The point when dry ice runs out and the product's temperature change are not the same event. Insulation and load thermal properties can affect the result; time within an acceptance range cannot be known without measuring the actual load and route.
In a test, weigh or otherwise record dry-ice mass at the start and end. Use a logger to measure product temperature at a defined point; include packaging, starting temperature, load quantity and ambient conditions on the same record.
On a route representing hot-season or delay conditions, align the product-temperature curve with the dry-ice depletion record by time. A change in load, fill, packaging or exposure changes the test conditions. An observation from one run does not automatically authorise another shipment.
Compare readings with product acceptance requirements. If a limit is exceeded, records are missing or sensor position is uncertain, the dispatch and quality owners should follow procedure. Do not use the observed post-dry-ice duration as a reserve or safety margin in route planning.
