Office of Compliance


Biohazards are biological agents or substances present in or arising from the research or work environment. They introduce or may introduce a hazard(s) to the health of the investigator, worker, or community. Biological agents and substances that cause occupational disease include infectious and parasitic agents; bloodborne pathogens, noninfectious microorganisms; such as some algae, animals and animal products, fungi, plants and plant products; and, yeast. Generally, biohazards are either:

  • infectious microorganisms,
  • toxic biological substances,
  • biological allergens, and/or
  • any combination of the above.

Classes of Biological Agents

Class 1 - Agents of no or minimal hazard under conventional conditions of handling.

Class 2 - Agents of normal potential hazard. This class includes agents which may produce disease of various levels of gravity from unintentional inoculation or injection or other cutaneous means but which are contained by conventional laboratory techniques.

Class 3 - Agents concerning special hazard or agents imported into the United States which require a Federal permit for importation. This class includes pathogens which require distinctive conditions for containment.

Class 4 - Agents that require the most rigorous containment conditions because they are extremely hazardous to individuals involved with the laboratory and/or may cause serious epidemic disease. Class 3 agents imported into the United States for the intent of using them in entomological experiments or when other entomological experiments are conducted in the same laboratory area, are included in this class.

Class 5 - Foreign animal pathogens that are barred from the United States by law or whose importation is restricted by U.S. Department of Agriculture ("USDA") policy.

If you have any questions about Biosaftey at MTSU, please do not hesitate to call Environmental Health and Safety at 494-7725.