Cold Shock – Damage from Excessive Cooling and Freezing
In the pharmaceutical cold chain, cold shock refers to excessive cooling that may damage a product. Freeze-sensitive medicines can suffer permanent damage, particularly through freezing. The product-specific lower temperature limit is decisive; for a specified range of +2 to +8 °C, a temperature excursion already begins below +2 °C.
What causes cold shock?
- Coolant packs used at too low a temperature can remove too much heat from the product, especially at the start of transport. This can also happen in summer.
- Direct contact with frozen packs can cause lower local temperatures than those in the centre of the payload space.
- Cold ambient conditions can also take the product below its permitted temperature if the packaging system is not adequately designed for them.
What helps prevent it?
Coolant packs, preconditioning and their arrangement must match the tested packout. Suitable PCMs, defined separation distances or internal insulation can reduce the risk. Their effectiveness must be tested in the complete system under relevant summer and winter conditions.
A temperature excursion alone does not establish that freezing damage has occurred. Whether the goods may still be used must be assessed using product data and the defined quality procedure.
Related terms: Temperature Excursion · Preconditioning