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CDL · Loading and Unloading

Which of the following must NEVER be loaded with hazmat cargo?

Reviewed by Jordan Morley, Editorial Lead at 247SimpleTests. Written by the 247SimpleTests Editorial Team from the official source material cited on every question.

Correct answer

Class 8 (corrosive) materials in metal containers next to Class 7 (radioactive) materials — and other incompatibility combinations

  1. A Tools and equipment used for the haul
  2. B Standard load straps
  3. C Class 8 (corrosive) materials in metal containers next to Class 7 (radioactive) materials — and other incompatibility combinations
  4. D Empty pallets

Why this is the answer

The Segregation Table (49 CFR 177.848) lists materials that must not be loaded together because they react dangerously with each other. The simplest 'do not load together' combinations include: cyanides with acids (releases hydrogen cyanide gas), oxidizers with flammables (severely worsens fires), and certain radioactive materials with corrosives in metal containers (corrosion of the radioactive container). The table also lists 'distance' requirements where small physical separation is acceptable. Drivers should consult the table for every multi-material load. The shipper is primarily responsible for ensuring loads are compatible, but the driver shares legal responsibility and can refuse to transport an unsafe combination. 'Compatibility' is not a suggestion — incompatible loads have caused fatal incidents.
Source: FMCSA CDL Manual 9.3.2 Segregation

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About this topic: Loading and Unloading

Loading and unloading hazmat questions cover segregation of incompatible materials, securing the load, the no-smoking and engine-off rules, and the special handling for explosives, flammables, oxidizers and poisons. This is one of 10 Hazardous Materials questions on loading and unloading, each with a full explanation on a single study page.

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