New Hampshire CDL Permit Test - Double

Every combination vehicle has two air lines: the service line and the emergency line.

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.

Be cautious when driving near people who are working on a disabled vehicle on the side of the road. They may be focused on the repair and not paying attention to nearby traffic.

Always change lanes slowly and smoothly. If you did not see drivers who are already using the lane you wish to occupy, this will give them a chance to get out of your way or honk their horns to alert you. Always signal before changing lanes.

If your vehicle gets stuck on railroad tracks for any reason, you should immediately exit the vehicle and walk away from the tracks. Contact the proper emergency authorities.

You should not brake while making a quick turn to avoid a hazard. Doing so could cause your wheels to lock and make your vehicle skid out of control.

Pre-trip inspections should be conducted in the same way every time. This will reinforce the steps, making it less likely that you will forget to inspect something important.