Bioequivalence and Bioavailability Forum

Hi sree1805,

❝ in case of the deep freezers (-20 degree celsius) some of them use the freeze -20 plus or minus 10 and some of them use plus or minus 8 and some in plus or minus 5.

Amazing what »some of them« do. Are you talking about household-freezers? Lab-freezers generally maintain the temperature at -20 °C to ±1 °…

❝ I want to know on what basis the plus or minus 5/8/10 is decided to run the freezers.

I guess you don’t want samples to thaw? Following table gives the cumulative time during one year to expect the temperature to be ≥ 0 °C:

 x   SD   time     
───────────────────
-20  10   8 days   
-20   8  54 hours  
-20   5  17 minutes

I hope »they« have both an alarm system and a quick chain of responses in place.