In a message dated 1/28/00 7:23:58 AM Central Standard Time,
Olsonl@Centocor.com writes:
<< I'd appreciate your comments on the following assertions:
WFI systems run at > 65 or 70 or 75 (depending on the speaker) are
"sterile". Thus, the system bioburden limit should be zero. Any bioburden
recovered should only be Gram positive environmentals. The WFI spec of </=
10 CFU/100 mL represents the process spec only.
>>
WFI systems typically have very low microbial content because of their
elevated temperature operating conditions. However, they are not sterile.
The bioburden limit needn't be zero, although the vast majority of test
samples are zeros in any well engineering, installed and maintained system.
It is important to note though that many firms sample WFI systems in areas
that do not lend themselves to aseptic sampling. The observation of counts
from samples taken in utility areas for example should surprise no one, since
those are usually uncontrolled areas with no prevision for aseptic sampling.
Jim Akers
akainckc@aol.com
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