8 
Dr. McGarrity noted that Appendix G-II-B-3-a-(l ) refers to "...harvesting 
infected tissues from animals or eggs..." while Appendix G-II-C-3-a refers 
to " . . .harvesting of tissues or fluids frcm experimental animals ard 
errbryonate eggs...." The word "infected" is not used in Appendix G-II-C-3-a 
even though Appendix G-II-B specifications refer to the BL2 level of contain- 
ment while Appendix G-II-C specifications refer to the more stringent BL3 
containment level. Dr. Barkley said both Appendix G-II-B-3-a-(l ) ard 
Appendix G-II-C-3-a should contain the word "infected." 
Dr. McGarrity then referred to the language of Appendix G-II-D-2-(l ) which 
requires that? 
"Laboratory animals involved in experiments requiring BL4 level physical 
containment shall be housed either in cages contained in Class III 
cabinets or in partial containment caging systems (such as Horsfall 
units [11])/ open cages placed in ventilated enclosures, or solid-wall 
and -bottom cages placed on holding racks equipped with ultraviolet 
irradiation lamps and reflectors that are located in a specially 
designed area in which all personnel are required to wear one-piece 
positive pressure suits." 
Dr. McGarrity said UV irradiation must be regularly monitored to be efficient 
and asked if Dr. McKinney could offer seme rationale for the recommendation 
for UV irradiation. Dr. McKinney replied that Appendix G-II-D-2-(l ) refers 
to a high containment BL4 facility where critical attention is paid to moni- 
toring. He said a number of studies demonstrate the efficacy of UV lamps 
attached to animal racks for minimizing aerosol exposure within animal 
facilities . 
Dr. Rapp regretted the departure frcm the P designations. He said it is 
easy for ccnmittees to change the Guidelines to the BL designations; but the 
P designations are new part of a tradition and will undoubtedly continue to 
be used. Dr. Barkley agreed that the P designations will probably be refer- 
enced for many years. He thought, however, that commonality of language 
and substance in laboratory biosafety designations is an important goal. 
Dr. Rapp asked if "chewing" is considered to be "eating." He also asked 
if self-closing doors could be spring-loaded or if they had to be electrical. 
Dr. Barkley responded that "chewing" is defined as "eating;" the emphasis 
is on keeping things out of the mouth. Dr. Barkley said the requirement 
for self-closing doors may be met by spring-loaded devices. 
Dr. McKinney referred the RAC to a letter frcm Mr. C. Searle Wadley and 
Dr. John H. Keene of Abbott Laboratories (tab 1171). Dr. McKinney said 
this letter expressed concern that seme language in the Guidelines may be 
confusing and suggested language be added to Section III-D-4 to emphasize 
the need for appropriate containment for exempt experiments. The letter 
suggested exempt experiments "be performed at the appropriate biosafety 
level for the host or recombinant organism (for biosafety levels see 
Biosafety in Microbiological and Biomedical Laboratories ) . " Dr. McKinney 
[ 461 ] 
