BREATHABILITY AND RECOVERY TIME
Certain products need breathable packaging but they also have to be kept within a narrow temperature range. This means they require a breathable thermal cover during transit.
But what are the benefits and drawbacks of a breathable thermal cover?
Breathable covers, by definition, allow some amount of airflow. Because the outside air is at ambient temperature, it can accelerate temperature exchange between the payload and its environment. This can be a good or a bad thing.
If an excursion happens during shipping, the time the temperature takes to return to the label claim is called the recovery time. Breathable covers can help reduce this recovery time when the payload is in a controlled environment. However, when in an uncontrolled environment, it also speeds up temperature exchange.
For example, say a payload’s label claim is between 15–25ºC, and it is conditioned at 20ºC. It is then released from the warehouse to be loaded onto a plane. The extreme temperatures on the tarmac slowly heat it up to 27ºC, but once it is in the plane it can start to recover. Since a breathable cover is used in this case, the recovery time will be shorter. In just 10 minutes, the payload temperature may already be at an acceptable 25ºC. However, if a non-breathable cover was used, it is possible that the temperature would not have exceeded 25ºC to begin with. This is because the hot ambient air can’t enter the non-breathable cover.
What does this all mean? Should you never use a breathable cover?
No. Some products require breathable covers and, in such cases, they should definitely be used. However, for products that don’t need breathability, the benefit of faster recovery time is less desirable than avoiding the excursion in the first place.
If you need help choosing the right thermal cover or you would like more information, get in touch today.