Which of these is NOT considered a physical hazard of chemicals?

The understanding of physical hazards in the context of chemicals focuses on properties that can cause physical harm or represent a risk of injury. This includes characteristics such as being explosive, flammable, or unstable, as these properties fundamentally pertain to how the chemical behaves under certain conditions, potentially leading to physical harm.

Toxicity, although a critical and serious concern, pertains more to health hazards rather than physical hazards. Toxic substances can lead to adverse health effects upon exposure, but they do not inherently possess risk characteristics like explosion or flammability that result from their physical properties. Therefore, toxicity is classified more under health hazards since it directly affects the human body's physiology upon contact or ingestion, rather than representing a physical risk in its intrinsic behavior.