SCHERING CORPORATION 
BLOOMFIELD, N. J. 07003 
TELEPHONE: (201)429-4000 
TELEX: 138183 
CABI ES: SCHERING BLOOMFIELD. N.J. 
May 21, 1984 
Dr. William J. Gartland, Jr. 
Director, Office of Recombinant DNA Activities 
Building 31, Room 3B10 
National Institutes of Health 
Bethesda, Maryland 20205 
Dear Dr. Gartland: 
Schering Corporation has reviewed the Federal Register announcment (49 FR 
17672) regarding items to be considered at the upcoming RAC meeting on June 1, 
1984. The following comments are for Item 1: Proposed Amendment of 
Procedures for Scale-Up of Organisms Listed in Appendix C . (49 FR 17672-17673) . 
Item 1-1 Substitution of the word "minimize" for "prevent" in Appendix K-II-D. 
HEPA filters are only 99.97% efficient for particles of 0.3u diameter, so 
to say that HEPA filtration "prevents" release of recombinant organisms is 
incorrect. Use of the word "minimize" would more accurately reflect the 
removal properties of a HEPA filter. If this is the intent of the proposed 
change, we support it. 
Item 1-3 
The large scale recommendations in Appendix K represent an adequate and 
reasonable approach to the problem of containing large volumes of recombinant 
organisms. As currently written, the Pl-LS recommendations provide for 
flexibility in approach while assuring the safety of workers and the community 
and environmental protection. Addition of a statement to Appendix C-II, C-III 
and C-IV permitting "some latitude in the application of Pl-LS requirements" 
would empower the IBC to create a PO-LS class of requirements. The Pl-LS 
recommendations should be the minimum requirements for handling large volumes 
of recombinant organisms. While we agree that the IBCs should have the 
flexibility necessary to carry out their responsibilities, we are opposed to 
the IBC having so much flexibility that the Guidelines could be ignored 
compl etely. 
Accordingly, we urge the RAC to reject this proposed change. This 
includes rejection of the change proposed in Item 1-2, since the current 
wording in Appendix C-II, C-III and C-IV is adequate. 
60 ORANCE STREET 
[6761 
