What additional requirement applies to obtaining a hazardous materials endorsement on a CDL?

To obtain a HAZMAT ENDORSEMENT (H or X) on a CDL, the driver must pass a SECURITY THREAT ASSESSMENT (background check) conducted by the TSA (Transportation Security Administration), including FINGERPRINTING. CDL hazmat. This is required because hazardous materials could be used as weapons (security concern after 9/11). The assessment checks criminal history, immigration status, and terrorism watch lists; certain disqualifying offenses bar the endorsement. The driver also must pass the hazmat knowledge test. SECURITY TRAINING is part of hazmat driver requirements. Knowing the TSA security threat assessment/background check requirement for the hazmat endorsement is commonly tested.