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Environmental Health and Safety

Biosafety Level Criteria

Laboratory Biosafety Level Criteria

Biosafety in Microbiological and Biomedical Laboratories, 6th Edition
Section IV [pdf]

The biosafety levels are designated in ascending order, by degree of protection provided to personnel and the environment. Standard microbiological practices are common to all laboratories. Special microbiological practices enhance worker safety, environmental protection, and address the risk of handling agents requiring increasing levels of containment.

NIH Guidelines for Research Involving Recombinant or Synthetic Nucleic Acid Molecules, April 2019
Appendix G

The objective of physical containment is to confine organisms containing recombinant or synthetic nucleic acid molecules and to reduce the potential for exposure of the laboratory worker, persons outside of the laboratory, and the environment to organisms containing recombinant or synthetic nucleic acid molecules.  Physical containment is achieved through the use of laboratory practices, containment equipment, and special laboratory design.  Emphasis is placed on primary means of physical containment which are provided by laboratory practices and containment equipment.  Special laboratory design provides a secondary means of protection against the accidental release of organisms outside the laboratory or to the environment.  Special laboratory design is used primarily in facilities in which experiments of moderate to high potential hazard are performed.

Vertebrate Animal Biosafety Levels Criteria

Biosafety in Microbiological and Biomedical Laboratories, 6th Edition (BMBL)
Section V [pdf]

The recommendations detailed below for animal biosafety include work practices, safety equipment, and facilities for experiments with animals involved in infectious disease research and other studies that may require containment. These designated animal biosafety levels provide increasing levels of protection to personnel and to the environment, and are recommended as minimal standards for activities involving infected laboratory animals.

NIH Guidelines for Research Involving Recombinant or Synthetic Nucleic Acid Molecules, April 2019 (NIH Guidelines)
Appendix M

The containment levels required for research involving recombinant or synthetic nucleic acid molecules associated with or in animals is based on classification of experiments in Section III, Experiments Covered by the NIH Guidelines. For the purpose of animal research, four levels of containment are established. These are referred to as BL1-Animals (N), BL2-N, BL3-N, and BL4-N and are described in the following appendices of Appendix M. The descriptions include: (i) standard practices for physical and biological containment, and (ii) animal facilities.

Plant Biosafety Level Criteria

NIH Guidelines for Research Involving Recombinant or Synthetic Nucleic Acid Molecules, April 2019 (NIH Guidelines)
Appendix L

Appendix L-I-A. The principal purpose of plant containment is to avoid the unintentional transmission of a recombinant or synthetic nucleic acid molecule-containing plant genome, including nuclear or organelle hereditary material or release of recombinant or synthetic nucleic acid molecule-derived organisms associated with plants.

Appendix L-I-B. The containment principles are based on the recognition that the organisms that are used pose no health threat to humans or higher animals (unless deliberately modified for that purpose), and that the containment conditions minimize the possibility of an unanticipated deleterious effect on organisms and ecosystems outside of the experimental facility, e.g., the inadvertent spread of a serious pathogen from a greenhouse to a local agricultural crop or the unintentional introduction and establishment of an organism in a new ecosystem.

Appendix L-I-C. Four biosafety levels, referred to as Biosafety Level (BL) 1 - Plants (P), BL2-P, BL3-P, and BL4-P, are established in Appendix L-II, Physical Containment Levels. The selection of containment levels required for research involving recombinant or synthetic nucleic acid molecules in plants or associated with plants is specified in Appendix L-III, Biological Containment Practices. These biosafety levels are described in Appendix L-II, Physical Containment Levels. This appendix describes greenhouse practices and special greenhouse facilities for physical containment.

Appendix L-I-D. BL1-P through BL4-P are designed to provide differential levels of biosafety for plants in the absence or presence of other experimental organisms that contain recombinant or synthetic nucleic acid molecules. These biosafety levels, in conjunction with biological containment conditions described in Appendix L-III, Biological Containment Practices, provide flexible approaches to ensure the safe conduct of research.

Appendix L-I-E. For experiments in which plants are grown at the BL1 through BL4 laboratory settings, containment practices shall be followed as described in Appendix G, Physical Containment. These containment practices include the use of plant tissue culture rooms, growth chambers within laboratory facilities, or experiments performed on open benches. Additional biological containment practices should be added by the Greenhouse Director or Institutional Biosafety Committee as necessary (see Appendix L-III, Biological Containment Practices, if botanical reproductive structures are produced that have the potential of being released.


Additional Containment Guidelines


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