Which of the following is a biological hazard?

A biological hazard is any biological substance that poses a threat to the health of living organisms, particularly humans. Pathogens, which include viruses, bacteria, fungi, and other microorganisms, are classic examples of biological hazards because they can cause disease and infection. In laboratory settings, pathogens may be present in samples or cultures, and handling them requires specific safety protocols to prevent exposure and contamination.

On the other hand, chemicals found in the lab, like reagents or solvents, are considered chemical hazards, as they can pose risks through toxicity, flammability, or reactivity. Heavy machinery is related to physical hazards, as it can cause injury through mechanical actions. Similarly, sharp objects are also classified as physical hazards due to their potential to cause cuts or puncture wounds. Thus, the distinction lies in the nature of the threat: pathogens directly affect biological systems, making them a clear biological hazard.