X
Washington Endorsement
CDL endorsement code X
Combined H + N endorsement for drivers who haul hazardous materials in tank vehicles.
What it covers
The X endorsement combines HazMat (H) and Tank (N) in one stamp. It is required to transport hazardous materials in a tank vehicle — for example, fuel tankers and chemical haulers.
Federal requirements
- Pass both the HazMat and Tank knowledge tests (typically combined).
- Submit fingerprints and complete a TSA Security Threat Assessment.
- Be a U.S. citizen or lawful permanent resident.
- Complete ELDT (federal) for first-time H component.
- Renew every 5 years.
Source: 49 CFR §383.93
Fees
TSA STA fee (~$86.50) plus state test fees.
How to study
- Use the HazMat and Tank sections of your state CDL manual together.
- Focus on emergency response procedures, placarding, and surge dynamics.
- Practice both the HazMat and Tank practice tests inside your state's page.
Take the Washington practice test
State-specific practice tests live inside each state hub. Pick yours:
FAQ
Is X just H plus N?
Yes — but it's typically tested and issued as one combined endorsement so you don't hold two separate codes.
How often does the TSA background check need to renew?
Every 5 years, regardless of which endorsement (H or X) you hold.