59400 
Federal Register / Vol. 46, No. 233 / Friday. December 4, 1981 / Notices 
I-E. Exemptions. It must be 
emphasized that the following 
exemptions (4) are not meant to apply to 
experiments described in the Sections I- 
D-1 to I-D-5 as being prohibited. In 
addition, any recombinant DNA 
molecules involving DNA from Class 3 
organisms (1| or cells known to be 
infected with these agents, or any 
recombinant DNA molecules which 
increase the virulence and host-range of 
a plant pathogen beyond that which 
occurs by natural genetic exchange, are 
not exempt unless specifically so 
designated by NIH under Section I-E-5. 
Also. Appendix C overrides the 
exemptions for specified experiments 
involving genes coding for toxins. 
The following recombinant DNA 
molecules are exempt from these 
Guidelines, and no registration with NIH 
is necessary- 
I-E-1. Those that are not in organisms 
or viruses. (5) 
i-E-2. Those that consist entirely of 
DNA segments from a single 
nonchromosomal or viral DNA source, 
though one or more of the segments may 
be a synthetic equivalent. 
Those that consist entirely of 
DNA from a prokaryotic host, including 
its indigenous plasmids or viruses, when 
propagated only in that host (or a 
closely related strain of the same 
species) or when transferred to another 
host by well established physiological 
meaiu; also those that consist entirely of 
DNA from a eukaryotic host, including 
its chloroplasts. mitochondria, or 
plasmids (but excluding viruses), when 
propagated only in that host (or a 
closely related strain of the same 
species). 
l-E-4. Certain specified recombinant 
DNA molecules that consist entirely of 
DNA segments from different species 
that exchange DNA by known 
physiological processes, though one or 
more of the segments may be a synthetic 
equivalent. A list of such exchanges will 
be prepared and periodically revised by 
the Director. NIH. with advice of the 
RAC. after appropriate notice and 
opportunity for public comment. (See 
Section IV-E-l-b-(lHd).) Certain 
classes are exempt as of publication of 
these Revised Guidelines. The list is in 
Appendix A. An updated list may be 
obtained from the Office of 
Recombinant DNA Activities. National 
Institutes of Health, Bethesda. Maryland 
20205. 
l-E-5. Other classes of recombinant 
DNA molecules, if the Director, NIH, 
with advice of the RAC. after 
appropriate notice and opportunity for 
public comment, finds that they do not 
present a significant risk to health or the 
environment. (See Section IV-E-l-b- 
(iHd).) Certain classes are exempt as of 
publication of these Revised Guidelines. 
The list is in Appendix C. An updated 
list may be obtained from the Office of 
Recombinant DNA Activities, National 
Institutes of Health, Bethesda, 
Maryland. 20205. 
I-F. General Definitions. See Section 
rv-c. 
II. Containment 
Effective biological safety programs 
have been operative in a variety of 
laboratories for many years. 
Considerable information, therefore, 
already exists for the design of physical 
containment facilities and the selection 
of laboratory procedures applicable to 
organisms carrying recombinant DNAs. 
[&-19] The existing programs rely upon 
mechanisms that, for convenience, 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 which are applied in 
varying degrees according to the 
estimated biohazard. 
Experiments on recombinant DNAs. 
by their very nature, lend themselves to 
a third containment mechanism — 
namely, the application of highly 
specific biological barriers. In fact, 
natural barriers do exist which 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. The vectors 
that provide the means for replication of 
the recombinant DNAs and/or the host 
cells in which they replicate can be 
genetically designed to decrease by 
many orders of magnitude the 
probability of dissemination of 
recombinant DNAs outside the 
laboratory. 
As these three means of containment 
are complementary, different levels of 
containment appropriate for 
experiments with different recombinants 
can be established by applying various 
combinations of the physical and 
biological barriers along with a constant 
use of the standard practices. We 
consider these categories of 
containment separately here in order 
that such combinations can be 
conveniently expressed in the 
Guidelines. 
In constructing these Guidelines, it 
was necessary to define boundary 
conditions for the different levels of 
physical and biological containment and 
for the classes of experiments to which 
they apply. We recognize that these 
definitions do not take into account all 
existing and anticipated information on 
special procedures that will allow 
particular experiments to be carried out 
under different conditions that indicated 
here without affecting risk. Indeed, we 
urge that individual investigators device 
simple and more effective containment 
procedures and that investigators and 
institutional biosafety committees 
recommend changes in the Guidelines to 
permit their use. 
II-A. Standard Practices and 
Training. The first principle of 
containment is a strict adherence to 
good microbiological practices. [6-15] 
Consequently, all personnel directly or 
indirectly involved in experiments on 
recombinant DNAs must receive 
adequate instruction, (see Sections IV- 
D-l-g. IV-D-5-d and lV-D-6-b.). This 
shall, as a minimum, include instructions 
in aseptic techniques and in the biology 
of the organisms used in the 
experiments, so that the potential 
biohazards can be understood and 
appreciated. 
Any research group working with 
agents with a known or potential 
biohazard shall have an emergency plan 
which describes the procedures to be 
followed if an accident contaminates 
personnel or the environment. The 
principal investigator must ensure that 
everyone in the laboratory is familiar 
with both the potential hazards of the 
work and the emergency plan. (See 
Sections IV-D-5-e and IV-D-3^.) If a 
research group is working with a known 
pathogen where there is an effective 
vaccine it should be made available to 
all workers. Where serological 
monitoring is clearly appropriate it shall 
be provided. (See Sections IV-D-l-h 
and IV-D-6-C.) 
11-B. Physical Containment Levels. 
The objective of physical containment is 
to confine organisms containing 
recombinant DNA molecules, and thus 
to reduce the potential for exposure of 
the laboratory worker, persons outside 
of the laboratory, and the environment 
to organisms containing recombinant 
DNA 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 hazards are performed. 
Combinations of laboratory practices, 
containment equipment, and special 
laboratory design can be made to 
[ 289 ] 
