NOTICES 
33071 
be divided into two categories: (i) a set 
of standard practices that are general- 
ly used in microbiological laboratories, 
and Cii> special procedures, equipment, 
and laboratory installations that pro- 
vide physical barriers which are ap- 
plied in varying degrees according to 
the estimated biohazard. 
Experiments on recombinant DNA's, 
by their very nature, lend themselves 
to a third containment mechanism— 
namely, the application of highly spe- 
cific biological barriers. In fact, natu- 
ral barriers do exist which limit either 
(i) the infectivity of a vector, or vehi- 
cle. (plasmid, bacteriophage, or virus) 
to specific hosts or (ii) its dissemina- 
tion and survival in the environment. 
The vectors that provide the means 
for replication of the recombinant 
DNA's and or the host cells in which 
they replicate can be genetically de- 
signed to decrease by many orders of 
magnitude the probability of dissemi- 
nation of recombinant DNA's outside 
the laboratory. 
As these three means of contain- 
ment are complimentary, different 
levels of containment appropriate for 
experiments with different recombin- 
ants 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 con- 
tainment separately here in order that 
such combinations can be conveniently 
expressed in the guidelines. 
In constructing these guidelines, it 
was necessary to define boundary con- 
ditions for the different levels of phys- 
ical and biological containment and 
for the classes of experiments to 
which they apply. We recognize that 
these definitions do not take into ac- 
count all existing and anticipated in- 
formation on special procedures that 
will allow particular experiments to be 
carried out under different conditions 
than indicated here without affecting 
risk. Indeed, we urge that individual 
investigators devise 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 Train- 
ing. The first principle of containment 
is a strict adherence to good microbio- 
logical practices. (6-15) Consequently, 
all personnel directly or indirectly in- 
volved in experiments on recombinant 
DNA's must receive adequate instruc- 
tion. This should as a minimum in- 
clude instruction in aseptic techniques 
and in the biology of the organisms 
used in the experiments, so that the 
potential biohazards can be under- 
stood and appreciated. 
Any research group working with 
agents with a known or potential bio- 
hazard should have an emergency 
plan which describes the procedures to 
be followed if an accident contami- 
nates personnel or the environment. 
The principal investigator must insure 
that everyone in the laboratory is fa- 
miliar with both the potential hazards 
of the work and the emergency plan. 
If a research group is working with a 
known pathogen for which an effec- 
tive vaccine is available, all workers 
should be immunized. Serological 
monitoring, where appropriate, should 
be provided. 
II-B. Physical Containment Levels. 
The objective of physical containment 
is to confine organisms containing 
novel 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 contain- 
ing novel recombinant DNA molecules. 
Physical containment is achieved 
through the use of laboratory prac- 
tices. containment equipment, and spe- 
cial 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 protec- 
tion 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. 
Combinations of laboratory prac- 
tices. containment equipment, and spe- 
cial laboratory design can be made to 
achieve different levels of physical 
containment. Four levels of physical 
containment, which are designated as 
PI. P2, P3. and F4, are described. It 
should be emphasized that the de- 
scriptions and assignments of physical 
containment detailed below are based 
on existing appproaches. to contain- 
ment of pathogenic organisms. For ex- 
ample, the "Classification of Etiologic 
Agents on the Basis of Hazard." (7) 
prepared by the Center for Disease 
Control, describes four general levels 
which roughly correspond to our de- 
scriptions for PI. P2. P3. and P4; and 
the National Cancer Institute de- 
scribes three levels for research on on- 
cogenic viruses which roughly corre- 
spond to our P2, P3. and P4 levels. (8) 
It is recognized that several differ- 
ent combinations of laboratory prac- 
tices, containment equipment, and spe- 
cial laboratory design may be appro- 
priate for containment of specific re- 
search activities. The guidelines, 
therefore, allow alternative selections 
of primary containment equipment 
within facilities that have been de- 
signed to provide P3 and P4 levels of 
physical containment. The selection of 
alternative methods of primary con- 
tainment is dependent, however, on 
the level of biological containment 
provided by the host-vector system 
used in the experiment. Consideration 
will also be given by the Recombinant 
DNA Advisory Committee to other 
combinations which achieve an equiva- 
lent level of containment. Additional 
material on physical containment for 
plant host-vector systems is found in 
sections III-C-3 and III-C-4. 
II-B-1. PI Level 
II-B-l-a. Laboratory Practices. 
II-B-l-a-(l). Laboratory doors shall 
be kept closed while experiments are 
in progress. 
II-B-l-a-(2). Work surfaces shall be 
docontaminated daily, and immediate- 
ly following spills of organisms con- 
taining recombinant DNA molecules. 
II-B-l-a-(3). All biological wastes 
shall be decontaminated before dispos- 
al. Other contaminated materials such 
as glassware, animal cages, and labora- 
tory equipment shall be decontaminat- 
ed before washing, reuse, or disposal. 
II-B-l-a-(4). Mechanical pipetting 
devices shall be used: pipetting by 
mouth is prohibited. 
II-B-l-a-(5). Eating, drinking, smok- 
ing. and storage of foods are not per- 
mitted in the working area. 
II-B-l-a-(6). Persons shall wash 
their hands after handling organisms 
containing recombinant DNA mole- 
cules and when they leave the labora- 
tory. 
II-B-l-a-(7). Care shall be taken in 
the conduct of all procedures to mini- 
mize the creation of aerosols. 
II-B-l-a-(8). Contaminated materi- 
als that are to be decontaminated at a 
site away from the laboratory shall be 
placed in a durable leak-proof contain- 
er which is closed before removal from 
the laboratory. 
II-B-l-a-(9). An insect and rodent 
control program shall be instituted. 
II-B-l-a-(lO). The use of laboratory 
gowns, coats, or uniforms is discretion- 
ary with the laboratory supervisor. 
II-B-l-a-(ll). Use of the hypoder- 
mic needle and syringe shall be avoid- 
ed when alternative methods are avail- 
able. 
II-B-l-b. Containment Equipment 
Special containment equipment is not 
required at the PI level. 
II-B-l-c. Special Laboratory Design. 
Special laboratory design is not re- 
quired at the PI level. 
II-B-2. P2 Level 
II-B-2-a. Laboratory Practices. 
II-B-2-a-(l). Laboratory doors shall 
be kept closed while experiments are 
in progress. 
II-B-2-a-(2). Work surfaces shall be 
decontaminated daily, and immediate- 
ly following spills of organisms con- 
taining recombinant DNA molecules. 
II-B-2-a-(3). All biological wastes 
shall be decontaminated before dispos- 
al. Other contaminated materials such 
as glassware, animal cages, and labora- 
FEDERA1 REGISTER, VOL 43, NO. 146 — FRIDAY, JULY 28, 1978 
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