Generally, gravity cycle, vacuum cycle and liquid cycle are the three most common cycles you will encounter when autoclaving.
Gravity Autoclave Cycle
Gravity autoclaving, also known as gravity displacement autoclaving, is the most basic form of autoclaving.
The process of gravity autoclaving involves removing all ambient air from the steam sterilizer chamber and venting it through the exhaust valve. This is done so that the steam can sterilize the contents of the autoclave.
When the steam is pumped into the autoclave
chamber, it rises to the top because its density is lower than that of air. This forces air to the bottom of the chamber, where it exits the exhaust valve. After the cycle is complete, the steam is released through the blowdown outlet and the cooling process begins.
Autoclaves are commonly used to treat laboratory water, media, regulated medical waste, pharmaceuticals, and non-porous items whose surfaces can come into direct contact with steam.