The States and Washington, DC are the backbone of Commercial Driver's Licensing. Pocket Guide to Large Truck and Bus Statistics.Analysis Analysis, Research, & Technology.Safe Driver Apprenticeship Pilot (SDAP).Update My USDOT Number and/or Authority.Apply for a New USDOT Number and/or Authority.Main Menu - Registration - Registration 2 Daily Register / Certificates / Letters.ADA Requirements for Over-the-Road Bus Companies.