Key Terms & Definitions


Development and implementation of administrative policy, work practices, facility design, and safety equipment to prevent transmission of biological agents to workers, other persons, and the environment.

Biosafety Level (BL or BSL)

A description of the degree of physical containment being employed to confine organisms containing recombinant DNA molecules and to reduce the potential for exposure of laboratory workers, persons outside of the laboratory, and the environment. In Appendix G of the NIH Guidelines, these are graded from BSL-1 (the least stringent) to BSL-4 (the most stringent). These levels are also detailed extensively in the BMBL.

Biological Safety Officer (BSO)

An individual appointed by an institution to oversee management of biosafety risks. The NIH Guidelines require that a BSO be appointed when the institution is engaged in large-scale research or production activities, or in research requiring containment at BSL-3 or BSL-4. The duties of the BSO are described in section IV.B.3 of the NIH Guidelines.

Biosafety in Microbiological and Biomedical Laboratories (BMBL)

A document published by the CDC and NIH detailing recommendations for work with a variety of infectious agents in various laboratory settings. It describes combinations of standard and special microbiological practices, safety equipment, and facilities constituting BSL-1-4, as well as giving recommendations for various specific infectious agents.


Protection of high-consequence microbial agents and toxins (or critical information pertaining to those agents or toxins) against theft or diversion by those who intend to misuse them.

Bloodborne Pathogens

Pathogenic microorganisms that are present in human blood and can cause disease in humans. These pathogens include, but are not limited to, hepatitis B virus (HBV) and human immunodeficiency virus (HIV).


The presence or the reasonably anticipated presence of blood or other potentially infectious materials on an item or surface.


The use of physical or chemical means to remove, inactivate, or destroy bloodborne pathogens on a surface or item to the point where they are no longer capable of transmitting infectious particles, and the surface or item is rendered safe for handling, use, or disposal.


In the context of the NIH Guidelines, an institution is any public or private entity, including federal, state, and local governments.

Institutional Biosafety Committee (IBC)

An institutional committee created according to NIH guidelines to review research involving recombinant DNA. The role of IBCs has evolved over time, and many committees also review other forms of research that entail biohazardous risks as part of their institutionally assigned responsibilities.

NIH Guidelines for Research Involving Recombinant DNA Molecules

A document created in 1976 by the National Institutes of Health that outlines principles for the safe conduct of research employing recombinant DNA technology. The NIH guidelines detail practices and procedures for the containment of various forms of recombinant DNA research, for the proper conduct of research involving genetically modified plants and animals, and for the safe conduct of human gene transfer research. As a “living” document, it is periodically revised to keep pace with the changing state of science.

Office of Biotechnology Activities (OBA)

The NIH office responsible for developing, implementing, and monitoring NIH policies and procedures for the safe conduct of recombinant DNA activities, including human gene transfer.

Personal Protective Equipment (PPE)

Specialized clothing or equipment worn by an employee for protection against a hazard. General work clothes (e.g., uniforms, pants, shirts, or blouses) that are not intended to function as protection against a hazard are not considered to be personal protective equipment.

Recombinant DNA Advisory Committee (RAC)

An NIH advisory committee whose principal role is to provide advice and recommendations to the NIH director on 1) the conduct and oversight of research involving recombinant DNA, including the content and implementation of the NIH Guidelines, and 2) other NIH activities pertinent to recombinant DNA technology. A major element of the committee’s role is to examine the science, safety, and ethics of clinical trials that involve the transfer of recombinant DNA to humans.

Recombinant DNA Molecules

According to current NIH Guidelines, molecules constructed outside of living cells by joining natural or synthetic DNA segments to DNA molecules that can replicate in a living cell, or molecules that result from their replication.

Responsible Official

A facility official with the responsibility and authority to ensure that the requirements of Title 42, Code of Federal Regulation, Part 73, are met.

Select Agent

Specifically regulated pathogens and toxins as defined in Title 42, Code of Federal Regulation, Part 73, including pathogens and toxins regulated by both Department of Health and Human Services and U.S. Department of Agriculture (i.e., overlapping agents or toxins).


The use of a physical or chemical procedure to destroy all microbial life, including highly resistant bacterial endospores.

Universal Precautions

An approach to infection control. According to the concept of universal precautions, all human blood and certain human body fluids are treated as if known to be infectious for HIV, HBV, and other bloodborne pathogens. All definitions are from the Center for Disease Control and Prevention (CDC), the National Institutes of Health (NIH), or the Occupational Safety and Health Administration (OSHA).