How Long Dry Ice Lasts Outside The Freezer And How To Prolong Its Lifespan

Dry ice is the solid form of carbon dioxide and the perfect trick to keeping ice cream frozen in your cooler thanks to it being colder than regular ice at around -109 degrees Fahrenheit. However, dry ice doesn't last forever. If you took the time to find out where to buy dry ice for an event, it would be a bummer if it were to sublimate before the big day comes around. 

The lifespan of dry ice depends on factors like size and storage. If you have a five-pound block of dry ice in a cooler, it should last 18 to 24 hours, depending on the quality of the cooler and how often it's opened and shut. If outside, that same block of dry ice will last between three and five hours. If you're keeping the block in a liquid (for creating a cool fog effect, for example), expect it to last only 45 minutes.

Dry ice is lighter than regular ice and comes with the added benefit of less mess since it evaporates rather than melting into a puddle. There's some guesswork involved with dry ice, though, like making sure you have the proper amount. When buying dry ice, it's important to plan for its evaporation ahead of time. If you need a 5-pound block, it may be best to purchase a 10- to 15-pound block if your event is still a day out. Dry ice — like regular ice — is typically something you'd want to buy as close to your time of need as you can.

If you need dry ice to last longer, there are a few ways to extend its life. One way is to keep it in block form. If you break it down into an ice-cube-esque state, it will evaporate at a faster rate. Another is to make sure you're using a high-quality, insulated cooler. Even better if you can make the inside of the cooler cold before putting the dry ice inside, just stack some ice or frozen goods in it for a few minutes before replacing them with the dry ice. Make sure to keep it away from liquid (at least, until you need to use it).

When you've mastered the art of dry ice longevity, sharpen your dry ice safety skills, too. To safely use dry ice in your coolers this summer, there are strict rules to follow. For starters, don't ever touch dry ice with your bare hands or you'll run the risk of frost bite. Instead, wear gloves or move it with tongs. Make sure to use dry ice in an open, well-ventilated area or store it in a ventilated cooler. As dry ice evaporates, it emits carbon dioxide gas, which can be dangerous if you allow it to build up pressure.