Employees who work with hazardous materials must be trained and tested at least once every three years.

Height warnings are often, but not always, posted on low bridges. If you are unsure if you will be able to clear an overhead object, go slowly.

Cargo inside a trailer must be secured appropriately to prevent it from shifting in transit.

Texting and driving is dangerous for everyone on the road. It is illegal to text while operating a CMV.

If you must drive so slowly that you will impede the flow of traffic, you should turn on your four-way flashers to alert drivers behind you (as long as local laws allow the use of flashers).

A maximum posted speed limit is the fastest a vehicle may travel under ideal circumstances. A driver should decrease their driving speed as conditions require. A driver should never exceed the legal speed limit.

Problems to check for when inspecting tires include: air pressure that is too low or too high; using radial and bias-ply tires together; tread depth of less than 4/32 of an inch in major grooves on front tires; and tread depth of less than 2/32 of an inch on all other tires.

In work zones, you should drive at the posted speed limits. Reduce your speed even further when workers are on or near the road.

Problems to check for when inspecting a vehicle's exhaust system include loose, broken, or missing exhaust pipes, mufflers, tailpipes, or vertical stacks; loose, broken, or missing mounting brackets, clamps, bolts, or nuts; exhaust system parts rubbing against fuel system parts, tires, or other moving parts of the vehicle; and exhaust system parts that are leaking.

If the brakes pull to one side or the other when used, it is an indication of brake trouble.

After starting a vehicle's engine, you should see the warning lights and buzzers go out right away. If they remain on, there is something wrong with your vehicle.

There are several reasons why driving at night is more difficult than driving during the day. It is more difficult for drivers to see hazards, the glare of headlights can affect drivers' vision, and there are more fatigued drivers on the road.

When driving, you should frequently check the mirrors on both sides of your vehicle.

Factors that can affect stopping distance include your vehicle's speed, its weight, and how slippery the road surface is.

The shipper of hazardous materials is responsible for packaging, marking, and labeling the materials. They must supply any necessary placards.

It is always a good idea to compare package markings and labels to accompanying shipping papers. Always make sure the shipper has displayed the correct basic description on the shipping paper and has provided the proper labels on the packages.

Baffled liquid tanks are tanks separated by internal bulkheads with holes in them. These bulkheads inhibit front-to-back surge while the holes allow liquid to flow freely between compartments.

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.

There should be at least 4/32 of an inch of tread depth in every major groove on front tires and 2/32 of an inch on other tires. Valve stems should not be cut or cracked. Tire sizes should not be mismatched.

When inspecting your brakes, you should check for cracked drums; shoes or pads covered in oil, grease, or brake fluid; and shoes that are missing, broken, or worn dangerously thin.