Hold time is the specification that defines how long a dry shipper maintains cryogenic temperatures after charging, without any additional liquid nitrogen input. It is the most clinically important performance figure for any dry shipper used in biological sample transport, and it varies between CryoStork models based on internal capacity and the efficiency of the vacuum insulation.
Hold time across the CryoStork range
The hold time figures for each CryoStork model are detailed in the product data sheets available from Cryolab. Cryolab describes the CryoStork range as offering market-leading hold times across all five models. The V10, with its 10-litre capacity, provides the longest hold time in the range and the largest safety margin for extended or complex transfer routes. For domestic UK transfers, the hold time of even the compact V2 significantly exceeds the duration of any realistic road or air journey within the UK.
Matching hold time to your transfer route
For international transfers involving long-haul flights, potential transit delays or customs hold periods, hold time becomes a primary selection criterion and a larger model with a longer hold time is appropriate.
Hold time should always be evaluated against the worst-case scenario for a given transfer route, not the typical scenario. A transfer that normally takes eight hours could take 24 hours if a flight is cancelled or a customs clearance is delayed. The vessel selected must be able to sustain that delay without temperature excursion.
What affects real-world hold time
Real-world hold time can be affected by the number of times the vessel is accessed during transit, ambient temperature conditions, and the condition of the vacuum insulation. Vessels approaching the end of their working life or that have been subjected to impact damage may achieve shorter hold times than their rated specification. Pre-use verification of hold time before critical transfers is good practice. For hold time data specific to each CryoStork model, contact Cryolab to request the product data sheet or view the full range here.
