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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Bacteria used to check the working efficiency of an autoclave is:
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The correct answer is  There are three indicators that may be used to detect the efficacy of the autoclave process: 

Physical: Pressure and temperature recording devices.
Chemical: Indicators that change color after being exposed to specific temperatures, such as temperature-sensitive tape. The color change upon exposure to the given temperature.
Biological: Bacillus stearothermophilus spores are used, due to its resistance to heat, for the testing that measures the biological performance of the autoclave process.