CDL Hazardous Materials Endorsement (HME)Communication RulesEasy

A driver is transporting a shipment of UN1072, Oxygen, compressed, Class 2.2, in a cargo tank. The cargo tank has a capacity of 3,000 gallons. Which of the following statements about the placarding of this vehicle is correct?

  1. AA 'DANGEROUS' placard is required instead of a specific hazard class placard.
  2. BA Class 2.1 (Flammable Gas) placard is required due to the oxygen's oxidizing properties.
  3. CA Class 2.2 (Non-Flammable Gas) placard is required on all four sides.
  4. DNo placards are required because oxygen is not considered a hazardous material in bulk transportation.
Show answer & explanation

Correct answer: C. A Class 2.2 (Non-Flammable Gas) placard is required on all four sides.

UN1072, Oxygen, compressed, is a Class 2.2 material. When transported in bulk (like a cargo tank), it requires a Class 2.2 (Non-Flammable Gas) placard on all four sides of the vehicle, regardless of quantity, as it is a Table 1 material.

Why the other options are wrong

  • A. A 'DANGEROUS' placard is only used for certain mixed loads meeting specific criteria, not for a single bulk hazardous material that has a specific hazard class placard.
  • B. Oxygen is Class 2.2, not Class 2.1 (Flammable Gas). Its oxidizing property is a subsidiary characteristic, but the primary hazard class is 2.2.
  • D. Oxygen, compressed, is definitely a hazardous material and requires placarding in bulk quantities.

Oxygen Placarding

UN1072, Oxygen, compressed, is a Class 2.2 (Non-Flammable Gas) and requires a Class 2.2 placard on all four sides of a bulk packaging or vehicle.

  • Class 2.2 (Non-Flammable Gas).
  • Table 1 material: placard any quantity in bulk.
  • Placards on all four sides of the vehicle/container.

Memory trick: Oxygen's 'Two Two' class means 'Placards for You'!

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