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CDL:

Commercial Driver's License (CDL)

A CDL is required to drive any of the following vehicles:

• Any combination of vehicles with a gross combined weight rating (GCWR) of 26,001 or more pounds, providing the gross vehicle weight rating (GVWR) of the vehicle being towed is in excess of 10,000 pounds.
• Any single vehicle with a GVWR of 26,001 or more pounds, or any such vehicle towing another not in excess of 10,000 pounds.
• Any vehicle, regardless of size, designed to transport 16 or more persons, including the driver.
• Any vehicle required by federal regulations to be placarded while transporting hazardous materials.

Regional:

Regional Route

Usually refers to a driver hauling freight within one particular region of the country. You might be in the "Southeast Regional Division" or "Midwest Regional". Regional route drivers often get home on the weekends which is one of the main appeals for this type of route.

OTR:

Over The Road

OTR driving normally means you'll be hauling freight to various customers throughout your company's hauling region. It often entails being gone from home for two to three weeks at a time.

DOT:

Department Of Transportation

A department of the federal executive branch responsible for the national highways and for railroad and airline safety. It also manages Amtrak, the national railroad system, and the Coast Guard.

State and Federal DOT Officers are responsible for commercial vehicle enforcement. "The truck police" you could call them.

Dm:

Dispatcher, Fleet Manager, Driver Manager