A dry shipper is a specialised cryogenic transport vessel that maintains ultra-low temperatures using liquid nitrogen absorbed into a porous material lining the interior of the vessel rather than carrying free liquid nitrogen. When the absorbent material is saturated with liquid nitrogen, the vessel generates a stable vapour phase environment typically between minus 150 and minus 190 degrees Celsius inside the sample chamber, sufficient to preserve cryopreserved biological material during transport without the risk of liquid nitrogen spillage.
The distinction between a dry shipper and a conventional cryogenic container for biological sample transport is critical for both safety and regulatory compliance. International air transport regulations permit dry shippers charged with liquid nitrogen to be transported by air as non-restricted articles when properly prepared and certified, whereas vessels containing free liquid nitrogen are classified as dangerous goods requiring hazardous materials documentation and specific packaging. This makes dry shippers the standard choice for inter-clinic embryo transfers, international sperm bank shipments, and research specimen logistics.
When selecting a biological sample transport vessel, the key parameters to evaluate are hold time at the required temperature with the vessel fully charged and loaded, available sample capacity in terms of canister positions and compatible cryovial formats, the charging protocol and time required to prepare the vessel before dispatch, physical dimensions and weight relative to transport logistics, and documentation of temperature performance suitable for inclusion in chain-of-custody records. Cryolab supplies the CryoStork range of dry shippers, which are used by IVF clinics and sperm banks across the UK and internationally. Full specifications and hold time data are available at cryolab.co.uk.
