, large numbers of pedestrians, or severe weather demand extra attention from a driver. The driver should avoid all possible distractions while in such areas, including cell phone use.

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.

For the first step of a vehicle inspection, you should review the last inspection report on your vehicle, if there is one. The carrier should have repaired any problems noted on the report.

If you must drive in reverse, you should back up slowly and use the mirrors on both sides of your vehicle. Use a helper to monitor your blind spots whenever possible. You and the helper should agree on a signal for "stop."

In rainy weather, roads are often at their most slippery when the rain first begins to fall. Fresh rainwater mixes with oil and grease on the road to form a slick film. As the rain continues, this mixture will eventually wash away.

Backing can be dangerous, so avoid doing it whenever you can. If possible, park in such a way that allows you to pull forward to exit your parking space.

You should make frequent mirror checks to monitor the traffic around you. This should help you notice if surrounding vehicles begin to move into your blind spots.

A trailer tends to swing around, potentially resulting in a trailer jackknife, if its wheels lock up.

If you encounter a distracted driver, make sure to give them plenty of room. Be very careful if you pass their vehicle because the driver may be unaware of your presence and drift into your lane.

Before inspecting the engine compartment, make sure that the parking brakes are on and/or the wheels are chocked. Check the engine compartment before entering the cab and starting the engine.

The easiest way to spot a trailer skid is to use your mirrors. Any time you brake hard, check your mirrors to ensure that your trailer is still in its proper position.

To reduce the chances of driving distracted, you should avoid eating, drinking, or smoking while driving. Anything that diverts attention from the task of driving is a distraction.

Backing up is always dangerous because it is impossible to see everything behind your vehicle. If you must drive in reverse, use a helper, if possible.

In newer vehicles with air brakes, the parking brakes are controlled by a diamond-shaped yellow knob. Pull the knob out to activate the parking brakes and push it in to release them.

Tractors, trucks, and buses with Anti-Lock Braking Systems (ABS) have yellow malfunction lamps located on their instrument panels. Trailers have yellow ABS malfunction lamps on their left side, either on the front or rear corner.

The emergency air line (also known as the supply line) has two functions. The first is to supply air to the trailer air tanks, and the second is to control the emergency brakes on combination vehicles.

If a pre-trip inspection reveals anything unsafe about your vehicle, you must get it repaired. It is illegal to operate an unsafe vehicle.

Driving a combination vehicle usually requires more skill than driving a single vehicle. Combination vehicles are generally longer and heavier than single commercial vehicles.

Before a trip, you should ensure that air reaches all air brakes on all trailers by opening up the rear emergency line and service line shut-off valves to listen for escaping air. Close both shut-off valves before beginning to drive.

Due to their size, doubles and triples cannot be turned suddenly. They require extra care to avoid rollovers when turning.