Coolant Pack
A coolant pack is a cooling element filled with a thermal storage medium. After preconditioning, it absorbs heat and thereby supports temperature control in an insulated shipper. Depending on its format and design, it is intended for single or repeated use.
How does a coolant pack work?
- Water-based packs buffer heat as they warm, and particularly as the ice melts at around 0 °C. Chilled, unfrozen water packs can also be part of a packout.
- Specially formulated PCMs use a phase change range selected for the application. They absorb heat when melting and release heat when solidifying. In physical terms, water is also a PCM.
- The format alone does not identify the medium inside: gel packs, foam bricks and rigid-shell packs can contain different fillings, depending on the version.
Is a frozen pack suitable for +2 to +8 °C?
This cannot be determined from the pack alone. Elements that are too cold, or direct contact, can overcool sensitive products. The decisive factor is the tested combination of shipper, pack type, quantity, preconditioning, arrangement and load.
The melting point is therefore neither the guaranteed product temperature nor an indication of shipping duration. Coolant packs should be prepared and used in accordance with the associated packing instructions.
Related terms: Cooling Element · PCM
Technical references:
WHO: Passive thermal packaging and packing configuration, section 6.9