A cryogenic tank is an insulated pressure vessel or open-necked dewar engineered to store or transport cryogenic liquids at temperatures below minus 150 degrees Celsius. In an IVF laboratory context, the term refers primarily to liquid nitrogen storage dewars used to preserve embryos, oocytes, and sperm at minus 196 degrees Celsius. These vessels use vacuum-jacketed double-wall construction and multilayer superinsulation to minimise heat ingress and liquid nitrogen evaporation, maintaining stable ultra-low temperatures without electrical power.
Cryogenic facilities in a UK licensed fertility clinic must meet the requirements of the Human Fertilisation and Embryology Authority (HFEA) Code of Practice, which sets standards for storage vessel monitoring, traceability, temperature logging, and emergency procedures. The HFEA requires that licensed storage facilities hold a valid storage licence, maintain continuous temperature monitoring with alarm systems, document all sample movements, and have written contingency plans for equipment failure or liquid nitrogen supply disruption.
In practical terms, a compliant cryogenic facility requires adequate ventilation to manage oxygen depletion risk from liquid nitrogen off-gassing, continuous oxygen monitoring with audible alarms set to trigger at 19.5 percent oxygen concentration in line with Health and Safety Executive (HSE) guidance, restricted access controls, and a documented vessel maintenance and servicing schedule. The British Compressed Gases Association (BCGA) Codes of Practice CP30 and CP36 provide detailed guidance on safe handling of cryogenic liquids in laboratory and clinical settings. Cryolab supplies UKCA and CE marked cryogenic tanks to IVF clinics and research institutions. The full storage vessel range is available at cryolab.co.uk/storage-vessels/.
