How are hazardous materials classified within the TDG framework?

Hazardous materials are classified within the TDG framework primarily by using subclasses based on their safety characteristics and risks. This classification system ensures that materials with similar dangers are treated consistently and that appropriate safety measures and regulations are applied based on the specific hazards they may pose during transportation.

By categorizing hazardous materials into specific subclasses, authorities can establish clear guidelines for handling, packaging, and transporting these goods. Each subclass reflects the intrinsic properties of the materials, such as their toxicity, flammability, reactivity, or other hazardous traits. This organized approach is essential for ensuring safety in the transportation of dangerous goods and helps prevent accidents and incidents during transit.

The other choices, while potentially relevant in a broader context, do not align with the standardized and safety-focused methodology used in the TDG classification system. For instance, classifying materials by their physical appearance, distance of transport, or origin of production does not provide the necessary information regarding the associated risks and safety requirements that are paramount in the handling of hazardous materials.