Chapter 7: Commercial Licenses
When a CDL Is Required
A Commercial Driver License (CDL) becomes mandatory once you are driving for hire or operating a vehicle above certain weight thresholds — think tractor-trailers, large dump trucks, concrete mixers, and anything hauling hazardous materials. Getting a CDL means passing an additional written knowledge test specific to the vehicle class and a specialized skills test that a standard Class C driving test does not cover.
Endorsements
On top of the base CDL, an endorsement authorizes you to handle something extra — passengers, hazardous materials, tank vehicles, or double/triple trailers, for example. Each endorsement has its own written test, so a driver hauling gasoline in a tanker and a driver operating a school bus are both CDL holders, but with entirely different endorsement histories behind their licenses.