Soil Microorganisms article S7a
Figure 7: Stovetop pressure cooker used for sterilizing agar and other instruments. A trivet was placed into the pressure cooker and 2 to 3 cm of water was added to the bottom of the pot (so that it didn’t touch the bottom of the jars). Jars covered with foil were placed in the center, leaving at least 2 cm between the tops of the jars and the lid of the pressure cooker.