Volume matters enormously in a clinic processing dozens of patient samples per week. A large liquid nitrogen dewar allows segregated storage by patient, date, and cycle without the constant cycle of filling, emptying, and re-cataloguing that plagues smaller vessels. Cryolab larger vessels include canister withdrawal systems and lockable tops, giving clinic staff fast, organised access without disturbing adjacent samples. A well-chosen large dewar also reduces staff handling time, which is a direct infection control benefit.