People in the following states have to visit their DMV for fingerprinting and application: Florida, Kentucky, Maryland, New York, Pennsylvania, Texas, Virginia and Wisconsin Everyone else can use the TSA HME online application process via IdentoGo. In states that are AAMVA Best Practices compliant you can take the test at any time, even if you only have a CLP for up to 6 months before you have your licence and/or threat assessment. Your CDL expiration date will typically be tied to your HME expiration date.
I'm pretty sure Texas uses IdentoGo. They are contracted with someone for the fingerprinting part anyway.
It doesn't matter what vendor they use for the live scan, you still have to stat the process at the DMV at those states. Here are the Texas steps TxDPS - Hazardous Materials Endorsement Note the TSA site instructions: HAZMAT Endorsement You cannot "complete the entire process in person at an application center" if you are from those states.
That's the way it works in TN. Fingerprints/Background check, receive letter from TSA, go take test at DMV.
Read and heed. Doing one first, then the other can save you $40+ as opposed to doing both HAZMAT and TWIC at the same time. Check with whatever agency to see which to do first.