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Autoclave loads qualification (advice)


I was looking for advice on general qualification on Autoclaves, I have stumbled across a problem where I work and I am currently trying to get advice from some of our experts but do not seem to be getting anywhere.

Basically we are trying to work out a way to validate a maximum load for filters/sterile crosses. I thought (I not an expert to say the least) that if we could validate a maximum load that we could use that as a worst case scenario.

Say we autoclaved 3 10" filters as the worst case would that mean that any filters less than that would be ok say 3 4" filters (less surface area) or would that have to be a different qualified load.

As I said I am not an expert but we have to get some kind of qualification worked out before the 24th December.

any comments and criticism is most welcome.

Typically, a max load is not worst case. It all depends on the thermal properties of the filters. A greater thermal mass (not SA) typically takes longer to attain temperature thereby elongating the cycle, thus higher lethality. A single filter, the worst case one(slowest to heat), in your cold spot is typically the basis for your trials. It still won’t get you out of at least one max load, but you can start there. Don’t forget about the drying aspect of filters, that can be pretty long and tiresome in the development

I’m in the middle of development for filter sterilization in the autoclave.
The process parameters are:
Temperature: 121-124 [oC] (set point 122.5 [oC]).
Vacuum: 3 vacuum cycles.
Drying: 25 minutes (Jacket temp 132 [oC]).
The filters are inside filter housing and wrapped with sterilization bag.
At first I had problem of wet filters and sterilization bags in the end of the cycle. This was because of poor drainage of condensate. The solution was to build stainless steel matrix to support the filters (and housing), and in this way to get better drainage.
The sterilization bag is completely dry but the inner side of the filter has little drops in the end of the cycle.
Do I have to consider this cycle as a failure? (Because wet wet load is considered as unsterile)
What can cause this problem? Does the drying time isn’t sufficient?
Can you advise me from your experience?

Thank you in advance