Drivers who operate trucks with a gross vehicle weight of 26,001 pounds or who operate a vehicle carrying hazardous materials or oversized loads need a commercial driver's license (CDL). To qualify for a CDL, applicants must have clean driving records, pass written tests on rules and regulations, and demonstrate that they can operate commercial trucks safely. A national database permanently records all driving violations committed by those with a CDL, and issuing authorities reject applicants who have suspended or revoked licenses in other states.
Although many states allow 18-year-olds to drive trucks within their borders, a driver must be at least 21 years of age to cross state lines or get special endorsements. Regulations also require drivers to pass a physical examination every 2 years. Physical qualifications include good hearing, at least 20/40 vision with glasses or corrective lenses, and a 70-degree field of vision in each eye. They must also be able to distinguish between colors on traffic lights. Drivers must also have normal use of arms and legs and normal blood pressure. People with epilepsy or diabetes controlled by insulin are not permitted to be interstate truck drivers.
Federal regulations require employers to test their drivers for alcohol and drug use as a condition of employment and require periodic random tests of the drivers while they are on duty. Drivers may not use any controlled substances, unless prescribed by a licensed physician. A driver must not have been convicted of a felony involving the use of a motor vehicle or a crime involving drugs, driving under the influence of drugs or alcohol, refusing to submit to an alcohol test required by a state or its implied consent laws or regulations, leaving the scene of a crime, or causing a fatality through negligent operation of a motor vehicle. All drivers must be able to read and speak English well enough to read road signs, prepare reports, and communicate with law enforcement officers and the public.