49 CFR 383.93 - Endorsements.
(1) In addition to passing the knowledge and skills tests described in subpart G of this part, all persons who operate or expect to operate the type(s) of motor vehicles described in paragraph (b) of this section must pass specialized tests to obtain each endorsement. The State shall issue CDL endorsements only to drivers who successfully complete the tests.
(i) Passenger (P);
(ii) School bus (S); and
(iii) Tank vehicle (N).
(1) Double/triple trailers;
(2) Passenger vehicles;
(3) Tank vehicles;
(4) Used to transport hazardous materials as defined in § 383.5, or
(5) School buses.
(1) Double/Triple Trailers - a knowledge test;
(2) Passenger - a knowledge and a skills test;
(3) Tank vehicle - a knowledge test;
(4) Hazardous Materials - a knowledge test; and
(5) School bus - a knowledge and a skills test.