What defines a biohazard?

The correct definition of a biohazard pertains specifically to materials of biological origin that are capable of posing a risk to human health or the environment, particularly if they have infectious properties. This encompasses a wide range of substances, including but not limited to pathogens, tissues, bodily fluids, and other biological materials. The emphasis on the infective nature of these materials is crucial; anything classified as a biohazard has the potential to cause disease or other adverse health effects.

In contrast, while some medical waste may certainly be considered a biohazard, not all waste from medical facilities automatically falls into this category—hence why the first option is too broad. The third choice describes chemical compounds, which would fall under different regulations concerning hazardous materials, but not biohazards specifically. Finally, the mention of substances that decompose naturally pertains to the category of environmental waste rather than biological hazards, and does not directly relate to the definition of a biohazardous material.