• General knowledge -  Must be taken and passed by all CDL applicants no matter what class of CDL or type of endorsement's are needed.
  
  
• Air Brakes - Must be taken and passed if any vehicle you drive has air brakes.
  
  
• Combination - Must be taken and passed if you drive combination vehicles requiring a Class "A" CDL.
  
  
• Passenger -  Must be taken and passed by all bus driver applicants. An additional written test may be required if transporting children to and from school.
  
  
• Hazardous Materials - Must be taken and passed if you transport hazardous materials requiring "placarding". A threat assessment (background check) is also required every time
  you renew your license. You will be required to take the hazmat test and do a background check.

Threat assessment information (background check)
For most States use hazprints.com All others are listed below.
The 12 States listed below do NOT use HAZPRINTS.COM
Click on your State below for more information.
Florida, Kentucky, Maryland, Mississippi, New Mexico, New York,
Pennsylvania, South Carolina, Tennessee, Texas, Virginia, Wisconsin

• Doubles / Triples - Must be taken and passed if you pull double or triple trailers.
  
  
• Tanker - Must be taken and passed if you drive a "tank" with a capacity of more than 1000 gallons.