Misinterpretation of Microbiological Data on Gas Plasma Sterilization: Avoiding the Pitfalls.
from: Gas Plasma Sterilization in Microbiology: Theory, Applications, Pitfalls and New Perspectives (Edited by: Hideharu Shintani and Akikazu Sakudo). Caister Academic Press, U.K. (2016) Pages: 141-146.
In this chapter, we discuss avoidance of clumping, tailing phenomena, and methods for attaining a SAL of 10-6 using a biological indicator (BI). As tailing of a survivor curve is often caused by clumping of the BI, appropriate techniques and confidential know-how to avoid such clumping is required. When such a tailing phenomenon is observed, a SAL of 10-6 cannot be attained, and therefore no D value (decimal reduction value) can be determined and the exposure time for a 9 or 12 log reduction remains undefined. The D value must be determined from the straight line of a 9 log or 12 log reduction survivor curve, and there can only be one D value per microorganism; there is never more than one D value per one microorganism read more ...