How to test an Isothermic Bag
Uwe Diegel, founder of MedActiv, talks about testing the MedActiv isothermal bags
I am often asked how the MedActiv bags are tested and how we can guarantee that they will keep the medication inside at the right temperature for the right amount of time.
As we are in a continuous quest for zero-defects, we go through great lengths to ensure that our bags deliver a perfect performance every time.
There are a number of elements to consider when we test bags, which are ambient temperature, what the medication is, and the static temperature of the actual medication. What interests us is the temperature of the medication itself (not the air around it).
1) Syringes, flacons and pre-filled pens filled with water
2) Temperature controllers (I use a MadgeTech Thermocouple Data Logger, with 8 different temperature probes)
3) A temperature-controlled black box that will keep the tested bag at a steady temperature.
When we do testing, we try and reproduce as much as possible the normal conditions of utilization. So we first fill syringes, pens, and flacons with water and place them in a household fridge so that they are between 2 and 8°C.
We then prepare the bag to be tested by placing the gel packs in a freezer at -18°C for a minimum of 14 hours. -18°C is the temperature of a standard household freezer.
We insert the MadgeTech temperature probes inside the syringes, pens and flacons filled with water so that they are inside the liquid and measure the temperature of the liquid itself. The temperature probes are linked to the MadgeTech temperature controller, which is linked to a computer that records the temperature every minute.
So this is the setup:
The flacons/syringes/pens are then placed inside the MedActiv bag being tested, together with the well-frozen gel packs in the correct position.
The entire MedActiv bag being tested is then placed in a controlled temperature environment (black box) which is maintained at a steady temperature of 24,2°C.
The computer will then record the temperature every minute over 12, 24, or 36 hours, depending on the bag being tested.
24,2°C is considered internationally to be an average ambient temperature, and is indeed the temperature that is kept inside of airplanes. As most people use MedActiv bags to travel in airplanes, it is the reference temperature used to test isothermal bags.
What if I use my MedActiv bag at a higher temperature?
If you use a MedActiv iCool Prestige bag, which is tested to keep your medication between 2 and 8°C for 24 hours, at an ambient temperature of 30°C, it will not last nearly as long as 24 hours. It might only last 12 or 13 hours.
Every effort is made at MedActiv to make bags that give a perfect performance, but the bag’s performances are dictated by the intrinsic limitations of the environment that they are used in.