HAZMAT CDL Practice Test 2025 - Free CDL Practice Questions and Study Guide

A placard is required for hazardous materials to ensure awareness and proper handling during transportation. Specifically, placards are mandated for certain categories of materials defined under federal regulations, including materials classified under Division 4.3, which pertains to materials that are known to emit flammable gases when they come into contact with water.

This requirement exists regardless of the quantity being transported. The intent is to provide visual notification to handlers, emergency responders, and the public about the potential hazards that are present, which can significantly enhance safety measures. Each division and class of hazardous materials has specific placarding requirements based on the nature of the material and the associated risks involved, so Division 4.3 materials require placarding even if the amount is small.

So, the reason that this choice is correct lies in the regulatory framework which mandates placarding for specific hazardous materials, particularly for the safe transport and handling of substances that pose a risk, ensuring that everyone involved is aware of the potential dangers.