What are Endorsement Codes and when do I need them on my New York CDL?

Endorsements are necessary for certain commercial driving requirements as follows:

(T) DOUBLE or TRIPLE TRAILERS.

(P) PASSENGER. For vehicles which are designed to carry 16 or more people (including the driver); or those which carry 15 or less people (including the driver) transporting children to or from school and home regularly for compensation.

(N) TANK VEHICLES. For vehicles designed to haul liquids or liquefied gases in bulk in permanently mounted tanks or portable tanks rated at 1,000 gallons or more. (H) HAZARDOUS MATERIALS. To carry hazardous materials in amounts requiring placards.

(X) Endorsement code designating a Tank (N) vehicle that carries Hazardous Materials (H).