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Federal Register / Vol. 59, No. 127 / Tuesday, July 5, 1994 / Notices 
is the office within the NIH that is 
responsible for: (i) Reviewing and 
coordinating all activities relating to the 
NIH Guidelines, and (ii) performing 
other duties as defined in Section IV-C- 
3. 
Section I-D— 4. The ‘Recombinant 
DNA Advisory Committee” is the public 
advisory committee that advises the 
Department of Health and Human 
Services (DHHS) Secretary, the DHHS 
Assistant Secretary for Health, and the 
NIH Director concerning recombinant 
DNA research. The RAC shall be 
constituted as specified in Section IV- 
C-2. 
Section I-D-5. The “NIH Director” is 
the Director of the National Institutes of 
Health, or any other officer or employee 
of NIH to whom authority has been 
delegated. 
Section I-D-6. "Deliberate release” is 
defined as a planned introduction of 
recombinant DNA-containing 
microorganisms, plants, or animals into 
the environment. 
Section II. Containment 
Effective biological safety programs 
have been operative in a variety of 
laboratories for many years. 
Considerable information already exists 
about the design of physical 
containment facilities and selection of 
laboratory procedures applicable to 
organisms carrying recombinant DNA 
(see section V-A). The existing 
programs rely upon mechanisms that 
can be divided into two categories: (i) A 
set of standard practices that are 
generally used in microbiological 
laboratories; and (ii) special procedures, 
equipment, and laboratory installations 
that provide physical barriers that are 
applied in varying degrees according to 
the estimated biohazard. Four biosafety 
levels are described in Appendix G. 
These biosafety levels consist of 
combinations of laboratory practices 
and techniques, safety equipment, and 
laboratory facilities appropriate for the 
operations performed and are based on 
the potential hazards imposed by the 
agents used and for the laboratory 
function and activity. Biosafety Level 4 
provides the most stringent containment 
conditions. Biosafety Level 1 the least 
stringent. 
Experiments involving recombinant 
DNA lend themselves to a third 
containment mechanism, namely, the 
application of highly specific biological 
barriers. Natural barriers exist that limit 
either: (i) The infectivity of a vector or 
vehicle (plasmid or virus) for specific 
hosts, or (ii) its dissemination and 
survival in the environment. Vectors, 
which provide the means for 
recombinant DNA and/or host cell 
replication, can be genetically designed 
to decrease, by many orders of 
magnitude, the probability of 
dissemination of recombinant DNA 
outside the laboratory (see Appendix I). 
Since these three means oi 
containment are complementary, 
different levels of containment can be 
established that apply various 
combinations of the physical and 
biological barriers along with a constant 
use of standard practices. Categories of 
containment are considered separately 
in order that such combinations can be 
conveniently expressed in the NIH 
Guidelines. 
Physical containment conditions 
within laboratories, described in 
Appendix G, may not always be 
appropriate for all organisms because of 
their physical size, the number of 
organisms needed for an experiment, or 
the particular growth requirements of 
the organism. Likewise, biological 
containment for microorganisms 
described in Appendix I may not be 
appropriate for all organisms, 
particularly higher eukaryotic 
organisms. However, significant 
information exists about the design of 
research facilities and experimental 
procedures that are applicable to 
organisms containing recombinant DNA 
that is either integrated into the genome 
or into microorganisms associated with 
the higher organism as a symbiont, 
pathogen, or other relationship. This 
information describes facilities for 
physical containment of organisms used 
in non-traditional laboratory settings 
and special practices for limiting or 
excluding the unwanted establishment, 
transfer of genetic information, and 
dissemination of organisms beyond the 
intended location, based on both 
physical and biological containment 
principles. Research conducted in 
accordance with these conditions 
effectively confines the organism. 
For research involving plants, four 
biosafety levels (BLl-P through BL4-P) 
are described in Appendix P. BLl-P is 
designed to provide a moderate level of 
containment for experiments for which 
there is convincing biological evidence 
that precludes the possibility of 
survival, transfer, or dissemination of 
recombinant DNA into the environment, 
or in which there is no recognizable and 
predictable risk to the environment in 
the event of accidental release. BL2-P is 
designed to provide a greater level of 
containment for experiments involving 
plants and certain associated organisms 
in which there is a recognized 
possibility of survival, transmission, or 
dissemination of recombinant DNA 
containing organisms, but the 
consequence of such an inadvertent 
release has a predictably minimal 
biological impact. BL3-P and BL4-P 
describe additional containment 
conditions for research with plants and 
certain pathogens and other organisms 
that require special containment 
because of their recognized potential for 
significant detrimental impact on 
managed or natural ecosystems. BLl-P 
relies upon accepted scientific practices 
for conducting research in most 
ordinary greenhouse or growth chamber 
facilities and incorporates accepted 
procedures for good pest control and 
cultural practices. BLl-P facilities and 
procedures provide a modified and 
protected environment for the 
propagation of plants and 
microorganisms associated with the 
plants and a degree of containment that 
adequately controls the potential for 
release of biologically viable plants, 
plant parts, and microorganisms 
associated with them. BL2-P and BL3- 
P rely upon accepted scientific practices 
for conducting research in greenhouses 
with organisms infecting or infesting 
plants in a manner that minimizes or 
prevents inadvertent contamination of 
plants within or surrounding the 
greenhouse. BL4-P describes facilities 
and practices known to provide 
containment of certain exotic plant 
pathogens. 
For research involving animals, which 
are of a size or have growth 
requirements that preclude the use of 
conventional primary containment 
systems used for small laboratory 
animals, four biosafety levels (BLl-N 
through BL4-N) are described in 
Appendix Q. BLl-N describes 
containment for animals that have been 
modified by stable introduction of 
recombinant DNA, or DNA derived 
therefrom, into the germ-line (transgenic 
animals) and experiments involving 
viable recombinant DNA-modified 
microorgcuiisms and is designed to 
eliminate the possibility of sexual 
transmission of the modified genome or 
transmission of recombinant DNA- 
derived viruses known to be transmitted 
from animal parent to offspring only by 
sexual reproduction. Procedures, 
practices, and facilities follow classical 
methods of avoiding genetic exchange 
between animals. BL2— N describes 
containment w'hich is used for 
transgenic animals associated with 
recombinant DNA-derived organisms 
and is designed to eliminate the 
possibility of vertical or horizontal 
transmission. Procedures, practices, and 
facilities follow classical methods of 
avoiding genetic exchange between 
animals or controlUng arthropod 
transmission. BL3— N and BL4— N 
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