A biological hazard, or biohazard, may be a biological substance that poses a threat to the health of living organisms, primarily humans. this might embody a sample of a being, virus or poisonous substance that may adversely have an effect on human health. A biohazard may even be a substance harmful to alternative animals. The term and its associated image area unit usually used as a warning, in order that those probably exposed to the substances can understand to require precautions. The biohazard image was developed in 1966 by Charles Baldwin, associate degree environmental-health engineer operating for the Dow Chemical Company on the containment merchandise. It is utilized in the labeling of biological materials that carry a major health risk, as well as infective agent samples and used hypodermic needles. The biohazard image was developed by the Dow Chemical Company in 1966 for his or her containment merchandise. in line with Charles Baldwin, associate degree environmental-health engineer United Nations agency contributed to its development: "We needed one thing that was unforgettable however purposeless, therefore we tend to may educate folks on what it means that." In a commentary he wrote for Science in 1967, the image was bestowed because the new customary for all biological hazards ("biohazards"). The article explained that over forty symbols were entailed by Dow artists, and every one of the symbols investigated had to fulfill variety of criteria.