How Long Does Dry Ice Last?

Plan on using 5 to 10 pounds of dry ice for every 24-hour period depending upon the thickness of the insulated shipping container. This will keep everything frozen in a container u to 15 quarts. For larger containers and greater shipping times multiply dry ice quantities by this rate. The best shipping container is a three-inch thick urethane insulated box tested to loose only 5 pounds for a 10-quart storage area every 24-hours. When packaging items in the container fill the empty space with wadded newspaper of a paper bag. Any "dead-air-space" will cause the Dry Ice to sublimate faster. 

Dry Ice sublimation (changing from a solid to a gas) will vary depending on the temperature, air pressure and thickness of insulation. The more Dry Ice you have stored in the container, the longer it will last. Dry Ice, at -109.3⁰F or -78.5⁰C, will freeze and keep frozen everything in its container until it is completely sublimated. These frozen items will still take some extra time to thaw because they will have been so cold.