Biological indicators incubator GKE, or spore tests, are used to check the validity of the sterilization processes of saturated vapor (class N, S and B cycles) and chemical gas autoclaves.
First of all it is necessary put a vial in autoclave chamber, with instruments, and start the sterilization process. When it ends, activate the vial and incubate it at 57.5°C for 24 hours. At the end of the incubation the test gives the result: if the vial does not change color and remain blue/purple the result is positive, if it changes the color in brown/yellow the result is negative (that means the sterilization process failed).