Cord blood cannot be stored in a regular freezer, it needs to be kept extremely cold, -130 degrees Celsius. Because of this, it is stored in a nitrogen freezer. There are 2 types of nitrogen freezers, liquid and vapor. A liquid nitrogen freezer submerges the samples directly into the nitrogen. A vapor nitrogen freezer uses nitrogen to chill the air within the freezer.
When cord blood storage first began, all cord blood was stored in liquid nitrogen freezers. While it maintained temperature, specialists were concerned with the possibility of germs or bacteria being able to “swim” through the nitrogen from one sample to another.
Scientists began to develop other techniques to store cord blood. They discovered that cord blood could be stored in vapor nitrogen, but, in the beginning, there were some issues with maintaining temperature. Technology has developed rapidly since that time and now most cord blood is stored in vapor nitrogen with no danger of temperature fluctuations. This eliminates any possibility of contamination while maintaining a constant temperature.
In addition, most laboratories, like M.A.Z.E. Cord Blood monitor the tanks’ temperatures electronically and have multiple back-up alarm systems to ensure the temperature is not compromised in any way.