A biological hazard, or biohazard, could be a biological substance that poses a threat to the health of living organisms, primarily humans. this might embrace a sample of a organism, virus or poisonous substance which will adversely have an effect on human health. A biohazard might even be a substance harmful to different animals. Recently, infectious diseases are found to be most frequent among activity diseases. Discovery of activity infectious diseases had tons of ripple effects within the field of activity medication and industrial hygiene. activity infections, as well as parasitic diseases, will limit the vary of applied diagnostic and certification procedures solely to diseases induced by unhealthful agents or by exposures occurring within the activity surroundings. In some cases, it becomes tough or maybe not possible to spot the $64000 explanation for patients' complaints. activity biohazards area unit infectious agents or dangerous biological materials that exert harmful effects on workers' health, either directly thorough infection or indirectly through harm to the operating surroundings,