The “cold chain” is the system in which products and supplies that must be maintained within a prescribed temperature range from origin to destination are distributed. In order to preserve their integrity, it is crucial for products that are extremely temperature-sensitive — such as vaccines and pharmaceuticals — to be kept within certain temperature boundaries during storage and transit.
The lives and health of people all over the world depend on the safe delivery of medicines, blood products and biomedical materials. To that end, special shipping containers have been developed within the cold chain industry. These containers are well-insulated and built to hold temperatures for relatively lengthy periods of time under conditions often less than favorable.
An Intensive Qualification Process
With the life-and-death implications attached to the temperature stability these containers must provide while in transit, they must undergo rigorous testing before being qualified to enter the field. This validation process is meticulously regulated and overseen by agencies such as the Parenteral Drug Administration (PDA) and the International Safe Transit Association (ISTA).
Testing takes place in industry-approved laboratories where containers are exposed to extreme environmental conditions and subjected to vibration, compression and “drop” scenarios among other physical hazards. Temperature monitoring equipment must be sound and reliable as it measures temperature hold times during the qualification process.
Thermocouple temperature probes and thermistor temperature sensors are used in conjunction with temperature indicator and data logging equipment to measure and document internal container temperatures during testing. Temperature calibrators are used to adjust the monitoring equipment to ensure accuracy. If there are any inconsistencies or discrepancies detected during qualification procedures, the container in question will not be validated.
Precision in temperature measuring and monitoring is the most critical aspect within cold chain container testing. Not only is the efficacy of cold chain packaging relied upon for the successful delivery of life-saving products, but the potential financial loss is sizeable when these products are spoiled or rendered ineffective upon arrival.