In this article, we take a look at Systec Autoclaves and see how they are designed to be as energy efficient as possible to pass the benefits on to the user.
Round vs. Rectangular Chambers
To ensure a 100% steam atmosphere necessary for accurate sterilisation, Systec utilise round chamber autoclaves which eliminate the possibility of air pockets, compared with traditional rectangular autoclaves. A circular chamber is also stronger than a rectangular chamber and ensures a consistent temperature and pressure throughout the chamber, which provides reproducible cycles. A stronger chamber is ideal for a faster and more efficient thermal transfer as it reduces cycle times.
Rectangular autoclave vessel walls require a greater amount of energy to heat and a greater amount of time to cool the contents being autoclaved after sterilisation due to their thickness, compared with a circular vessel. A Systec 430L autoclave will use an 18kW steam generator, compared with a rectangular autoclave with a volume of 250L which uses a 65kW steam generator.
Rectangular vessel autoclaves are much heavier and often require structural reinforcement. By way of comparison, the weight of a Systec 430L autoclave is less than half the weight of a competitor’s 250L autoclave.
Systec Autoclaves Create a 100% Steam Environment for Effective Sterilisation
To achieve effective sterilisation, air must be removed to ensure there is a 100% steam atmosphere inside the chamber. Traditional autoclaves exhaust air from the top of the chamber, whilst introducing steam into the bottom. As air is heavier than steam, it sinks to the bottom whilst steam rises to the top. This often leaves air pockets forming at the bottom of the chamber below the steam. Unless the items being autoclaved are in contact with 100% steam, effective sterilisation will not occur. Systec autoclaves, on the other hand, have been designed to exhaust air from the bottom of the chamber whilst introducing steam at the top. The steam then forces the air to the bottom and ensures that no air pockets exist, ensuring a 100% steam environment within the chamber.
There are many ways for autoclaves to create steam to introduce into the sterilisation chamber with some being more efficient than others. Most facilities have a steam line incorporated into the lab which connects to the autoclave. However, the reliability of the steam line will determine the reliability of the autoclave. This can also make installation time-consuming and costly. An alternative method is to have an external steam generator provide steam to the autoclave. However, this method takes up additional lab space and the cost of a steam generator must be added to the total cost of the autoclave. Some autoclaves produce their own steam by heating a reservoir of DI water within the sterilisation chamber using heating elements. While this method is effective, it is also time-consuming.
All Systec autoclaves have an innovative steam generator located inside the housing of the system that maintains steam under pressure, making it immediately available and allows for fast heat-up times. It is also worthwhile to note that none of the heating elements are in contact with the chamber which would lengthen cooling times.
With a Systec autoclave, after a cycle is complete, the steam will simply condense to water and drain from the system. This method prevents excess humidity and odours and protects waste water pipes from extreme temperature damage that would be caused by steam.
Superior Quick-Cooling Methods for Liquid Sterilisation
Conventional cooling methods, such as releasing pressure and venting steam, are sufficient when autoclaving waste or instruments. However, liquids need to be cooled while under pressure to prevent boil over. Systec autoclaves utilise an exclusive Radial Ventilation component which consists of a fan, located in the lid of the autoclave, that runs at the end of the sterilisation cycle. This fan will start the cooling process by increasing air circulation through the chamber. As the radial ventilator does not reach into the chamber, the loading capacity is not compromised for cooling. In order to help vent the chamber after each cycle, Systec autoclaves have a fully automated lid which will open automatically after the chamber reaches a safe temperature. As a safety feature, the door can only be opened when the autoclave contents have cooled to 80C.
Correct Door Sealing
Many traditional autoclaves have a manually operated lid that consists of tightening one or more screws. This method can result in an uneven seal which can lead to leaks, comprising the sterilisation process. To prevent leakage, Systec autoclaves have an automated lid which ensures optimal sealing each time. Upon closing, the lid is automatically locked by a circumferential ring system. A special heat-resistant silicone lip seal becomes tighter as the steam pressure increases.
Are Your Liquids Reaching Sterilisation Temperature or Just Your Autoclave Chamber?
Laboratory autoclaves need to be capable of running a variety of different sterilisation cycles for liquids, instruments and waste. As sterilising liquids is not the same as sterilising instruments and waste, autoclaves should have specifically designed sterilisation programs for each of these applications.
For sterilising liquids, autoclaves must reach a certain temperature that corresponds to the steam inside the chamber, for a certain length of time. Whilst traditional autoclaves will go through this process without ever measuring the temperature of the liquid inside the chamber, Systec autoclaves utilise a temperature probe to ensure liquids reach accurate sterilisation temperatures. The probe extends down into the sterilisation chamber and measures the temperature in a reference vessel (usually a flask). The autoclave’s temperature and run time are then based on this temperature, not that of the sterilisation chamber.
For more information about Systec Autoclaves and the range we stock, click here