Cargo tanks

Scope

Anyone offering a hazardous liquid or gas for shipment must be familiar with the regulations concerning cargo tanks.

Regulatory citations

• 49 CFR Part 178, subpart J — Specification for containers for motor vehicle transportation

Key definitions

• Cargo tank: A bulk packaging that:
  • Is a tank intended primarily for the carriage of liquids or gases and includes appurtenances, reinforcements, fittings, and closures (for the definition of a tank, see 49 CFR 178.320, 178.337-1, or 178.338-1, as applicable);
  • Is permanently attached to or forms a part of a motor vehicle, or is not permanently attached to a motor vehicle but which, by reason of its size, construction or attachment to a motor vehicle is loaded or unloaded without being removed from the motor vehicle; and
  • Is not fabricated under a specification for cylinders, intermediate bulk containers, multi-unit tank car tanks, portable tanks, or tank cars.

Summary of requirements

Specifications. The cargo tank includes appurtenances, reinforcements, fittings and closures. A cargo tank is not fabricated under a specification for cylinders, intermediate bulk containers, portable tanks, multi-unit tank car tanks, or tank cars.

A cargo tank is permanently attached to or forms a part of a motor vehicle, or is not permanently attached to a motor vehicle but which, by reason of its size, construction or attachment is loaded or unloaded without being removed from the motor vehicle. The definition for cargo tank can be found in 171.8.

Common specification cargo tanks include MC 306, MC 307, MC 312, DOT 406, DOT 407, and DOT 412. The specifications for construction of cargo tanks can be found in Part 178, subpart J of the Hazardous Materials Regulations.

Inspections. Cargo tanks are required to undergo certain tests and inspections. For more information see the ezExplanation Cargo Tank Inspections/Tests.

Marking. Cargo tanks are required to be properly marked and placarded for transport. For information on these topics see the ezExplanations Markings and Placarding.