Calculations in Sterilisation Flashcards
1
Q
what does a higher D value indicate
A
more resistant bacterium
2
Q
what is the D value
A
time required to calculate 90% of organisms
3
Q
what is the Z value
A
temperature increase that reduces D value by 90%
temperature increase that will result in the bacteria being killed 10 times faster
4
Q
what is the F value
A
expresses lethality of heat treatment t any temperature equivalent to treatment at a reference temperature
it depends on resistance of reference organism, expressed in minutes
mainly used in moist heat sterilisation and only if temp is the sole factor influencing the process
