Qualifying a Packaging System Under Most Challenging Conditions

By Frank Butch, Engineering Manager, Sonoco ThermoSafe

Temperature Assurance Packaging is generally qualified for minimum and maximum product loads of a specific product or product range. These shipping systems are normally qualified to a standard shipping lane or distribution channel. Once they have been qualified there is little flexibility to alter the bracketed product loads without updating documentation and repeating operational and performance qualifications. The time and cost associated with such documentation updates further limits shipping systems flexibility.

To address this, “pre-qualified” shippers are available throughout the industry. But, these shippers may not have been tested against a representative product volume. A large payload is slower to change temperature when exposed to a given ambient temperature profile and conversely, a small payload will change temperature more rapidly. In addition, the ambient temperature profiles tested may not be representative of the actual shipping lane. A deviation from the representative shipping lane may result in a shipping system which is over or under designed resulting in higher costs, excess components, or poor performance.

The location of the temperature probes used during testing is defined by the manufacturer of the shipping system but there is a temperature gradient within the shippers. These disparities can add up to enough of a difference to where the “prequalified” shipper has not been challenged against the extreme temperatures that may be experienced outside of the standard shipping lane.