Because there are many different types of tanks, each of which with its own specific features, a driver should always consult the operator's manual for information on how to inspect a particular tank.

If your trailer starts to skid while you are braking, you should release the brakes and allow them to begin to regain traction. Once its wheels have regained their grip on the road, the trailer will begin to straighten out and follow the tractor.

The power unit of a placarded vehicle must be equipped with a fire extinguisher with an Underwriters Laboratories (UL) rating of 10 B:C or more.

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.

All trailers and converter dollies manufactured on or after March 1, 1998 must be equipped with Anti-Lock Braking Systems (ABS).

When performing a static leakage test on a double combination vehicle with air brakes, the leakage rate should be no more than 3 psi in one minute. If air leaks from the air brake system at a quicker rate, the vehicle should not be driven because something likely needs to be repaired.

Signal well in advance of a turn so drivers behind you are aware of your intentions. Keep the signal on throughout the turn and turn it off once the turn is complete.

Mirror checks should be a normal part of your scanning routine. It is particularly important to make frequent mirror checks when driving in close quarters.

The service brake system applies and releases the brakes when a driver presses the brake pedal while driving normally.

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.

When performing a static leakage test on a single vehicle with air brakes, the leakage rate should be no more than 2 psi in a minute. If air leaks from the air brake system at a quicker rate, the vehicle should not be driven because something likely needs to be repaired.

A one-way check valve is required to be between an air compressor and the first main reservoir. This valve prevents air from escaping the system if the air compressor develops a leak.

When driving during the winter, it is especially important to make sure the coolant and antifreeze are at safe levels.

You should reduce your speed by about one-third when driving on a wet road. It can be difficult to stop or turn when operating on a slippery surface, so you must adjust your speed to drive safely under such conditions.

If you are unsure of which method is appropriate to use to extinguish a fire, you should wait for firefighters to arrive and let them handle it. This is especially important when dealing with hazardous materials fires.

It is important that all of your vehicle's equipment is in proper working condition before you begin a trip. If a trailer's spring brakes do not release when you push in the tractor air supply control, you should make sure the air line connections are properly attached and sealed.

You should never exceed the speed shown on a "Maximum Safe Speed" sign.

If a hazard requires you to drive onto the shoulder of a road, you should try to keep one set of wheels on the pavement to maintain better control of your vehicle. If possible, stay on the shoulder until your vehicle has come to a complete stop, then pull back onto the road when it is safe to do so.

Roads are particularly slippery when it first begins to rain. The water mixes with oil drippings on the road that have not yet washed away, creating a slippery and dangerous mixture.

You should always apply the parking brake when leaving your vehicle.