CFR49 Volume 2 Parts 100-177 Transportation 2020

CFR Title 49 - Transportation (Code of Federal Regulations) is the principal set of rules and regulations issued by the Departments of Transportation and Homeland Security regarding transportation and transportation related security.
Volume 2, Parts 100 to 177 covers Chapter 1 -- Pipeline and Hazardous Materials  Safety Administration, Department of Transportation. 
Subchapter A == Hazardous Materials and Oil Transportation.
Subchapter B -- Oil Tranportation
Subchapter C -- Hazardous Materials Regulations