The separator between a product and an ice pack is more than filler: it manages direct cold contact, abrasion, condensation and load movement together. If it disturbs closure or airflow, it changes the pack-out instead of protecting the product. The product's outer carton, a washable divider or a suitable disposable board may be a candidate.
Define the load and the cold source first
Product packaging, freeze sensitivity, starting temperature, total duration and pack model are the inputs. Keep preparation apart from packing: in GEBHARDT's plate document the freezing rack leaves an air gap between plates so cold air can circulate. That does not mean the same gap belongs in every shipping box.
The material must not crack at low temperature, disintegrate when wet, shed fibres or filler, or interfere with the lid. A food-suitable outer shell on an ice pack does not make leaked filling safe to touch the product; the filling and the packaging incident are assessed separately, since ice-pack contents vary (National Capital Poison Center).
A thin film, paper or generic wrap may limit contact and abrasion; how far it changes heat transfer is shown by the pack-out and measurements. More thickness is not automatically an improvement: usable volume, airflow, lid closure and product damage are reviewed together.
| Separator candidate | What to inspect in a trial | Reason to change it |
|---|---|---|
| Product carton or cardboard board | Shape when damp, compression, pack movement | Softening, breakdown or loss of the gap |
| Reusable divider | Integrity at low temperature, cleanability | Cracks, an uncleanable surface or a blocked lid |
| Suitable insulating board | Product temperature, occupied volume, staying in place | Temperature deviation or slipping that exposes goods |
| Thin film / wrap | Permitted contact and packaging function | Being relied on alone for freeze protection |
Define it in the pack-out
WHO's supplement on shipping containers defines a pack-out as one package of product, temperature-stabilizing medium, partitions, secondary packaging, data logger and dunnage. That is a qualification principle for pharmaceutical containers and not a legal rule for commercial food boxes, but it is a good reason to treat the separator as a defined part of the package (WHO).
Record separator type, orientation and count with a photograph; similar cardboard found in the warehouse is not an approved substitute. If you change the separator, pack orientation, pack quantity, product packaging or spacing in an approved arrangement, record it as a separate configuration and do not carry the acceptance result over to the same route and load. Check clearance and closure first, then measure with the real product and inspect contact and abrasion. If a deviation occurs, affected product is set apart and evaluated; restoring the temperature alone does not release it (FAO HACCP Step 9, Step 10).
See ice-pack placement in an EPS box for the layout and leaking-pack checks for a damaged pack.
