Florida CDL Permit Test - Double

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 confronted by an aggressive driver, it is most important to get out of their way, if possible. Do not make eye contact with the driver, as doing so could provoke them. Do not let them provoke you with their actions.

A wig wag is a type of low air pressure warning device in an air brake system. It drops a mechanical arm into the driver's view when the air pressure in the tanks falls below 60 psi.

More than half of all accident-related truck driver deaths are a result of truck rollovers. To help prevent a rollover, be sure to load cargo low to the ground and centered on your rig. Take corners slowly and carefully.

To avoid becoming fatigued on a long trip, you should take a break after every 100 miles or two hours of driving. Driving through the night, or during any other time when you would normally be asleep, raises the danger of fatigue.

The controlled braking method for emergency stops involves applying the brakes as hard as you can without locking the wheels. Keep steering wheel movements small when braking in this way.

A broken exhaust system can allow poisonous fumes to enter a vehicle's cab or sleeper berth. Be sure to regularly check your exhaust system for defects.