Explanation of terms for biological indicators

D-value/decimal reduction time:
Quantity used to describe the resistance of microoranisms. Corresponds to the time in minutes required under certain conditions to reduce the bacterial count to one tenth of the initial value.

Resistance of an organism to external agents. In a given environment, the D value provides a measure of the resistance of comparable organisms. 

Rogue BIs
Late survivors
Anomalous BIs
Individual biological indicators from a lot that show unexpectedly high resistance and, contrary to expectations, survive a given decontamination process.