The operation of autoclaves can be broken down into three categories: those that use gravity, those that use vacuum-induced sterilization, and those that use pre-vacuum sterilization. However, there are some autoclaves that employ both approaches to the sterilization process. Both varieties of autoclaves utilize high-temperature steam as their sterilization method. Additionally, the chamber is pressurized, which prevents the release of any air within the chamber and enables the heat to more thoroughly permeate the substance being sterilized. There are differences between the mechanisms, and this article will explain how the two distinct kinds of systems work with the various media that are associated with each type respectively.

Autoclaves That Use Gravity
Gravity autoclaving, also referred to as gravity displacement autoclaving, is the most fundamental form of autoclaving, and it is appropriate for sterilizing the most frequently used laboratory media. This includes biohazardous waste as well as glassware and stainless steel utensils. In order to autoclave using gravity as a driving force, steam must be pumped into the autoclave chamber. Which then displaces the surrounding air and compels it to escape through the exhaust valves, allowing the remaining steam to sanitize whatever is inside. This mechanism is helpful because it has a simple design and does not depend on any other mechanisms that are peripheral to it in order to replace the surrounding air with steam. improving both the cost-effectiveness and dependability of autoclaves of this type.

Because the majority of the media or items that need to be sterilized are straightforward in their construction and do not have any openings or obstacles that the steam could potentially run into, the steam displacement function is all that is required for adequate sterilization. Because of these factors, gravity autoclaves are the most common type of  high pressure autoclave available for purchase, and they are also the type of  high pressure autoclave that is typically recommended for the majority of applications.

Vacuum Autoclaves
When it comes to sterilization, vacuum autoclaving, which is also known as pre-vacuum autoclaving or simply sterilizing, is the method of choice for situations in which air cannot be easily removed from the medium being sterilized. Items that are large or porous, such as animal cages and bedding sterilization, as well as wrapped surgical kits, may fall under this category. Because it completely evacuates the ambient air within, the vacuum function in these autoclaves enables a more thorough sterilization of the contents. This makes it possible for high-temperature steam to penetrate and sterilize areas that are normally occupied by ambient air. Additionally, the vacuum function in these autoclaves can be more effective at sterilizing certain items that contain difficult-to-reach areas within.

Autoclave Media and the Type of Autoclave That Should Be Used
As was just mentioned, your choice of an  autoclave supplier system is heavily influenced by the autoclave supplier media, otherwise known as the items that require sterilization. In general, steam sterilization is extremely dependable, efficient, quick, and non-toxic. Furthermore, it provides a cost-effective method for rapidly heating and penetrating the chamber's contents, including liquids that have been properly contained. However, this method is not capable of sterilizing powders or oils, and it can only be used on items that are resistant to heat and moisture. Keeping this information in mind, I will now provide a synopsis of the primary media that are utilized by gravity and vacuum-autoclave types.

When it comes to the sanitization of non-porous items, such as those with a hard surface, gravity autoclaves are the way to go:

Polypropylene Pyrex® or Type I borosilicate glassware is recommended for use with most metals, particularly stainless steel surgical instruments and laboratory utensils.

Biological waste

Unwrapped merchandise

The use of vacuum, both before and after the sterilization process, is recommended for the following types of items:

In preparation for a steam autoclave cycle, media solutions are placed in containers such as tissue culture flasks with loose caps.

Pipette tips and other products made of high-density polyethylene, like syringes, are examples.

Items that are dry and can be wrapped and used to trap air Animal pens and bedding

Picking the Right Autoclave

In order to select the appropriate autoclave for your needs, you need to evaluate not only the kind of medium that will be autoclaved but also its throughput capacity, the amount of lab space that is at your disposal, and your access to various utilities, such as electricity (with the appropriate power output), water, and house steam.

There is great flexibility in the design of gravity autoclaves, including front- and top-loading types, due to the simplicity of the gravity-displacement mechanism, which requires an autoclaving chamber, a heating mechanism, intake and exhaust valves. This is because the gravity-displacement mechanism only requires these four components.

The top-loading type of  is beneficial because it enables maximum loading space, requires only a minimal amount of floor space, and does not require any building steam connection. This is because the vertical chamber design enables water to rest at the bottom, where it is then converted into steam by a heating element located at the bottom of the chamber. Take note that many of the autoclaves currently available on the market, particularly compact top-loading autoclaves, typically require nothing more than access to the appropriate type of electrical outlet and sufficient space to set up the autoclave.

When used in geographical areas with high humidity or at higher altitudes, gravity autoclaves are also particularly helpful and can be of great benefit. Because they are able to reliably maintain the relationship between pressure and temperature within the autoclave chamber and overcome differences in boiling points at higher altitudes by adjusting the position of the exhaust valve, opening and closing it as necessary. Their functions, which are referred to as high altitude autoclaves, make it possible for proper sterilization to take place in hospitals and laboratories located in regions with high altitude terrains.

When it comes to the size of your autoclave, it is important to buy the appropriate size autoclave that will accommodate the equipment that needs sterilizing without going overcapacity. This is especially important for smaller labs, where it is especially important to limit energy use and costs. For this purpose, several autoclaves are available in capacities ranging from 50 L to 70 L. These autoclaves offer an excellent compromise between relatively high capacity and low energy consumption.