Biological agents are known to produce infectious, allergenic, toxic and carcinogenic reactions in workers. Bio-hazards include microorganisms, arthropods, allergens, protein allergens, plants such as fungi, lichen, ferns and other invertebrate animals. Bio-hazards occur in medical settings, industrial settings, sewer and water treatment facilities, remote work locations, and within numerous other work environments. Understanding, evaluating, and planning for control of bio-hazards, reduces worker injury and infection.