Which of the following is NOT a characteristic of Hazard Class 6 materials?

Hazard Class 6 materials are primarily categorized into two main types: toxic substances and infectious agents. The defining features of this class include the potential to cause harm through exposure, whether that exposure is through inhalation, ingestion, or skin contact.

Flammable solids, liquid poisons, and military agents all fall within the various categories of Hazard Class 6 due to their potential to cause toxic effects. Flammable solids are substances that can ignite easily and contribute to toxic exposure when burned. Liquid poisons are designed to be harmful or fatal upon contact or ingestion and are classic examples of toxic materials. Military agents, which include chemical warfare agents, are specifically classified as hazardous due to their intended harmful effects.

On the other hand, non-flammable gases are not classified under Hazard Class 6. They typically do not pose a toxic risk in the same manner as the other examples listed. Non-flammable gases may belong to other hazard classes such as the class for gases (which includes flammable and non-flammable gases) but do not specifically relate to toxicity in the way that Hazard Class 6 does. Hence, identifying non-flammable gases as outside the scope of Hazard Class 6 highlights their distinct safety considerations compared to the other substances mentioned.