5 
and methods used in the testing shall be appropriate for the equipment 
design and for recovery and demonstration of the test organism. Records 
of tests and results shall be maintained on file." 
Dr. tfest said the suggestion to index allowable pressure to some fraction of 
the system's designed working pressure is appropriate, but questioned how a 
, reasonable value would be determined: He suggested that the Large-Scale \ forking 
Group contact the American Society for Testing and Materials (ASTLJ) and request 
information on vessel and piping failures. 
Mr. Barbeito said that, in his experience, sterilizers and associated piping 
hold up veil under hydrostatic pressures one and one-half times operating pres- 
sure, however, leakage may occur around gasketed joints and doors, etc. Thus, 
the pressure capacity of the ancillary equipment is a very important contain- 
ment consideration. Mr. Barbeito pointed out that at 10 p>sig, mechanical seals 
around the drive shafts leak; even at negative pressures, sealing the shafts 
is a difficult task. Mr. Galliher frcm Biogen, Inc., said that Biogen fer- 
menters are steam sterilized at 15 psig. Mr. Barbeito asked if steam leakage 
occurs around the gaskets during the sterilization cycles. Mr. Galliher said 
that some steam leakage may occur at 15 psig, depending upon how well the equip- 
ment is maintained. He pointed out, however, that at the P3-LS level a steam 
environment is maintained around the rotating seal; this environment would kill 
any escaping organism. Mr. Barbeito questioned whether all organisms would he 
killed as they passed through the steam. He said information on spores and 
viruses suggests they may not be killed on a single passage through steam. 
r 42 i 
