Although the formula for determining an F0 value is quite scientific, the logic behind it can be compared to an ordinary task that we can all relate to. When baking brownies, the box says to bake them at 350 °F for 35 minutes. However, because we are sometimes impatient, the batter is put in when the oven is only preheated to 200 °F. So, what happens while the oven continues to ramp up the temperature to reach 350 °F? Of course, the brownies do not wait, and the batter partially cooks during this time, which impacts the overall duration required and results in potentially undercooked or overcooked brownies.
A similar logic applies to using an autoclave for sterilizing medical equipment. There are certain time and temperature thresholds that must be met in order to kill harmful organisms and achieve safe sterilization. Sterilizing at a lower temperature increases the amount of time required, whereas the higher temperatures will achieve sterilization much faster. The calculation for F0 in a particular application is the formula used to ensure efficient and effective sterilization is achieved.
There are many factors that are considered such as cycle speed, efficiency, and product exposure to find the right balance for managing sterilization cycles. Over sterilizing, at high temperatures for too long, can be costly or potentially begin to cause degradation to the devices being sterilized. Underexposure or temperatures that are too low will not provide adequate sterilization. Depending upon the product being sterilized, there is often an industry standard to ensure the depletion of all potentially harmful bacteria and a baseline that is used in determining the F0 value.
Just as the brownies are partially cooked before reaching 350 °F, some bacteria will be killed before the autoclave reaches 121 °C. To take this into account, the F0 calculation is used to show the equivalent of heating something at a lower temperature. For instance, let’s use an example product that must be held at 121 °C for 12 minutes to achieve sterility. If the autoclave was only heated to 100 °C, it would take longer than 12 minutes to reach the proper sterility. The F0 calculation tells users this value, so the cycle is not extended beyond what is necessary, saving both time and energy.
With the MadgeTech Data Logger Software, a number of sterilization units can easily be applied and displayed in reports. This gives users the ability to see the process of sterilization that occurred during the entire cycle, including during the ramp-up time. To learn more about this feature of the software, contact our Technical Sales team today.