sign, and use of gowns, coats, and uni- 
forms. It limits entry into a laboratory 
to those who have been specifically in- 
formed advised of the nature of the re- 
search being conducted. 
In response to a witness who averred 
that PI actually represents no con- 
tainment, it can be noted that PI is 
the equivalent of the physical-contain- 
ment level used in medical microbiolo- 
gical and hospital diagnostic laborato- 
ries throughout the world for han- 
dling infectious organisms. Indeed, it 
was suggested that a need exists for an 
even lower level of physical contain- 
ment than PI (for organisms consid- 
ered of minimal risk). I do not believe 
it prudent, however, to permit a lower 
level of containment for experiments 
covered by the Guidelines. 
In the Decision of the Director pub- 
lished with the NIH-proposed revised 
Guidelines on July 28, 1978, I indicat- 
ed that mouth-pipettjng would no 
longer be permitted in PI contain- 
ment. Since it is already prohibited in 
P2 through P4 containment, this 
would ban the use of mouth-pipetting 
for any experiment covered by the 
Guidelines. One commentor feels that 
mouth-pipetting should not be prohib- 
ited under P2 conditions and should 
definitely be allowed under PI con- 
tainment because of its superior effi- 
ciency. The banning of mouth-pipet- 
ting at the PI level, however is in 
accord with the advice of safety ex- 
perts; the present availability of excel- 
lent mechanical devices for pipetting 
makes the alternative, in my opinion, 
a practicable one. 
A correspondent suggested that use 
of biohazard signs at the P2 level of 
containment should be discontinued: 
“They should be reserved for demon- 
strated biological hazards. There is a 
real danger that overuse of these signs 
in cases where workers know they do 
not apply will lead to the ignoring of 
all biohazard signs.” While I recognize 
the concern expressed, I feel it pru- 
dent to require the universal sign at 
the P2 level when recombinant DNA 
materials are being handled. 
For the P3 level of containment, one 
commentator suggested that an auto- 
clave be within the controlled labora- 
tory area, if not the laboratory itself, 
rather than merely in the same build- 
ing. Another commentator makes a 
similar point for the P2 level. This 
issue was raised in comments on the 
revision of the Guidelines proposed by 
the Recombinant DNA Advisory Com- 
mittee (PRG-RAC, Federal Register, 
September 27, 1977). As stated in my 
Decision (Federal Register, July 28, 
1978), “* * * an absolute requirement 
that the autoclave must be within the 
controlled area is nbt considered ap- 
propriate, since contaminated material 
can be safely transported. Such a re- 
quirement would exclude the use of 
FEDERAL 
NOTICES 
autoclaves in waste-staging areas that 
have been conveniently sited to sup- 
port an entire facility.” 
A commentor questions for entrance 
of children into P3 facilities. After 
considering this issue, I have decided 
to (1) retain the stipulation that per- 
sons under 18 years of age shall not 
enter a P4 facility, (2) raise the age 
limit for entry to P3 laboratories from 
12 to 16 years of age, and (3) eliminate 
the age stipulation for P2 laboratories. 
A recommendation that. the use of a 
separate centrifuge room or cubicle be 
provided in a P3 facility to contain 
spills occasioned by rotor failure has 
not been accepted. All rooms in the P3 
facility must be capable of being 
sealed to facilitate space decontamina- 
tion. Modem centrifuges do not pre- 
sent the potential hazard associated 
with earlier models. Rotor design, op- 
eration requirements, the design integ- 
rity of the centrifuge well, and the 
availability of sealed centrifuge cups 
adequately control the aerosol hazard 
associated with centrifuging. 
Other concerns relating to the P3 
level of physical containment have 
been considered: 
• Section II-B-3-c-(7), dealing with 
ventilation, has been completely re- 
written to clarify the intent to permit 
recirculation of HEPA-filtered ex- 
haust air. 
• Section II-B-3-c-(5), which re- 
quires that laboratory doors be self- 
closing, has been deleted. As a corre- 
spondent observes, the Guidelines 
should be worded in such a way as to 
make facility design compatible with 
Section II-B-3-a-(l) requiring labora- 
tory doors to be closed while experi- 
ments are in progress has been re- 
tained. 
• A recommendation that the 
Guidelines be revised to require that 
booties be worn at all times within the 
P3 laboratories has not been accepted. 
For the P4 level of physical contain- 
ment, one correspondent would have 
the Guidelines specifically require the 
use of gloves. In response, it can be 
noted that most P4 experiments use 
Class III cabinets, which are fitted 
with attached arm-length rubber 
gloves. As shown in Table II of the 
PRG-NIH, however, one can work in 
open-faced biological safety cabinets 
with augmented biological contain- 
ment. In this case, the requirement for 
gloves has now been explicitly set 
forth by addition of text to Table II. 
In response to commentors’ sugges- 
tions and NIH review, other changes 
have been made in the Guidelines. For 
example: 
• Sections II-B-l-a-(5), II-B-2-a- 
(5), and II-B-3-a-<5) have been 
changed to indicate that eating, drink- 
ing, smoking, and storage of foods are 
not permitted in the “laboratory area 
REGISTER, VOL 43, NO. 247— FRIDAY, DECEMBER 
[ 8 ] 
60085 
in which recombinant DNA materials 
are handled.” 
• Sections II-B-2-a-(10) and II-B-3- 
a-(ll) have been changed to mandate 
the posting of the universal biohazard 
sign on freezers and refrigerators "or 
other units” used to store organisms 
containing recombinant DNA mole- 
cules. In addition, the requirement for 
identifying storage units within the P4 
facility with the universal biohazard 
sign has been included in Section II- 
B4-a-(15). 
• Additional language to clarify the 
use of the terms “sterilized” and "de- 
contaminated” has been added to Sec- 
tions II-B-l-a-(3), II-B-2-a-(3), II-B- 
3-a-(3), II-B-3-a-(8), II-B-4-a-(9), and 
II-B-4-a-(10). 
• The requirement that the labora- 
tory be kept neat and clean has been 
added to PI; it was already present at 
P2, P3, and P4. 
• A new Section II-B-4-G8) has 
been added concerning vacuum outlets 
in the P4 facility. 
SHIPMENT 
New language to clarify the intent of 
Section II-C relating to shipment has 
been suggested by the Department of 
Transportation. This language has 
been incorporated (with minor modifi- 
cations) into the Guidelines. The sug- 
gestion of one correspondent that cer- 
tain clones be exempt from these re- 
quirements has not been accepted. 
BIOLOGICAL CONTAINMENT 
Certification of Host-Vector Systems 
Most comments on the biological 
containment provisions of the pro- 
posed revised Guidelines related to de- 
velopment, review, and approval of 
host-vector (HV) systems other than 
E. coli K-12. In particular, commenta- 
tors from the scientific community 
continue to urge development of such 
alternate systems. Thus, one corre- 
spondent wrote, “The anticipated po- 
tential of recombinant DNA in agricul- 
ture will be difficult, if not impossible, 
to realize with E. coli K-12 host- vector 
systems. Therefore, it is imperative 
that attention be given to the develop- 
ment and approval of alternate HV1 
systems that may be useful in genetic 
engineering of plants and inverte- 
brates.” Another correspondent wrote, 
“While many of the regulations do not 
add to the safety of what are basically 
safe experiments, they do serve to in- 
hibit the development of new and ver- 
satile vector systems * * \ The redun- 
dant safety testing program is too 
onerous, time-consuming, and in our 
opinion, not scientifically justified.” 
While I agree that research based on 
other host-vector systems must pro- 
ceed, I believe that certification of 
these systems should be approached 
conservatively. The new systems raise 
22, 1978 
