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Thermocouple fluctuation acceptance criteria


I wanted to know if there was an industry standard for what are acceptable fluctuations in temperature from the setpoint of one thermocouple and betweeen all thermocouples in the same autoclave chamber. I usually come across +/- 1C for one location and +/- 2C between locations. I’m using Type T TCs and currently experiencing fluctuations of 1-2C in the same location and 1-2.5C between all locations. Either my acceptance criteria is not correct or there is a reason for getting high fluctuations.The TCs are placed in agar which might account for the fluctuations?

According to EN285 (HTM 2010):

the temperature measured in each load item does not fluctuate
more than ± 1 º C, and does not differ from that in other load items
by more than 2 º C;

Thanks for the reply. Would these criteria also be true for discard cycles and cycles that were used to process growth media for internal use only, for example - so not a medical device or has no use in healthcare? Is it not important to just be within the sterilisation band e.g. 121-124C rather than fail a cycle because of fluctuations which are within the band?