Cryogenic storage typically involves cooling materials to temperatures below -150°C (-238°F) using liquid nitrogen or other cooling agents. This extreme cold halts biological activity and biochemical reactions, effectively "freezing" the specimen in time. The main methods include:
1. Liquid Nitrogen Tanks: These are commonly used for storing biological samples at temperatures around -196°C (-320°F). 2. Ultra-Low Temperature Freezers: These freezers can reach temperatures as low as -86°C (-123°F), suitable for many epidemiological samples but not as cold as liquid nitrogen tanks.
