Why f0 value of load cycle should be more than f0 value of biological indicator .Plz reply.
I think I need more context to answer your question. Are you talking about validation cycles, or routine cycles? What sterilization method/approach are you using as per USP <1229>?
Most overkill cycles are validated using a biological indicator with a high F0 kill value (between 15 to 20) calculated as per ISO 11138. Often it is a G. Stearothermophilus, with a population of 10^5 to 10^6 CFU/BI and a resistance of at least 1.5 min at 121°C.
For bioburden / Biological indicator method; often a commercial BI is selected whose F0 kill value best matches the required cycle F0. BI challenge must represent worse conditions than the ones posed by the native bioburden of the product/meterial.
False positives are a thing, and are somewhat common, so the selection of the biological indicator must be cohreent with the cycle F0 that needs to be demonstrated.
I hope I can be of further assistance
Sir I want to know what is the maximum length acceptable as per regulatory requirements. In a steam Sterlizer/Autoclave.
There is no regulatory requirement on a specific maximum length of a sterilization cycle; but it is required that the manufacturer establishes the maximum (and also the minimum) based on characteristics of the product/mateiral and the knowledge of the bioburden present in them.
You must establish the minimum lethality cycle to validate the worst case for sterility; and your maximum lethality cycle to validate the worst case for stability of the product or its container closure (this one is also supported by stability studies).
I hope this helps.