Shipping Container Validation, Mapping Study Duration, and Where/When to use Mean Kinetic Temperature
I just read the eBook: "Staying Current in Cold Chain Management" and I have a few questions on the validation of shipping, chambers, warehouses.
1) If I need to validate a shipping container, and the size of the container is less than 20m3, how many points do I use and how long is my study? Is the MTK calculation required?
2) If the temperature and relative humidity outside the ship should be tested as a reference, but the TEMP and RH is very different every day, and the season of shipment is unstable, what does this means in terms of shipping validation?
3) For mapping stability chambers, if we want to study the effects of an open door and power failure, how do we decide the length of the study? For example, we have used study lengths of 15 minutes, but I want to be able to justify that duration to an inspector. Can you describe how to rationalize study length?
I have essentially the same questions for our incubator applications… MKT? Study length?
I greatly appreciate any advice you can provide – and thanks in advance! /Z
First off, thanks for reaching out! I will do my best to answer your questions. First, however, I would like to clarify your questions to make sure that I understand what you are asking. For questions 1 and 2, it sounds like you want to map a shipping container for a sea shipment of temperature-sensitive pharmaceutical products. Also, it sounds like the container is smaller than 20m3. Most shipping containers are quite a bit larger than that.
However, in general for Questions 1 and 2: Mapping a shipping container at sea is VERY different than mapping an incubator, stability chamber, warehouse etc. One of the primary differences is that the shipping container cannot be controlled while it is at sea, so it is considered to be temperature profiling, rather than mapping. Profiling such a container will really only help you if it is refrigerated or air conditioned. And even then, the profiling really just identifies places in the unit that are unsuitable for storage. I think, in your case, you would be better off finding ways to monitor the packages, with temperature loggers, rather than mapping the shipping container.
For your question on study duration: There is no duration requirement for these types of tests. I will guess that your company uses 15 minutes because it sounds like a good number. I would use a different approach: test the chamber to see how long the temperatures stay in specification, and use that number when doing future deviation resolution. Now, I confess that I personally prefer NOT to do these types of tests, as I believe they provide little useful information. In my experience, you are better off with a good monitoring system. A monitoring system with door contact alarms will let you know that the door is open, or what temperature is inside the chamber when the power has failed. Also, since we are talking about stability chambers, these are units that should not be opened frequently, so these tests are not really applicable.
Regarding Mean Kinetic Temperature: You should not be using MKT calculations in a stability chamber. Stability chambers are supposed to be… well, stable. We use MKT for instable environments. If you need to calculate MKT then your stability chambers aren't stable. So, you've got some bigger problems. Validation in incubators, refrigerators, warehouses, freezers is very much the same. That said, incubators are different in one significant way; they aren't storing product. Incubators grow cultures and cultures are strongly affected by variations in temperature and humidity. Calculating MKT would probably just be indicative of a larger problem. MKT was first developed and applied to ambient storage in warehouses. I would be very cautious trying to apply this calculation to incubators and stability chambers, as neither of these are used for finished and packaged products.
I hope this helps! Please feel free to email me if you want to discuss further!