Twenty Questions to Ask Your Cryogenic Storage Room Before an Inspector or a Failure Does

A cryogenic storage room can go years without a problem and still not be ready for one. A self-audit is the cheapest way to find out the difference. It takes one person half a day, needs no new equipment for most of its questions, and should be scored honestly as pass, partial or fail.

The vessels and the fill log

Shortening fill intervals are the earliest signature of vacuum decay, and they are only visible if someone has plotted them. Check that every vessel has a written fill log with dates and volumes, a legible asset label, a known age and a known vacuum warranty status. Look for frost, condensation or a damp ring on the vessel body, which is a different finding from neck frost.

Monitoring that has actually been tested

An independent alarm should alert a named person's phone out of hours. Test it end to end by cooling or disconnecting the probe, not by pressing a test button. Confirm the oxygen depletion monitor is in calibration, mounted at the right height and alarmed somewhere a person will hear it. Most storage disasters begin on a Friday evening, so ask who checks these systems before a bank holiday weekend.

An inventory you can prove

You should be able to list what is stored in every canister of every vessel within one hour, and a physical spot check of two random goblets should match the record. Storage consents and storage term limits need a forward alert before expiry, and any sample belonging to someone the organisation can no longer contact needs a decision.

A plan that survives a staff change

Standing transfer capacity on site, whether an empty vessel or a dry shipper that could be charged today, is what turns a plan into something usable. The transfer procedure should name who moves what and in what order, more than one person should be able to run it, and it should have been walked through physically since the last staff change.

People and paper

Everyone who opens a vessel needs documented training in the last two years, including the frost line rule for retrievals. Service visits should be up to date for every vessel and controlled-rate freezer, with actions closed, and consumables should trace back to batch certificates. Then ask the question that catches the most programmes: if your most experienced person left tomorrow, would any part of this system leave with them?

Scoring

Zero to two fails, fix them this month. Three to six, the programme depends on individual diligence rather than system design, so deal with monitoring and the emergency plan first. Seven or more, and samples are being protected by luck.

The full list of twenty questions is in our article, The Annual Cryo Storage Self-Audit.